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^o. 84

BIBLIOGRAPHY ON IONOSPHERIC

PROPAGATION OF RADIO WAVES

(1923 - I960)

BY

WILHELM NUPEN

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

Functions and Activities

The functions of the National Bureau of Standards are set forth in the Act of Congress, March

3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and

maintenance of the national standards of measurement and the provision of means and methods for

making measurements consistent with these standards; the determination of physical constants and

properties of materials; the development of methods and instruments for testing materials, devices.

and structures; advisory services to government agencies on scientific and technical problems; in- vention and development of devices to serve special needs of the Government; and the development

of standard practices, codes, and specifications. The work includes basic and applied research. development, engineering, instrumentation, testing, evaluation, calibration services, and various

consultation and information services. Research projects are also performed for other government

agencies when the work relates to and supplements the basic program of the Bureau or when the

Bureau's unique competence is required. The scope of activities is suggested by the listing of

divisions and sections on the inside of the back cover.

Publications

The results of the Bureau's work take the form of either actual equipment and devices or published papers. These papers appear either in the Bureau's own series of publications or in the journals

of professional and scientific societies. The Bureau itself publishes three periodicals available from

the Government Printing Office: The Journal of Research, published in four separate sections,

presents complete scientific and technical papers; the Technical News Bulletin presents summary

and preliminary reports on work in progress; and Basic Radio Propagation Predictions provides

data for determining the best frequencies to use for radio communications throughout the world.

There are also five series of nonperiodical publications: Monographs, Applied Mathematics Series,

Handbooks, Miscellaneous Publications, and Technical Notes. Information on the Bureau's publications can be found in NBS Circular 460, Publications of the

National Bureau of Standards ($1.25) and its Supplement ($1.50), available from the Superintendent

of Documents, Government Printing Office, Washington 25, D.C.
NATIONAL BUREAU OF STANDARDS

technical ^Ttote

No. 84

October I960

BIBLIOGRAPHY ON IONOSPHERIC

PROPAGATION OF RADIO WAVES

by

Wilhelm Nupen

NBS Technical Notes are designed to supplement the Bureau's regular publications program. They provide a means for making available scientific data that are of transient or limited interest. Technical Notes may be

listed or referred to in the open literature. They are for sale by the Office of Technical Services, U. S. Department of Commerce, Washington 25, D. C.

DISTRIBUTED BY

UNITED STATES DEPARTMENT OF COMMERCE

OFFICE OF TECHNICAL SERVICES

WASHINGTON 25, D. C.

Price $ 7 . 00

CONTENTS

INTRODUCTION Page i

SUBJECT OUTLINE.

GEOGRAPHIC OUTLINE xxxi

BIBLIOGRAPHY ON IONOSPHERIC PROPAGATION

AUTHOR INDEX 414

SUBJECT INDEX 427

BIBLIOGRAPHY ON IONOSPHERIC PROPAGATION OF

RADIO WAVES (1923-1960)

INTRODUCTION

This bibliography comprises a non-exhaustive compilation of

over 1400 references to the world's literature on the ionosphere with

special emphasis on its effect on reflection, refraction or propagation

of electromagnetic waves. The frequencies involved are usually in

the low frequency or long wave bands in contrast to those(UHF, VHF

and SHF) involved in tropospheric propagation investigations although

the pulsed technique at vertical or slant incidence makes use of a wide

range of frequencies.

Several distinct fields of ionospheric propagation have been

purposely omitted in order to keep the volume of material down to

manageable proportions. There are: Meteor or meteor trail propagation

Radio reflection from auroras Radioastronomy

These, and related aspects, will be the subjects for a smaller

supplementary volume; and the accumulated literature on Tropospheric

Propagation for still another volume, also of somewhat smaller dimensions.

Although material from every country, where ionospheric investigations are being carried on, is included herein, the user will no

doubt be aware that more material from U.S. and Japanese, and corres- pondingly less material from French, German and Russian sources, has

been included than would be the case if a more exhaustive coverage

were possible. Eventually, the literature of these countries (and of

the U.S.A. ), which has been overlooked in this bibliography, will be

included in one or other supplement to this volume.
ii

Every effort has been made to avoid errors in citations and although scores of errors have been discovered in proof and corrected,

many others have no doubt gone undetected. If anyone should find a serious error, such as in the spelling of an author's name, or in the

date of publication, we should be pleased to have such called to our

attention. Similarly, notice of any serious omissions should be communicated, with or without an abstract, so that supplements will be

as exhaustive as possible.

The material is arranged alphabetically by the first author's

name, and chronologically under each author. An author index is provided for the purpose of identifying works of added (i. e. , second or

third) authors where teams have cooperated in writing an article. A

subject and place outline, and subject index are also provided in

order to give the reader an idea of the scope of the subject material

involved. Obviously, with such a large total number of items on a fairly

narrow range of subject matter, there will be too large a number of re- ferences on some subjects no matter how noble an effort is made to subdivide the material under each heading.

We y, ish to express great appreciation for the work performed

by Mr. Otto Taborsky in preparing the systematic geographical outline

which follows the subject outline, and to Mrs. Dorothy Gropp for

checking the accuracy of serial citations, and to Mrs. Doris Nickey

for the months of work she has performed in typing and correcting copy

for this voluminous work.

Finally, we wish to express our appreciation to the National

Bureau of Standards Boulder Laboratories for support of this compilation,

and especially to Mr. Bradford R. Bean, of that Laboratory, for his

patient guidance in helping to determine the general scope and arrangement of material herein, and for many of the entries submitted by his

laboratory; and to the Air Force Cambridge Research Center, under

whose sponsorship much of the original work which went into the
Ill

product was performed. These items are identified by the initials of

the abstractors as indicated below.

Considerable use was made of the excellent bibliographies

prepared in 1947 and 1955 by L. A. Manning (items A-799 and 803),

in checking and searching for missing references. Any of the abstracts taken from this source are indicated by the initials L. A.M.

Malcolm Rigby, editor

Meteorological and Geoastrophysical Abstracts

Box 1736, Washington 13, D. C.
iv

Note:

Abstractors/Ionospheric Propagation Bibliography

MGAStaff members:

Others

C. E. P. B C. E. P. Brooks

I. L. D. Isadore L. Dordick

M. L. R Mary L. Rice

M. R Malcolm Rigby

G. T Geza Thuronyi

A. A Andrew Assur

A.M. P Alexis M. Poushkin

G. J. E Gwynn J. Evans

I. S Ismael Saad

W. N Wilhelm Nupen

A. V Andre Vandenplas

N. N Nndem E. U. Nndem

N. A. Z Nicholas A. Zikeev

R. P Robert L. Panara

L.A.M. = L. A. Manning

Physics Abstracts

Science Abstracts of China, Earth Sciences

Institute of Radio Engineers, Proceedings

Library Symbols:

DBS U. S. National Bureau of Standards,

Washington, D. C.

DGS U. S. Geological Survey, Washington, D. C.

DLC Library of Congress, Washington,

D.C.

DWB U. S. Weather Bureau, Suitland,

Maryland

DN-HO U. S. Navy Hydrographic Office,

Suitland, Maryland
SUBJECT OUTLINE

I. GENERAL WORKS

1. Textbooks, monographs, manuals. A-164, 177, 188, 189, 190,

299, 300, 356, 378, 385, 479, 489, 503, 542, 628, 655,

658, 693, 742, 756, 764, 773, 820, 907, 946, 948, 952,

1009, 1013, 1018, 1026, 1157, 1218, 1235, 1250, 1252,

1359, 1360

2. General Reviews and Surveys. A-6, 10, 24, 26, 34, 84, 136,

146, 159, 175, 184, 221, 252, 313, 320, 354, 391, 400,

401, 408, 429, 437, 448, 457, 481, 487, 503, 569, 572,

590, 644, 657, 669, 707, 709, 728, 856, 760, 763, 764,

769, 771, 795, 804, 806, 835, 839, 845, 848, 862, 863,

882, 888, 890, 894, 961, 988, 1001, 1047, 1054, 1123,

1157, 1164, 1200, 1201, 1211, 1233, 1235, 1236, 1249,

1254, 1276, 1309, 1310, 1339, 1358, 1384, 1402

3. Data publications. A-80, 87, 90, 123, 156, 174, 176, 179,

185, 223, 226, 229, 231, 272, 275, 277, 285, 301, 322-

325, 330, 376, 403, 426, 436, 448, 451, 459, 467, 480,

488, 507, 527, 567, 578, 581, 583, 597, 599, 617, 618,

621, 627, 629, 633-636, 638, 644, 645, 653, 655, 663,

666, 685, 692, 706, 713, 716, 738, 742, 760, 768r771,

775, 795, 799, 809, 818, 826, 827, 833, 834, 843, 844,

857, 858, 860, 864, 872, 873, 880, 891, 896, 900, 914,

927, 935, 948, 952, 961, 983, 1030, 1035-1037, 1040,

1081, 1088, 1089, 1101-1103, 1106-1108, 1112, 1122,

1136, 1165, 1169, 1208, 1215, 1229, 1233, 1237-1239,

1245, 1247, 1249, 1250, 1271, 1276, 1284, 1293, 1294,

1322, 1350, 1359, 1360, 1364, 1376, 1384, 1386, 1403

4. Ph. D. Theses. A-659, 885

M. S. Theses. A-302

5. Maps and nomograms. A-164, 204, 277, 330, 360, 455, 669,

823, 876, 901, 919, 933, 948, 1080, 1234, 1322

6. Bibliographies. A-7, 10, 22, 24, 90, 136, 174, 246, 417, 424,

479, 481, 608, 610, 635, 644, 653, 659, 747, 799, 803,

839, 848, 851, 907, 934, 935, 952, 1013, 1026, 1157,

1192, 1211, 1233, 1283, 1309, 1310, 1384, 1386

7. History. A-24, 26, 175, 252, 429, 487, 488, 590, 596, 676,

724,736, 917, 958, 1161, 1231, 1276, 1293
VI

8. Conferences, Symposia. A-3, 142, 143, 171, 294, 313, 452,

457, 497, 507, 550, 600-610, 628, 636, 647, 648, 742,

760, 804, 823, 849, 850, 852, 882, 892, 896, 941, 952,

976, 1002, 1003, 1037, 1040, 1079, 1136, 1158, 1163,

1195, 1202, 1218, 1271, 1306, 1307, 1333, 1389, 1391,

1393, 1396, 1402

9. Research programs. A-1121, 1166, 1169, 1176, 1390, 1399,

1401

10. Nomenclature. A-96, 200, 487, 900, 1080, 1139

II. THEORIES

Appleton's attenuation equivalence theorem. A-74, 781

Argence's theory. A-86

Atmospheric tidal theory. A-1340

Bailey's wave interaction theory. A-475, 562, 564, 596r598,

705, 866, 1257

Barkhausen and Eckersley's theory. A-726

Booker, Ratcliffe and Skinn's diffraction theory. A-255

Bradbury's hypothesis. A-815

Breit and Tuve's theorem. A-532, 575

Budden's theory. A-973

Chapman's theory. A-76, 77, 79, 192, 237, 354, 680, 893

Chordal-Hop theory. A-16

Communication theory. A-628

Dieminger-M oiler's theory. A-371

Directional fluctuations due to ionospheric irregularities. A-243

Dissociation and recombination. A-889

Doppler shift theory. A-383

Dynamo theory. A-107, 108, 288, 895, 1140

Echo delay theory. A-937

Electron-ion cloud radio reflections. A-402

Electron theory. A-773

Es theory. A-1209

Fading theory. A-114, 121, 1000

F-region theory. A-815

Gradient mixing theory. A-1335

Grenet's theory. A-493

Heaviside's propagation theory. A-539

Helliwell's theory. A-1394

Ionospheric diffusion of electrical waves. A-611

Ionospheric drift theory. A-1397

Ionospheric duct theory. A-1394

Ionospheric irregularities. A-271

Layer formation below E. A-237, 238

LF reflection theory. A-972, 973

LF wave theory. A-289, 409, 410, 886, 904r 906
Vll

Lorentz's dispersion theory. A-685f 687

Magnetic coupling theory. A-574

Magneto-ionic theories. A-5, 41, 92, 100, 218, 452, 690,

781, 869, 944, 1013, 1060

Martin's theory. A-596, 597, 598

Martyn's absorption theorem. A-19, 63, 532, 1024

Motion of weak irregularities. A-308

New geometrical properties. A-1224

New Ionization mechanism. A-599

Quantum theory. A-542

Quasi-longitudinal theory. A-640

Radio transmission theory. A-164

Radio wave scatter theory. A-908

Ray theory. A-410

Reflection theory. A-877, 1070

Scott's collision freguency. A-393

Sellmeyer's dispersion theory. A-685, 687

Short wave communication. A-184

Slow tail theory. A-557

Sommerfield's theory. A-883

Spherical wave theorem. A-430

Statistical fading theory. A-123

Store -Eckersley's theory. A-322, 380, 553

Triple split theory. A-1032, 1060, 1062

Turbulence theories. A-213, 1068, 1165, 1177, 1336, 1338

Van der Pol's theory. A-248

VLF west attenuation east. A-325

Wave guide mode. A-132, 1273, 1274, 1280

Wave interaction. A-327, 412

Wave theory. A-467

Whistler propagation theory. A-571

Survey of theories. A-813, 1068

III. FORMULAS

Al'pert's. A-27

Appleton-Hartrees'. A-84, 100, 162, 413, 884, 918, 1107

Argence's. A-84

Atmospheric electric equilibrium. A-612

Boltzmann's. A-631

Bremmer's vertical incidence solution. A-497

Chappel's ion movement velocity. A-296

Conductivity. A-107

Continuity, Electron density. A-288, 387

Correlation method. A-501

E layer drift. A-79

E layer. Steady reflection part. A-120

Fading pattern. A-11
Vlll

FORMULAS - concl'd.

Flat ionosphere/curved earth. A-57

Gauss -Christoffel quadrature eqs. A-689

Kelso's method. A-689

Mawell's. A-632

Poynter and MacDonald's velocity method. A-569

Radio transmission. A-94, 218

Radio wave absorption. A-1342, 1343

Raleigh's. A-1196

Schonland's. A-1152

Sellmeyer's. A-84

Solution of the uncoupled wave eqs. A-108

Storey's electron density value. A-387, 1201

van der Wyck's tensor method. A-682

Wave eqs. A-98

Wave packet method. A-569

IV. MODELS

1. Ionospheric models. A-ll, 23, 93, 96, 98, 110, 147, 179,

217, 220, 250, 265, 266, 268-272, 278, 284, 303,

344, 383, 389, 411, 417, 468, 472, 574, 630, 632,

637, 652, 659-663, 744, 745, 759, 805, 807, 818,

843, 846, 1025, 1126, 1133, 1179, 1269, 1270,

1283, 1336, 1369, 1381

2. Ionization models. A-82, 93, 247, 243, 359, 537, 538, 596,

597, 598, 631, 651, 670, 689, 703, 789, 811, 837,

927, 928, 944, 945, 975, 1022, 1054, 1087, 1118,

1174, 1265, 1357, 1366

3. Wave propagation models. A-215, 264, 358, 387, 388, 393,

409, 410, 427, 433, 449, 524, 569, 575, 681, 682,

684, 741, 832, 869, 878, 884, 886, 887, 910, 974,

1016, 1017,1055, 1057-1062, 1067, 1085, 1143,

1144, 1177, 1272, 1311, 1334

4. The "tarnished mirror" model. A-1175

V. IONOSPHERIC STRUCTURE AND CHARACTERISTICS

Ionospheric variations

Diurnal A-871, 1280

Seasonal A-871

Latitudinal A-595, 597, 961, 998

Longitudinal A-273-175, 431, 443, 445, 446, 699, 702, 782,

906, 1191
ix

Ionospheric horizontal structure A-299, 300, 924, 925, 1365

Diurnal variation A-157, 1126, 1127, 1377

Seasonal A-1363

Ionospheric fine structure A-223, 546, 710, 949, 1217, 1327,

1334

Cloud formation A-357

Ionized cloud patches A-128, 261, 297, 306, 576, 613, 1077,

1148, 1176, 1186, 1206, 1319

Blanketing type A-297

Thin layer A-297

Layer formation A-71, 237, 238, 400, 599, 671, 676, 691, 734,

839, 843, 1006, 1021, 1381, 1382

Layer tilts A-244, 1046, 1050, 1179, 1261, 1328, 1330

Ionizing layers A-38, 40, 114, 153, 247, 252, 261, 303-305,

384, 676, 691, 1049

C - layer A-407, 1340

D - layer A-163, 176, 199, 201, 208, 230, 312, 356, 398, 414,

431, 438, 444, 472, 491, 503, 533, 640, 667, 674,

688, 750, 782, 843, 885, 887, 893, 928, 943, 944,

953, 957, 1083, 1111, 1188, 1285-1287, 1314, 1345,

1347, 1388

E - Region A-3, 12, 35, 43, 52, 53, 55, 57, 59, 67, 73, 76, 78,

79, 82, 84, 94, 97, 131, 145, 148, 162,163, 176,

191, 198, 199, 201, 216, 231, 243, 257, 279, 290,

310, 341, 342, 367, 374, 382, 423, 439, 450, 468,

482, 496, 503, 520, 521, 523, 528, 545, 563, 574,

599, 624, 640, 651, 652, 667, 670, 688, 714, 727,

740-742, 748, 749, 766, 767, 811, 822, 833, 834,

842, 844, 866, 881, 885, 887, 902, 909, 928, 953,

957, 962, 963, 1007, 1016, 1027, 1031, 1032, 1038,

1049, 1072, 1077-1079, 1084, 1089, 1090, 1111,

1129, 1135, 1179, 1196, 1220, 1222, 1231, 1259,

1299, 1303, 1315, 1327, 1336, 1342, 1345-1347,

1358, 1369, 1376, 1385, 1388

E^ layer A-141

E

2

layer A-141, 142, 1066

E layer A-20, 31, 111, 120, 148, 151, 153, 165, 169, 177,

198, 241, 257, 258, 261, 297, 346, 351, 382, 390,

419, 438, 449, 454-456, 458, 459, 483, 512, 547,

588, 613, 629, 727, 733, 761, 767, 782, 786, 790,

915, 918, 933, 984, 1019, 1025, 1034, 1110, 1157-

1159, 1189, 1205-1207, 1243, 1245, 1258, 1311,1315
Polar E . A-933, 1158

s Variations

Diurnal A-260, 468, 477, 505

Seasonal A-460, 483, 786

Annual distribution A-460

E Analysis. A-128, 165, 225, 372, 576

Movement A-450, 453-456, 458, 460, 477, 515, 528,

733, 790, 902, 1008, 1045, 1319,

Frequency A-128, 181, 351, 545

Intensity A-128

World Wide drift A-225, 1157, 1160

Spiral occurrence A-510

Classification A-1208

F - Region A-12, 27, 57, 73, 131, 145, 153, 176, 187, 241, 244,

279, 290, 298, 373, 407, 423, 433, 472, 478,

496, 503, 570, 624, 670, 714, 733, 739, 740,

746, 754, 805, 809, 810, 815, 816, 844, 872,

953, 991, 1016, 1038, 1042, 1049, 1067, 1089,

1090, 1121, 1220, 1243, 1259, 1299, 1319,

1321, 1342, 1344, 1345, 1366, 1385

Characteristics

Disturbances A-145, 151, 170, 172, 186, 203, 213, 305,

331, 337, 350, 382, 406, 475, 482, 501, 517,

732, 821, 841, 901, 908, 1042, 1051, 1068,

1165, 1177, 1391

Variations

Diurnal A-157, 1126, 1127, 1377

Seasonal A-1363

Thermal equilibrium A-135

F, Region A-43, 52, 67, 78, 503, 1066

F9 Region A-31, 33, 50, 52, 60, 64, 68, 69, 72, 78, 81, 106, z

118, 130, 132, 170, 276, 337, 341, 350, 368,

381, 438, 449, 462, 503, 517, 562, 614, 642,

677, 728, 733, 812-814, 933, 992, 1012, 1127,

1128, 1149, 1166, 1245, 1256, 1351, 1376-1380

Vertical movement A-1011

Horizontal movement A-170, 182, 186, 235, 260, 279, 529,

647, 813, 1014, 1216, 1223, 1246
Critical frequency (Max. ionization) A-59, 60, 65, 81, 93,

113, 118, 157, 167, 174, 195, 196, 214, 275,

276, 298, 330, 332, 341, 382, 536, 828, 880,

998, 999, 1008, 1038, 1060, 1091, 1121, 1148,

1203, 1252, 1303, 1322, 1383

Spread F (Triple split) A-lll, 194, 220, 243, 394, 396, 497,

787, 945, 1020, 1028, 1032, 1060, 1062, 1067,

1076, 1116, 1171, 1252, 1363

Irregular movements and other variables

Winds and drifts A,-9, 23, 32, 108, 122, 125, 127, 128, 145,

170, 191, 259, 260, 279, 294, 318, 319, 354,

361, 377, 404, 405, 415, 416, 419, 490, 515,

519, 520-525, 573, 577, 581, 647-649, 654,

692, 731, 754, 758, 761, 796, 800, 801, 833-

835, 867, 870, 909, 947, 985-989, 991, 992,

995, 1004, 1007, 1036, 1045, 1048,1068, 1100,

1126, 1130, 1146, 1154, 1195, 1314, 1339,

1350, 1356, 1358, 1372-1374, 1397, 1404

Storms and disturbances SID A-245, 247, 281, 290, 311, 440,

490, 572, 591, 629, 646, 656, 813, 841, 870,

871, 902, 957, 980, 985, 1008, 1051, 1068,

1150, 1165, 1177, 1250, 1253, 1296, 1299,1312,

1338, 1354, 1388

F-region disturbances q. v. Nuclear explosions A-331, 1178, "1242

(PSC) Pulsation sudden commencements A-1289

(SEA) Sudden enhancement of atmospherics q. v. X-ray bursts A-431

Atmospheric waves A-573, 1185

Oscillatory movement A-1147

Spherical ripples (in the ionosphere) A-1023

Scattering A-143, 144, 222, 257, 310, 428, 435, 453,

1077, 1078

Density A-528, 923, 925

Conductivity A-107, 108, 228, 667, 670, 672, 910

Pressure A-197, 528

Damping A-141, 157, 750, 1092

Temperatures A-99, 135, 191, 197, 199, 441, 445, 528,

580, 667, 668, 821, 843, 893, 925, 931

Thermal equilibrium A-135
XI

Ionospheric screening effect A-910, 1290

Electrical (Hall) currents A-107, 108, 128, 280, 281,

347, 580, 758, 789, 895, 1140, 1141, 1254,

1314, 1357, 1387

Ionospheric magnetic fields A-591, 680, 1387

Magnetic activities A-186, 192, 196, 243, 387, 517,

1264, 1272, 1289, 1357, 1363

Dipoles A-1264-1266, 1272

VI. STATISTICAL ANALYSIS A-23, 31, 106, 123, 126, 137, 148, 172,

209, 242, 287, 391, 531, 577, 581, 583, 738,

748, 806, 835, 839, 843, 915, 1004, 1014, 1044,

1100, 1187, 1293, 1294

VII. PHYSICO - CHEMICAL FACTORS AND PROCESSES

Ionization A-43, 49, 50, 62, 82, 83, 85, 99, 128, 135, 195,

197, 198, 224, 238, 239, 241, 257, 276, 277,

348, 354, 382, 496, 567, 570, 578,579, 591,

593, 594, 599, 613, 616, 659, 680, 714, 730,

733, 748, 749, 788-801, 814-816, 825, 829, 83Q

843, 855, 877, 893, 904, 925, 967,996, 998,

1027, 1041, 1090, 1180, 1319, 1357

Horizontal gradient A-116

Variation A-118, 238

Ionograms A-13, 111, 151, 157, 252, 277, 386, 667, 727,

786, 788, 810, 817, 964, 1011, 1012, 1027,

1087, 1103, 1109, 1158, 1182, 1189,1212, 1220r 1222, 1242, 1303, 1305, 1327, 1360-1362, 1398

Ion density A-578, 579, 616, 642, 670, 943, 944, 996, 1098

Ion composition A-641

Heavy ions A-571, 1005

Ionizing agents

Hydrogen A-1182

Protons A-594

Satellites A-1041

Molecular density A-439, 476, 598, 673, 926
Xlll

Electron density A-21, 27-30, 35, 73, 75, 85, 101, 114, 116,

120, 132, 139, 147, 151, 152, 176-178, 187,

192, 197, 222, 224, 237, 247, 250, 252, 271,

277, 278, 284, 288, 303, 328, 338, 339, 374,

386, 387, 400, 407, 414, 418, 426, 432-439,

440, 442, 444, 447, 468, 471, 496, 536-538,

567, 578, 579, 580, 591, 593, 624-627, 651,

659, 668, 670,677, 689, 714, 725, 728, 735,

740, 745, 805, 807-810, 812, 817,819, 830,

843, 844, 887, 895, 925, 943, 982, 1010-1012,

1030, 1033, 1050, 1052, 1054, 1087, 1098,

1105-1110, 1113, 1115, 1118,1125, 1155, 1188,

1212, 1213, 1220-1222, 1255, 1285, 1303, 1315,

1327, 1335, 1337, 1345, 1361, 1362, 1366, 1367,

1376-1382, 1385, 1398

Fluctuations A-440, 441, 844, 947

Diurnal variation A-139, 157, 276, 328, 431, 464, 825, 843,

996, 1090, 1125

Seasonal variation A-139, 157, 276

Collision frequency A-28, 48, 51, 82, 84, 101, 132, 147, 199,

239, 258, 261, 271, 327, 393, 412, 414, 444,

473, 537, 563, 623, 670, 674, 685, 830, 950,

1005, 1016, 1024, 1031, 1050,1084, 1145, 1344-

1346

Friction A-5

Electron radiation A-1005

Electron height at max. ionization level A-257, 288, 421, 684,

880, 881, 1245

Electron density at max. ionization level A-165, 298, 400,

567, 594, 685

Mass motion and velocity A-108

Virtual height vs. frequency A-40, 42, 55, 119, 123, 137,

174, 187, 196, 257, 263, 278, 332, 373, 496,

543, 624, 691, 703, 779, 880, 1091, 1105, 1148,

1183, 1193, 1206, 1299, 1346,

Recombination A-53, 67, 99, 197, 599, 733, 953, 1285,

1287, 1335, 1376

Height vs. time data A-1247

Reflection A-19, 35, 38, 92, 97, 98, 102, 103, 112, 116, 153,

158, 243, 255, 274, 303, 304, 366, 381, 383,

384, 410, 419, 425, 426, 436, 449, 462, 470,

491, 499, 500, 546, 560, 561, 570, 581, 651,

659, 682, 695, 697, 735, 822, 856, 877, 953,

972-975, 1008, 1033, 1041, 1070-1072, 1074,

1088,1132, 1161, 1171, 1174, 1175, 1184,1244,

1267-1269, 1277, 1281, 1347, 1368, 1375, 1395
XIV

Multiple reflections A-112, 134, 183, 286,

Scattering A-27, 113, 116, 117, 131, 143, 231, 234, 411,

509, 516, 1008, 1077, 1176, 1226, 1321, 1322,

1334-1336,

Vertical incidence A-113, 116, 153, 161, 163, 165, 219,

230, 234, 241, 268, 269, 342, 403, 413, 417,

426, 444, 455, 466, 478, 492, 516, 538, 586,

630, 738, 833, 866, 902, 1076, 1099, 1101-

1103, 1116, 1159, 1193, 1242, 1246,1247, 1296,

1301, 1308, 1327, 1341, 1344, 1350, 1364

Oblique incidence A-103, 105, 129, 165, 181, 183, 205, 211,

223, 226,241, 269, 349, 362, 466, 537, 540,

704, 755, 860, 997, 1096, 1137, 1138, 1158,

1167, 1189, 1265, 1312, 1351

Steep incidence A-240

Z-incidences A-394, 1076

Refraction A-43, 54, 93, 100, 247, 303, 304, 590, 623, 632,

725, 744, 745, 924, 925, 1165, 1252, 1317, 1318,

1337, 1355

Diffraction A-217, 231, 242, 255, 256, 411, 1000,1002, 1044,

1279

Splitting A-133, 885, 945, 1171, 1299

Triple split (See Spread F)

Bifurcation A-lll, 298, 805, 806, 811, 945, 1020, 1108,

1129, 1171, 1252, 1256

Absorption A-8, 11, 19, 82, 84, 89, 91, 100, 110, 123, 130,

157, 161, 162, 183-185, 199, 201, 295, 379,

403, 413, 464, 473, 504, 630, 643, 677, 757,

824, 832, 855, 893, 958-961, 974, 975, 990,

993, 1005, 1016, 1021, 1031, 1086, 1089,1096,

1111, 1113, 1121, 1131, 1153, 1174, 1200, 1285,

1308, 1342, 1343, 1376

Diurnal variation A-855, 1096

Seasonal variation A-202, 364, 743, 960, 1285

Attenuation A-229, 325, 856, 1033, 1202, 1268, 1295, 1344

Modulation A-1292

Interaction A-333, 412, 414, 563, 564, 596-598, 705, 856,

1257

Gyro-interaction A-334, 335, 478, 562, 564, 866

Self-demodulation A-101, 336, 705, 719, 778
rv

Polarization A-5, 39, 41, 44, 54, 58, 88, 100, 105, 147, 211,

239, 247, 268, 342, 417, 418, 468, 540, 545,

567, 586, 587, 686-688, 695, 697, 737, 738-

740, 744, 784, 855, 884, 1050, 1075, 1076,

1090, 1099, 1145, 1198, 1291, 1297, 1299,

1308, 1314

VIII. WAVE CHARACTERISTICS

Propagation

Frequencies

LF ( < 300 kc, 10-1 km ) A-ll, 25, 91, 122, 123-125,

147, 161, 162, 173, 205, 212, 223, 230, 240,

268, 287, 289, 342-345, 397, 399, 403, 410,

417, 451, 468, 471, 484, 543, 544, 546, 547,

551, 552, 554, 582, 589, 649, 651, 697, 709,

750, 833-835, 884, 928, 972, 1065, 1068, 1089,

1101, 1191, 1193, 1232, 1247, 1295-1299, 1301,

1305, 1308, 1312, 1323

VLF(<30kc, 100-10 km ) A-25, 102, 103, 105, 204,

229, 230, 235-238, 271, 285, 291, 325, 326,

397, 434, 437, 442, 443, 445, 530, 531, 556,

557, 583, 585, 586, 637, 702, 709, 717, 741,

784, 791, 886, 904-906, 943, 972, 1003, 1065,

1073, 1166, 1174, 1175, 1184, 1191, 1197,1202,

1267, 1268, 1270-1276, 1278, 1280, 1282, 1283,

1294, 1369, 1394

MF « 3 Mc, 1000-lOOm ) A-9, 11, 12, 36, 47, 97,

141, 145, 149, 185, 191, 200, 230, 241, 243,

251, 259, 279, 395, 412, 413, 420, 421, 444,

446, 471, 484, 485, 491, 544, 552, 588, 1219,

1223, 1301, 1319, 1342, 1343, 1345, 1350, 1373,

1374

HF(3-30Mc, 100-10m ) A-2, 3, 7, 9, 14, 19, 20,47,

84, 145, 149, 158, 170, 185, 200, 206, 227,

241, 245, 292, 306, 310, 348, 349, 393, 396,

463, 483, 484, 492, 494, 516, 527, 533, 561,

856, 857, 859, 862, 863, 872, 880, 924, 925,

932, 939, 971, 980, 1010, 1076, 1077, 1083,

1105, 1116, 1117, 1137, 1174, 1179, 1196,

1246, 1261, 1285, 1288, 1301, 1341, 1343,1345,

1350, 1352, 1370, 1371, 1373, 1374

VHF (30-300 Mc, 10-lm ) A-31, 94, 104, 114, 123,

134, 139, 145, 165, 173, 210, 221, 222, 231,

246, 301, 316, 321, 329, 350, 351, 369, 390,

399, 419, 423, 428, 449, 450, 454, 456, 458-
XVI

Frequencies - cont'd. _

460, 492, 495, 498, 499, 502, 503, 507, 508,

533, 541, 559, 560, 567, 581, 611, 613, 614,

706, 712, 770, 777, 781, 783, 1077, 1079,1157,

1159, 1165, 1167, 1169, 1171, 1179, 1190,1194,

1200, 1317, 1329, 1334-1337, 1353-1355, 1388

UHF (300-3,000 Mc, 10-1 dm AJ A-27, 51, 356, 366,

404, 498, 621, 768, 836, 837, 919, 947, 1028

1077, 1156, 1355

SHF (3, 000-30, 000 Mc, 10-1 cm A ) A-51, 583, 919,

1077, 1156, 1355

EHF (> 30,000mc, <!l0mm M A-496, 500

Gyro frequency A-92, 99, 335, 478, 564

Diurnal variation A-341

Long range propacration A-16, 19, 20, 24, 102, 105, 140, 185,

204, 206, 210, 214, 235, 236, 243, 245, 246,

317, 326, 366, 371, 391, 395,423, 461, 466,

467, 518, 541, 546, 595, 613, 715, 718, 746,

752, 829, 831, 862, 863, 869, 900, 902, 916,

918, 919, 955, 962, 963, 1052, 1055, 1067,

1073, 1085, 1095, 1104, 1263, 1275, 1277,1295,

1347, 1355, 1368, 1385

Lateral deviation A-858, 859

Scatter propagation A-91, 104, 147, 234, 254, 264, 302, 329,

350, 363, 367, 399, 423, 441, 447, 492, 500,

507-509, 559, 581, 613, 645, 678, 706, 707,

712, 717, 720, 800, 858-900, 908, 913, 1077,

1335-1338, 1348, 1352-1354, 1388

Scatter sounding A-1258, 1259, 1261

Propagation media

Plasma A-197, 475, 568, 579, 679, 730, 745, 922, 950,

954, 1024, 1335, 1337

Outer atmosphere A-387

Z-propagation hole A-396

Single F-hop propagation A-371

Meteor forward scatter A-423, 581, 1077, 1078

Arctic propagation A-4, 48, 227, 315, 382

(IE) Trans equatorial propagation A-31, 321, 1261, 1262

Tropical propagation A-244
XV11

Back scatter A-3, 253, 263, 394, 527, 858, 859, 1122, 1123,

1134, 1135, 1138, 1176, 1246, 1258, 1259,1322

From ground A-306, L179, 1258

From sea A-306, 575, 1172, 1258

Laboratory sea wave models A-1172

Propagation of satellite signals A-305, 613, 620

Magneto-ionic duct propagation A-553

Influencing factors

Solar influences

Chromosphere A-599

Solar corona A-473, 836

Solar activities A-43, 52, 78, 87, 142, 193, 301, 399,

554, 595, 634, 700, 714, 715, 748, 749, 806,

840, 855, 953, 967, 969, 1063, 1150, 1184,

1203, 1298, 1301

Sunspots A-14, 56, 62, 64, 66, 135, 166, 167, 273, 334,

346, 406, 743, 825, 921, 969, 1084, 1150, 1302

Sunspot cycles A-252, 273, 793, 1015

Solar flares A-103, 198, 593, 699, 751, 904

Solar radiation A-9, 237

Diurnal variation A-110

Corpuscular radiation A-157, 368, 939, 1186, 1319

Unusual radiation A-301

Equinoxes A-81, 157

Eclipses A-49, 216, 237, 608, 1033, 1383

Extraterrestrial Influences A-2, 201, 220, 836

Radio astronomy A-566, 574, 608, 1013, 1162, 1321

Satellite motions A-1292

Outer atmosphere (space) A-21, 29, 209, 267, 636, 932

Meteors A-59, 101, 128, 210, 399, 423, 647, 800, 1052,

1117, 1354

Upper atmospheric influences

Stratosphere A-228, 479, 667

Mesopause A-1110

Magnetic storms A-69, 78, 89, 91, 196, 227, 281, 301,

517, 591, 595, 737, 743, 969, 1253, 1300, 131S

Electrostatic fields A-407

Ionization belts A-267, 932, 1387

Radio Astronomy A-1284-1288, 1355

Radio Star scintillation A-770, 815, 816, 821, 836,

1007, 1148, 1321

Air glow A-101, 431
XV111

Upper atmospheric influences - concl'd.

Auroral zone A-1332

Auroral activities A-7, 87, 153, 157, 227, 301, 348,

388, 369, 390, 406, 516, 969, 1031, 1052,

1186, 1357

Atmospheric influences

Troposphere A-137, 377, 423, 440, 541, 644, 645, 836,

892, 900, 1052, 1064, 1077, 1079, 1118, 1162,

1248, 1318, 1334,

Arctic troposphere A-87

Acoustic wave effects A-1226

Meteorological elements A-163, 541, 644, 698, 754, 827,

861, 881, 898, 1404

Pressure A-829, 830, 881

Temperature A-667, 893, 925

Weather A-425, 1080

Radiation A-397

Relative humidity A-836

Fog A-1156

Fronts A-137, 157

Anticyclonic circulation A-450

Hurricanes A-138

Rain A-1156

Thunderstorms A-25, 158, 297, 584, 585, 892, 1039,

1065, 1082, 1094, 1180

Lightning A-897, 1039, 1052, 1088, 1118, 1170,

1198, 1323

Nuclear explosions A-702, 941, 1178, 1242

Terrestrial influences

Geomagnetism A-7, 13, 34, 37, 62, 65, 68, 78, 83, 87,

92, 129, 146, 166, 275, 276, 377, 382, 386,

394, 410, 424, 426, 476, 493, 512, 516, 559,

655, 792, 819, 838, 897, 1019, 1031, 1095,

1149, 1150, 1214, 1252, 1300, 1335, 1371,1397

Topography A-423

Knife edge A-1194

Waves

Phase difference A-326, 752, 767, 854, 981, 1184, 1198,

1204, 1217, 1263

Phase velocity A-1280

Group velocity A-869, 1280

Extraterrestrial radio waves A-725, 732, 770, 954, 961, 1063
XIX

Sun emitted waves A-93, 954

"Magnetic" sound waves A-954

Magneto-hydrodynamic waves (Alfven A ) A-13, 387, 388,

966, 1290

Sky waves A-13, 173, 204, 548, 965, 1017, 1184, 1267,

1295, 1312

Pedersen rays A-955

Ground waves A-36, 204, 797, 798

Gyro waves A-101, 333, 1098, 1145

UV - energy A-432, 496

Fading A-94, 127, 219, 230, 231, 255, 256, 279, 293, 296,339,

421, 438, 498, 519, 530, 534, 540, 639, 722,

732, 741, 902, 951, 995, 1000, 1002, 1007,

1147, 1165, 1171, 1195, 1253, 1331, 1336, 1371-

1375, 1392

Diurnal variation A-193

Periodic variation A-694, 1142r 1144, 1196

Seasonal variation A-194

Fading pattern classification A-114, 115, 122, 126, 154, 191,

301, 1144, 1196, 1228

Faraday effect A-339, 340, 565, 567, 979, 1010, 1165

Dellinger fadeouts A-699

Doppler effect A-924, 1010, 1045, 1313, 1316, 1349

Mogel-Dellinger effects A-1083

Cotton-mouton effect A-924

Reciprocity A-109

Satellite Doppler measurements A-1199, 1210, 1217

Record analysis A-1053, 1187

Rate of fading A-210, 233, 718, 899, 1159

"Fast" fading A-191, 230, 421, 694, 841, 902, 929, 1116

"Slow" fading A-191, 230, 694, 929, 994, 1093

Random fading A-1196

Fading of satellite signals A-233, 565, 620, 677, 710,

711, 924, 1165, 1199, 1210

Fading velocity distribution A-121, 124, 230, 252, 995

Blackouts A-8, 762, 1242

Polar blackouts A-431, 766

Autocorrelograms A-125, 219, 1190
XX

Applications

Upper wind measurements A-519.-522, 524, 691

Distant sea wave measurements A-533

Theoretical oscillatory movement of ionosphere A-1147

Echoes

Echo Classification

D-echoes A-223, 397, 414, 794

E-echoes A-198, 253, 258, 261, 420, 422, 589, 696,

727, 739, 761, 766, 1090, 1116, 1244

F-echoes A-198, 245, 253, 261, 420, 821, 938, 1116,

1244, 1311

Z-echoes A-393, 394, 396, 1311

Delayed echoes A-755, 937, 938, 951

Short delayed echoes A-42

Long delayed echoes A-248, 267, 470, 777, 932

Multi-hop delayed echoes A-329, 778, 780, 833,

834, 856, 1020, 1090, 1097, 1311

Short-lived echoes A-1117, 1190

Weak echoes A-474, 485

Night echoes A-253, 787

Coupling echoes A-767, 929

Split echoes A-lll, 194, 220, 243, 298, 394, 396, 497,

560, 787, 885, 945

Left-handed M echoes A-696

Peculiar echoes A-913, 939, 1097

Echo analysis A-365, 766, 780, 787, 1352

Diurnal variation A-422, 774

Seasonal variation A-422, 774

Periodicity A-287

Dependency on illumination A-95

Components A-546

Amplitude A-251, 261

Phase A-249, 251, 420, 589, 752, 767, 778, 865

Focusing effect A-494, 732, 937, 1020, 1021, 1023

Directional reception A-1219

Antipodal A-305, 620, 859, 923, 1165, 1329

Echo reflectors (positive)

Auroras A-753

Artificial electron clouds A-436

Ion belts A-267, 1387
XXI

Echo reflectors (Passive)

Balloons A-S67

Meteors A-94, 399, 753, 774, 800, 801, 1007

Moon A-29, 93, 139, 338, 567

Satellites A-155, 232, 620, 728, 729, 787

Sea waves A-533

IX. RADIO COMMUNICATION

Technical problems, general A-310, 1036, 1248, 1354,

Radio communication disturbances

Storms, etc. A-158, 168, 329, 449, 584, 629, 656, 708,

792, 921, 947, 1051, 1150, 1391

Nuclear explosions A-762, 819, 941

SC A-875

Transmission blocking A-1051

Frequency allocations A-644, 645

Measurements A-664

Maintenance A-154

Teleprint A-329

FM teletype systems A-900, 1192

FM radio relays A-900

Television A-708, 1194

Navigation aids A-1248, 1251

Radio navigation A-1251

Radio communication

At sea A-434, 913, 921, 1051, 1348

In space A-567, 620, 663, 711, 936, 1165, 1292,

1311, 1349

In air flights A-842

Transoceanic A-956

By the Pedersen beam A-1022

Sferics A-2, 25, 87, 103, 229, 265, 266, 286, 443, 493, 545,

556, 584, 585, 587, 595, 600, 608, 617-619,

637, 665, 666, 695, 698-700, 702, 722, 735,

736, 750, 783, 878, 879, 883, 904-906, 931,

1033, 1039, 1065, 1070-1073,1082, 1088,1093,

1094, 1152, 1170, 1192, 1197, 1198, 1202,

1293, 1294, 1323, 1400

Classification A-286, 291, 558, 698, 700, 735, 883, 1088,

1198

Accuracy of spotting A-1152

Diurnal variation A-158, 700, 1065, 1082

^M^^M^H
xxii

Classification - concl'd.

Frequency A-291, 292, 554, 666, 698, 722

Periodicity A-554

Distribution A-878

Intensity A-665, 699, 700, 1065

Slow tails A-557

S.E. A. (Sudden enhancement of atmospherics) A-1065

Noise A-284, 301, 554, 583, 840, 931, 1151, 1271, 1302

Noise temperature A-936

Noise level

Diurnal variation A-751, 1191

Seasonal variation A-1191

Annual variation A-751

Networks A-324, 1202

National and local noise level predictions A-323, 324, 347, 451,

1191, 1370

World wide noise level predictions A-323

Hiss A-284, 442, 1300

Dawn Chorus A-284, 442, 549, 864, 977, 1300, 1400

Diurnal variation A-997

Whistlers A-21, 272, 322, 355, 376, 380, 442, 447, 550, 551,

553, 617-619, 701, 726, 861, 864, 897, 922,

1039, 1040, 1118, 1182, 1201, 1300, 1304, 1400

Diurnal variation A-701

Seasonal variation A-701

"Nose" whistlers A-549

Cos mic noise A-157, 316, 1031, 1285-1288, 1400

Absorption A-1287, 1288

Refraction A-1288

Radio communication forecasting A-14, 61, 73, 96, 214, 351,

425, 513, 514, 518, 527, 541, 584, 629, 683,

724, 823, 876, 969, 1014, 1069, 1119, 1138,

1156, 1234, 1258, 1260

Spontaneous path predictions A-1260

Winds A-692

MUF A-4, 10, 20, 57, 61, 70, 92, 115, 145, 160, 168, 181,

184, 330, 350, 356, 360, 373, 466, 513, 514,

685, 779, 793, 857, 858, 982, 1015, 1135, 1138,

1158, 1166, 1189, 1214, 1234, 1255, 1258,1261,

1351
XXI11 MUF - concl'd.

Diurnal variation A-1015

Seasonal variation A-181

Calculation A-1214

MUF, German method A-1015

LUHF A-14, 168, 514, 857, 858, 982

Choice of frequency A-95, 96, 201, 350, 466, 971, 1069,

1204, 1232

Radio communication, forecasting accuracy A-1150, 1351

Radio-visual forecasting method A-828

Direction finder technique A-527

Networks and storm warning systems A-166, 489, 584, 656,

657, 724, 876, 1119, 1164, 1234

Transmission modes

Experimental transmissions A-102, 109, 141, 191, 204, 245,

312, 321, 325, 380, 475, 480, 492, 507, 508,

596, 614, 615, 706, 713, 716, 787, 827, 833,

860, 908-910, 937, 955, 963, 967, 983, 1134,

1137, 1166, 1194, 1220, 1225, 1253, 1298,

1338, 1388

Space exploration A-636, 663, 729, 922-924, 940, 947, 978,

1013, 1047, 1081, 1387, 1403

Exosphere A-1040

Rocket transmissions A-621-623, 627, 663, 728, 983, 1104-

1110, 1112, 1114, 1115, 1140, 1141, 1385,

1387

Satellite transmissions A-178, 233, 506, 535, 615, 620, 663,

677, 710, 711, 728r730, 923, 924, 956, 1010,

1081, 1165, 1199, 1245, 1292, 1311, 1313, 1316,

1349, 1385, 1391

Satellite tracking A-506, 526, 620, 914, 923, 942

Satellite orbit predictions A-179, 711, 947

Satellite orbit characteristics A-506, 1010, 1245, 1292

Electrohydrodynamic drag A-730

Ionized hydrogen A-922

Whistler mode transmissions A-380

Phase-shift keying systems A-721
XXIV

X. METHODS AND TECHNIQUES OF OBSERVATION

Aircraft A-841

Analysis methods of ionospheric movement records A-1043

Beacon techniques A-352

Breit and Tuve's method A-484

Combined sweep and fixed frequency techniques A-1320

Continuous wave method A-582, 627

Control -line method A-857

Control -point methods A-857

Counter techniques A-892

Direction finder techniques A-527

Directional drift method A-477

Doppler method A-29f 75, 533, 720

Dynamic probe technique A-578

Echo methods A-1231, 203

Tuve and Hafstad's method A-249

Graphical methods re. Ray-tracing A-868

transmission loss vs. distance and antenna heights A- 1035

Wave paths A-971

I. P. S. (Australia) method A-857

Impulse absorption methods A-232

Impulse echo methods A-172, 311, 545, 546

Instrumental correction methods A-779

Ionospheric investigation methods A-43

Langmuir's probe technique A-579, 580

Machine computation methods A-350, 418, 532

Of scattering A-678

Magnetometer flights A-280

Mitra's method A-515

Modulation techniques A-717

Nomogram and slide rule method A-360

Phase measuring techniques A-173, 236, 752
XXV

Methods and techniques of observation - cont'd.

Prediction techniques A-823

Pulse sounding techniques A-582

Pulse technique A-1298

Putter technique extended A-126, 172

Radar target tracking methods A-32

Radio communication forecasting methods A-518

Radio methods A-1358, 1404

Winds A-801, 1358

Radio "rise" and "set" method A-29, 30

Recording method of disturbances over certain distances A-792

Reduction methods

Of Doppler shift errors A-720

hf records to Nh profiles A-1087, 1220, 1221, 1361, 1362

RF-probe technique A-625, 626

Rockets A-18, 29, 32, 180, 226, 278, 280, 337, 392, 400,

429, 496, 502, 528, 579, 599, 616, 621-625,

627, 641, 674, 728, 756, 775, 807, 314, 824,

830, 890, 946, 949, 983, 1104-1110, 1112,

1114, 1115, 1140, 1229, 1239, 1381, 1403

Satellites A-28-30, 155, 177, 178, 209, 220, 283, 305, 398,

535, 580, 613, 616, 728-730, 891, 923-925,

940, 941, 946, 956, 1010, 1041, 1047, 1165,

1292, 1313, 1316, 1349, 1391, 1394, 1403.

Alpha I. A-613, 1081

Alpha II. A-1081

Beta A-620

Explorer VI. A-1394

Sputnik I. A-924, 1010, 1165

Sputnik II. A-924

Sputnik III. A-305, 930

Sferics observation techniques A-291, 665

Photography technique A-286

Synchronic recording A-1151

Similar fades method A-1350, 1373, 1374

Six-point correlation method A-1350, 1373, 1374

Sounding methods A-1359
XXVI

Methods and techniques of observation • concl'd.

Spaced receiver method A-290, 296, 301, 318, 354, 529, 530,

646, 649, 679, 731, 833, 834, 853, 872, 902,

920, 924, 940, 985-987, 989, 995, 1004, 1046,

1053, 1146, 1190, 1216, 1223, 1350, 1373

Sweep frequency pulse techniques A-10, 146, 181

Tuned amplifier method A-1197

Visual radio reception method of atmospheric conditions A-828

Upper air wind measurement methods A-32, 127, 290, 318, 404,

405, 853, 817, 1372

Krautkramer's method A-519, 522, 524

Meteor methods A-801

Wave guide modes A-271

Weather forecast methods

Gherzi's method A-462, 463

Miscellaneous techniques

Pressure A-75

Absolute temperature of the ionosphere A-432

Absorption A-379, 403, 639, 1200

Non-deviate absorption A-ll

Refraction A-93

Oblique incidence A-223

Diffraction effects A-242

Coupling effects A-147

Circular polarization A-58

Polarization A-39

Ionization A-55

N(h) electron density A-120, 146, 149, 150-152, 187, 339

Lunar echo method A-139

Booker-Seaton's method A-146, 152, 802

Electron density of interplanetary space A-431

Electron collisional frequency A-48

Height of irregularities giving rise to fading A-123

True height of layers A-85, 151, 187, 202, 842, 1364

Virtual height A-964
XXVI

Miscellaneous techniques - cont'd.

Group height A-ll, 471

Phase height A-ll, 650

Optimum antenna height A-827, 900

Chance coincidence/whistlers A-322

Energy trajectories A-S6

Earth's magnetic field A-336

Optimum MUF A-160

Sky wave problems A-548

Sky wave field intensity A-788

F layer propagation lower frequency limit A-433

Nocturnal propagation A-391

Radio amateur observations A-1034

Ship observations A-1051

Numerical solutions of differential eqs. A-269, 413

Survey of methods

Of measurements A-465

For upper atmosphere information A-1249

For sferics measurements A-864

Of direction finding of whistlers A-1304

XI. INSTRUMENTS, EQUIPMENT, SYSTEMS

Antennas A-785, 826, 828, 858, 911, 1348

Rhombic antennas A-1190

Yagi antennas A-1190

Rocket antennas A- 621, 826, 1239-3240

Dipole antennas A-1101, 1102, 1353

Telemetering notch antennas A-502

VLF antennas A-784

Multiple-wire Delta antennas A-314

Instrumentation

For ionospheric research A-553

For phase height A-589
XXV111

Equipment

Laboratory equipment for simulated ionosphere A-1230

Mobile ionospheric research stations

Tractor A-1392

Automatic measurement equipment A-163, 173, 263

Absorption measuring equipment A-959

Height measuring equipment

For vertical incidence A-484, 1364

Delta phase height equipment A-650

Impulse equipment A-969

Wide-deviation reaction modulator equipment A-768

Sounding Systems

Sounding equipment A-109, 133, 480, 762, 874, 1049

Backscatter sounders A-1123, 1176

Echo-sounding apparatus A-1091

lonosondes A-933

c-2 A-1242

IGY 3-frequency back-scatter sounder A-942

Mullard radar sonde system A-525

Rawin sets A-722

Sounding recorders

Model C-4 A-1301

Transmitter and Receiver Systems

Missile tracking systems

DOVAP A-176, 177

Receivers

Signal Corps BC 969. A-1191

Signal Corps BC 779. A-1191

Even-Knight radio astronomy receiver. Model 1620.

A-1286

Synchronized transmitter and receiver A-362

Scatter communication systems A-423

Transmitters

LF pulse transmitter A-1297

Power pulse transmitter A-212

Radars A-24, 404, 405, 481, 525, 566, 577, 753, 796,

898, 940, 1036, 1048, 1052, 1099, 1117, 1261
XXIX

Rocket and Satellite

Rocket borne equipment A-622, 641, 982, 1239, 1394

Rocket cameras A-1239

Rocket transmitters A-776, 1240

Satellite equipment A-526

Satellite instrumentation

Satellite Doppler navigation system A-1316

Satellite radio receivers A-1047

Satellite radio transmitters A-1047

Direction of arrival equipment A-1204

Ionospheric thunderstorm equipment A-1180

Directionfinders A- 229, 361, 587, 692, 695, 1198

Visual and recording type A-859

Noise - Systems

Noise equipment A-451

Sferic recorders A-1197

Whistler equipment A-1201

Selective whistler detector A-355

Pseudo whistling device A-619

Miscellaneous

Bennet's ionic mass spectrograph A-616

Echo detectors

Weak echo detector A-474

Electronic computers A-1398

Frequency steppers A-592

Group retardation recorders A-42

Gyrocompasses A-921

Interferometers

Ryle's phase-switching interferometer A-1284, 1285

EHF dispersion interferometers A-496

Dispersion interferometers A-728

Magnetic compasses A-921

Modulators

Kerr modulator A-1056

Multivibrators A-505

Oscillators A-955

Panoramic ionospheric echo recorders A-765, 1181, 1319,

1320

Pulse repeaters A-404
XXX

Miscellaneous - concl'd.

Radio telescopes A-725

Radiogoniographs A-791

Lugeorr -Mobile type A-791

Radiometers A-31

6

Riometers A-772

Spectroscopes A-904

TV spectroscope A-226

Spectrometer A-641

Sweep frequency recorders A-263

Vertical incidence measurement equipment A-1308

Influence of instruments on data A-15, 17, 528, 722
XXXI

GEOGRAPHICAL OUTLINE

A. HEMISPHERES AND REGIONS

Northern Hemisphere 64, 78, 167, 460, 550, 595, 812,

875, 901, 1039, 1050

Southern Hemisphere 39, 78, 167, 550, 812, 1039,

1050

Polar Regions

South Pole 714

Tropics 72, 167, 528, 743, 920, 1153, 1363

B. CONTINENTS

1. Africa

French Africa

Dakar 438, 1083, 1363

Algeria

Algiers 70

Bani Abbes 493

Belgian Congo

Bunia 156

Karavia 156

Leopoldville 156, 1356

Ruampara 156

Gold Coast

Achimota 726

Morocco

Casablanca 533

Nigeria

Ibadan 324, 1153, 1154, 1363, 1390

Somaliland

Djibouti 1363
XXXI

1

South Africa 595

Cape Town 913

Elizabethville 156

Johannesburg 66

Pretoria 577

Transvaal 412

Southern Rhodesia

Salisbury 321

Sudan

Khartoum 1363

2. Asia

China 462

Shanghai 462

Wakkanai 501

Wuhan 501

India 1075, 1399

Ahmedabad 727, 1116, 1131

Allahabad 1227

Bakhru 696

Barnabas 1145

Benares 116, 874

Calcutta 197, 464, 985, 1066

Dacca 985

Delhi 118, 855, 993, 1147, 1166, 1253

Haringhata 341

Hyderabad 732

Khestgir 696

Kodaikanal 194, 195, 196, 984

Madras 994, 1167, 1253

New Delhi 1065, 1195

Tiruchirapalli 1253

Tirupati 1253

Vizagapatam 1153

Waltair 987, 988, 989, 990, 991, 992, 994, 1167

Japan 33, 70, 227, 608, 667-670, 701, 702, 715, 856,

857, 913, 1245

Akita 698, 909

Hiraito 902, 1228

Ibarakigen 906

Kumamoto 698

Nagoya 666, 700

Ol Observatory 916
xxxm

Japan (cont'd.

)

Tazawa 909

Tokayawa 617-619, 665, 698, 700, 877

Tokyo 380, 599, 841

Wakkanai 64, 68, 617

Macao 463

Malaya

Singapore 913, 920, 1000, 1153, 1154, 1390

Philippine Islands 134

Baguio 806

Luzon 1159

Palau 64

U.S.S.R. in Asia 227

3. Australasia

Australia 12, 16, 41, 97, 445, 595, 608, 1088

New South Wales

Canberra 90, 143, 517

Sydney 444, 566, 872, 873, 1162

Northern Territory

Darwin 380

Queensland

Brisbane 106, 588, 786, 787, 1148, 1205, 1311,

1328, 1330

Buderim 787

Toowoombe 787

South Australia

Adelaide 478

Crystal Brook 863

Whyalla 863

Tasmania

Hobart 380, 393, 394, 396

Victoria

Rockbank 1370

Western Australia

Nedlands 980

Watheroo Observatory 174, 1222
XXXIV

New Zealand 20, 140# 227, 326

Auckland 1048, 1328, 1330

Chris tchurch 64, 140, 703, 817

Lower Hutt 319

4. Europe

Western Europe 14

Belgium 609

Dourbes 791

British Commonwealth 1396

British Isles 1398

England 40, 41, 241, 423, 494, 531, 585, 586, 595,

608,615, 656, 713, 716, 777, 958, 1079, 1122,

1123, 1293, 1358

Allous 185

Birmingham 35

Cambridge 35, 171, 209, 229, 230, 237, 238, 259,

269, 286, 311, 515, 521, 646, 952, 1341,

1389, 1393

Cavendish 235, 1174

Daventry 70

Farnborough 209

Hemsby 244

Inverness 209

Jodrel Bank 301

London 35, 876, 1396

Portsdown 710

Rugby 103, 237, 238, 326, 530

Slough 66, 182, 185, 186, 200, 209, 298, 488,779,

960, 962, 1011, 1042, 1153, 1155, 1164, 1212,

1213, 1222, 1345, 1390, 1398

Shelton 185

Swaffham 1341

Tats field 166, 168

Winkfield 244, 245

Scotland

Aberdeen 103, 229, 238, 244

Brughead 488

Wales

Swansea 185, 186, 191, 960
XXXV

Bulgaria 796

Sofia 494

Czechoslovakia 1034

France

Bagneux 761, 1034

Dijon 227

Neuf-Brisach 519, 521, 522

Paris 1034

Poitiers 81, 165, 761, 1039

Saint Omer 2

Germany 561, 608

Cologne 170, 311

Freiburg 165, 185, 200, 1203

Hannover-Langenhagen 1035

Lindau 142, 148-151, 165, 367, 374

Munich 969

Potsdam 406, 969

Rechlin 969

Ulm 924

Weissenau 924

Teesen 182

Gibraltar 70, 423, 615, 713, 777

Hungary

Budapest 425

Italy

Genoa 224

Rome 214

Netherlands

de Bildt 165

Koosurjk 521

Norway 507, 581, 1034

Lillestrom,Kjeller 206, 515, 738, 739

Oslo 823, 976

Tromso1 47, 206, 274, 737, 738, 790

Spain

Tortosa 997

Sweden 608, 1034

Gothenburg 765, 1186, 1187

Kalundborg 406

Kiruna 426, 594, 766, 918

i^^^^H^HB^^Bl
XXXVI

Switzerland 608

U. S. S. R. (General and European) 6, 22, 24, 25, 26,

30, 159, 299, 300, 658, 676, 728, 763, 830,

1403,

Moscow 501

Yugoslavia 657

5. North America 450, 458, 459, 819, 1261

Alaska 227, 449, 1119

Anchorage 1119, 1194

College 528, 549, 753, 770, 915, 930

Foraker Mt. 1194

Kodiak 205

Mc Kinley Mt. 1194

Michumina Lake 1194

Nome 205

Point Barrow 1401

Canada 347, 349, 369, 451, 608, 823, 826, 1097,1401

Canadian Arctic (See "Arctic Regions"

)

British Columbia 227

Prince Rupert 348, 1153

Manitoba 1110

Fort Churchill 627, 674, 788, 1031

Newfoundland

St. Johns 706

Northwest Territories

Baker Lake 933

Point Barrow 1401

Resolute 514, 1098

Ontario 783

Ottawa 68, 109, 783, 1031

Quebec

Montreal 656

Saskatchewan

Saskatoon 428
XXXV11

6. Carribean Region

West Indies 1261

Cuba

Buantanama Bay 1259

Puerto Rico 9, 522, 1373

Mayaguez 1350, 1374

Trinidad 64

7. Central America

Panama Canal Zone

Balboa 324

Panama 288

8. Greenland

Thule 933

Labrador 1295

Mexico 459

United States 9, 10, 40, 91, 98, 122, 123, 126, 147,

168, 175, 280, 314, 349, 351, 453, 454, 459,

608, 862, 1035

Arizona

Gila Bend 1323

California 204, 305, 306, 322, 367, 784

San Francisco 916

Colorado 1237, 1286

Boulder 324, 716, 1137, 1300, 1391

Table Mesa 1159

District of Columbia (Washington) 9, 204, 214, 285,

351, 376, 506, 636, 1134, 1228, 1237, 1238,

1322

Florida

Gainesville 1191

Illinois

Long Branch 1159
XXXV111

Iowa

Cedar Rapids 351, 390, 399, 706, 967, 1159, 1190,

1348, 1388

Maryland 1322

Annapolis 553

Massachusetts 554

South Dartmouth 1348

Montana 453

Nevada 453

New Jersey

Fort Monmouth 683

New Mexico 554, 1237

White Sand 431, 527, 528, 579, 624, 627, 1105,

1107, 1108, 1387

New York 656

Ithaca 390, 1052

Pennsylvania 162, 468

State College (Univ. Park) 651, 833, 887, 1308

South Dakota 863

Virginia 324, 1322

Sterling 351, 399, 527, 697, 706, 967, 1137, 1159,

1388

Washington 66, 81, 288, 322, 514, 515, 844, 1203,

1237

Seattle 204

West Virginia 312, 1322

Wyoming

Bill 1324

9. South America 1261

Cape Horn 553

Argentina

Buenos Aires 793

Chile

Santiago 506
XXXIX

Peru

Huancayo 64, 107, 128, 288, 1140, 1321

Talara 288

C. OCEANS, SEAS AND ISLANDS

Antarctic regions

Antarctic 140, 369

AdelieLand 130, 131

HalleyBay 157

Marie Byrd Base 324

Statatian Vostak (U. S. S. R. ) 763

Syowa Base (Japan) 913

Falkland Islands 1153, 1201

Arctic Region 1112, 1114

Arctic Ocean

Station SP-3: 382

Canadian Arctic 1098

Soviet Arctic

Franz Joseph Land

Tikaia Bay 81

Atlantic Ocean

North Atlantic 168

Azores

Terceire Island 706

Bermuda 1201

Iceland

Keflavik 423

Mediterranean Region 1034

Mediterranean Sea

Malta 245, 423

Pacific Ocean

North Pacific 227, 1119

South Pacific 1242

Mariana Islands 227
xl

South Pacific (cont'd.

)

Cook Islands

Raratonga 140, 517

Macquaria Islands 252, 253, 309, 769, 794, 795,

1238

Pitcairn Island 140

Tropical Pacific 819

Campbell Island 140

Johnson Island 1242

Kermadec Islands

Raoul 140

Western Pacific

Fiji Islands 140, 1328, 1330

Hawaiian Islands 20, 227, 285, 1028, 1137

Apia 819, 1242

Maui 819

Ryukyu Islands

Okinawa 134, 1159
BIBLIOGRAPHY ON IONOSPHERIC PROPAGATION

A-l Abbot, Charles G. (Smithsonian Inst. ), Periodicities in ion- ospheric data. Smithsonian Miscellaneous Collections, 35

(10), May 28, 1958. 5 p. fig., 3 tables. DWB (M10. 35

A126pe).

A-2 Abbott, W. N. , Quelgues interessantes variations du souffle de fond observees sur les frequences de 17. 6 Mc/s . (Some interesting variations of static noise at frequencies

of 17. 6 Mc/s. ) Journal of Atmospheric and Terrestrial Physics, ll(l):72-74, 1957. fig., ref. English summary p. 72.

DWB—Observations of static on 17. 6 Mc/s at St. Omer at

2 hr intervals (1 hr before, 1 and 3 hrs after sunset) show a

slight decrease (0. 6 dB) after sunset in winter and spring.

This disappears in July to Sept. when the presence of the

center of the Galaxy counterbalances loss of reception cone.

It is attributed to descent of F layer. On 5 Mc the effect is

opposite. --C. E. P. B.

A-3 Abel, W. G. and Edwards, L. C. , Source of long-distance

backscatter. Institute of Radio Engineers, Proceedings,

39(12): 1528-1541, 1951. -Study of scattering of electromagnetic radiation which occurs when it encounters irregularities along path of propagation; conflicting opinion in ionospheric physics as to whether backscatter has origin in

E region of ionosphere or at surface of earth; method of

determining source of long distance backscatter; results

obtained using this method at frequencies of 9, 12, 16 and

22 Mc. »E. I. S.

A-4 Abel, William, Use of long-distance backscatter to deter- mine skip distance and maximum usable frequency. International Scientific Radio Union-Institute of Radio Engineers,

Joint Meeting held Washington, D. C. , April 1951,
Measurements of delay time in the 5- to 30-mc band between

the leading edge of the backscatter pattern and the response

of a beacon transponder has shown that delay time to the

leading edge of the backscatter is a measure of the skip distance. Since the frequency on which backscatter is obtained

is the maximum usable frequency (muf) for the skip distance

of this frequency, the muf for other distances can be obtained

by conventional methods. Backscatter can be obtained using

peak-power outputs as low as 200 - 300 w. Methods are being developed to permit instantaneous determination of skip

distance using ordinary transmitters and receivers together

with suitable display equipment.

A-5 Aden, Arthur L. , de Bettencourt, J. T. and Waterman, A. T.

,

Jr. , Note on ionospheric radio wave polarization. Journal of

Geophysical Research, 55(l):53-56, March 1950. —In magnetoionic theory, certain misleading or incorrect statements re- garding polarization of ionospheric radio waves have appeared;

notion that ordinary and extraordinary slips es should have mutually perpendicular major axes is not, in general, correct, being applicable only in case in which collisional friction of

electrons is neglected. --E. I. S.

A-6 Agranovich, V. M. and Rukhadze, A. A., ( On the propaga- tion of electromagnetic waves in a medium with appreciable

spatial dispersion. ) Zhurnal Eksperimental 'noi i Teoreticheskoi Fiziki, 35(4): 982-984, 1958. In Russian. Transl. into

English in Soviet Physics JETP, N. Y. , 35(i. e. 8) No. 4:685-

686. 5 refs. , 12 eqs.

A-7 Agy, Vaughn, Bibliography of Arctic ionospheric research in

the United States and Alaska since 1949. U. S. National

Bureau of Standards, NBS Report, No. 5561, March 7, 1958.

11 p. refs. Reproduced from typescript. DWB--The available

unclassified material on Arctic ionospheric propagation of

1-30 Mc/s radio waves, including magnetic and auroral activities, is listed as follows: a) Papers in the literature, 23

items; b) Reports by private organizations, 50 items; c) Report of work by U. S. Government agencies, 15 items. Informative notes on the respective research programs and contracts

listed are included. --W. N.

A-8 Agy, Vaughn, Motion of the storm-D regions . Nature, London,

173(4401) :445-446, March 6, 1954. 3 figs. , 3 refs. DWB--

Variation of black-out due to excessive absorption is shown

by charts of average probability, its amplitude, and time of

maximum. No indication of a 48 hr rotation was found.

--C. E. P. B.
A-9 Agy, Vaughn (Natl. Bu. of Standards, Boulder, Colo. ), Results of ionospheric drift measurements in the United

States. (In: Polar Atmosphere Symposium, Oslo, July 2-8,

1956, Proceedings, Pt. 2, Ionosphere Section. N. Y. Pergamon Press, 1958. p. 23-25. 2 figs. ) DWB Also issued

in: Journal of Atmospheric and Terrestrial Physics, London,

Special Supplement, Pt. 2, 1957, pub. 1958. p. 23-25. 2

figs. DLC--The Bureau of Standards suspended its work on

drift measurements for about 2 years but with the help of

similar reports from Ottawa, Canada and Cambridge, Eng.

,

a summary has been made for the polar plot of daytime Eregion winds covering the years July 1950-June 1953. The

result shows that the wind vector blows away from the

origin of the charts; that during the winter there is a pronounced clockwise rotation in the phase of the wind and

direction of the average wind changes through the year.

The data were taken near Wash. , D. C. But some recent

work has been done at Puerto Rico by using two frequencies, 2. 33 Mc/s and 4. 57 Mc/s, and determining the

effects of the correlation method with that of similar fades.

--N. N.

A-10 Agy, Vaughn and Davies, Kenneth, Ionospheric investigations using the sweep-frequency pulse technique at oblique

incidence. U. S. National Bureau of Standards, Journal of

Research, Sec. D, 63(2): 151-174, Sept. /Oct. 1959. 26

figs. , table, 24 refs. DWB, DLC—This paper describes the

present state of oblique-incidence investigations of the ionosphere, using the sweep-frequency pulse technique, with

special reference to the work carried out at the National

Bureau of Standards. After a short review of the published

literature, oblique -incidence sweeps are presented showing

the diurnal and seasonal variations on two east-west paths

of lengths 1, 150 kilometers and 2, 370 kilometers. The discrepancies between observed and calculated maximum usable

frequencies are presented for both paths and then various

phenomena of interest are shown. Finally, the above phenomena are discussed in the light of existing knowledge and

theory and, in particular, it is shown that the discrepancies between observed and calculated maximum usable frequencies are unlikely to be caused by magnetoionic deviation of the ray. --Authors' abstract.

A-ll Aikin, A. C. , A tabulation of group height, phase height

and nondeviating region absorption at various low frequencies

for a number of models of the lower ionosphere. Pennsylvania

State Univ. Ionosphere Research Laboratory, Contract AF

19(604)-1304, Scientific Report No. 101, March 1, 1958. 88 p.

4 figs. , 5 tables, 9 refs. , Oct. 29, 9 eqs. numerous graphs.

DWB (M10. 535 P415i)--
Methods for obtaining group height, phase height and nondeviative absorption are outlined. These methods are then

applied to fifty reasonab le electron density profiles. Tables

of the resulting group and phase heights and non-deviative

absorption are given for frequencies of 75 kc/sec, 150 kc/sec,

300 kc/sec and 500 kc/sec. The application of the models to

sunrise effects is discussed. -•Author's abstract.

A-12 Aitchison, G. J. (Dept. of Physics, Univ. of Adelaide),

Ionospheric demodulation of radio waves at vertical incidence. Australian Journal of Physics, Melbourne, 10(1): 204-207, March

1957. 2 figs., 3 refs., 2 eqs. DLC--In a previous communication, Aitchison and Goodwin (1955) have described an investigation carried out at the University of Adelaide on the demodulation of radio waves at vertical incidence. At a frequency of

1550 kc/s, which is close to the local gyro frequency of approximately 1600 kc/s at the height of the E layer of the ionosphere, marked reductions in the modulation depth were observed on the sky wave. The experimental results tabulated

in the previous communication suggested that the effect was

greatest at a modulation frequency of the order of 800-1500

kc/s. From subsequent measurements it is apparent that, in

the case of F-layer reflection, the demodulation was greatest

at a modulation frequency of, very approximately, 1 kc/s; in

the case of E-layer reflection, the degree of demodulation

did not vary markedly with change of modulation frequency.

—Author's abstract.

A-13 Akasofu, Syun-ichi, (Geophysical Inst. , Tohoku Univ.

,

Sendai, Japan), Magneto-hydrodynamic waves in the ionosphere. Journal of Atmospheric and Terrestrial Physics, London,

15(1/2): 156-160, Sept. 1959. 2 figs. , 12 refs., 6 eqs. DLC--

The study is made of the magneto-hydrodynamic waves in the

ionosphere and the outer atmosphere. The dispersion relations

of Alfven waves are obtained and it is shown that various

types of geomagnetic micropulsations and ionospheric noises

appear in the wide range from audio- to very low-frequency.

The Alfven waves with finite amplitude are also studied. It is suggested that the retarded sound-type shock wave may be

identified with the descending "cusps" on h'-f curve of ionogram. --Author's abstract.

A-14 Albrecht, Hans J. , Investigations on great-circle propagation

between eastern Australia and western Europe. Geofisica Pura

E Applicata 38:169-180, 1957. 2 figs., 2 tables, 25 refs.

English and German summaries. --
From propagation data in the frequency range 3-30 Mc/s collected during the period 1952 to Feb. 1957, the author selected the results representative of conditions prevailing

during the sunspot minimum, Nov. , 1953 to Dec. , 1954. The

emphasis being laid on studies concerning propagation near

the LUHF, monthly median values of path attenuation, path

characteristics, and times of openings are given where the

measurements were sufficiently conclusive. All results are discussed with reference to ionospheric predictions.

A-15 Albrecht, Hans J. , On instrument effects in ionosphere data.

Journal of Atmospheric and Terrestrial Physics, 13(1/2): 173-175,

Dec. 1958. 2 refs. , 3 eqs.

A-16 Albrecht, Hans J. (Schramberg-Sulgen), Further studies on

the chordal-hop theory of ionospheric long-range propagation.

Archiv fur Meteorologie, Geophysik und Bioklimatologie,

Ser. A, Vienna, ll(l):84-92, 1959. fig,, 4 tables, 9 refs.,

5 eqs. German and French summaries p. 84. DWB, DLC--

This paper presents new results of the author's investigations

on ionospheric propagation in Australia from 1952 to 1957.

Considerations on path attenuation are followed by a discussion on the propagation paths to North America and Western

Europe, Conclusions are in agreement with the author's

previous publications in this field. --Author's abstract.

A-17 Albrecht, Hans J. (Schramberg-Sulgen), Technische Gesichtspunkte bei Ionospha'rendatenauswertung und modernem Ionosondenaufbau. (Technical approach to ionospheric data

evaluation and modern ion-sonde construction. ) Archiv fur

Meteorologie, Geophysik und Bioklimatologie, Ser. A, Vienna,

11(3):383-391, 1959. 3 figs. , 10 refs. , eqs. German, English

and French summaries, p. 383. DWB, DLC--Using his previous investigations on instrument effects with ionosphere

measurements the author deals, in the present paper, with

an extension of the theoretical adaptation method. With re- ference to those results, the modern equipment of ionosphere

stations is discussed. --Author's summary.

A-18 Alekseev, P. P. et al., Raketnye issledovaniia atmosfery. (Rocket studies of the atmosphere. ) Meteorologiia i Gidrologiia, Leningrad, 8:3-13, 1957. 6 figs. (incl. photos and diagram), table, refs. , 8 eqs. DLC. Trans, into English by

M. I. Weinreich. Available Sandia Corporation, Albuquerque,

N. Mex. DWB (M10 A366ro)--The disposition of meteorological apparatus in the cone of a meteorological rocket, the type

of apparatus, the electrical power, etc. are described in detail

with the aid of a diagram. The launching of the meteorological

rocket and the communication system involved in the reception
of signals from the rocket are discussed. Equations are presented showing: (1) the relationship between the fundamental

parameters of the radio-telemetric line, (2) the relationship

between pressure within the manometer and pressure in the

free atmosphere, and (3) the relationship between the temperature of the thermometer and the temperature of the ambient

atmosphere. The computation of the terms of the equations

and their validity with reference to the apparatus employed

are illustrated. A graph and table showing the distribution

of pressure, temperature and density with height as obtained

from rocket measurements are presented. --I. L. D.

A-19 Allcock, G. Mck. , Ionospheric absorption at vertical and

oblique incidence. Institution of Electrical Engineers, London, Proceedings, Pt. 3, 101(74): 360-367, Nov. 1954. 11

figs. , table, 24 refs. , 15 eqs. Discussion on the above paper. and (on) two other papers on the ionospheric absorption and re - flection of radio waves, before the Radio Section, 5th May,

1954. Ibid. , p. 367-370. Authors' replies to the above discussion. Ibid. , p. 370. DLC --Measurements of the ionospheric absorption of radio waves of frequency 9. 15 Mc/s over an

800-km path, and of frequency 5. 455 Mc/s at vertical incidence at the mid-point of this path, have been made simultaneously over a period of 14 months. A discrepancy between the

observed results and those predicted by Martyn's absorption

theorem is found, which varies diurnally. The oblique-incidence results are examined in detail, and empirical formulas

for diurnal and seasonal variation of absorption are derived.

--Author's abstract.

A-20 Allcock, G. McK. , The prediction of maximum usable frequencies for radiocommunication over a trans equatorial path. Institution of Electrical Engineers, London, Proceedings, Pt.

B, 103(10): 547-552, July 1956. 3 figs. , table, 12 refs. DLC

--Observations of transmission on 15 Mc/s from Hawaii re- ceived in New Zealand (great circle path 7500 km) in 1950.

54 were compared with British, American and Australian methods of predicting m. u. f. and with calculations directly from

h'f data in the S. Pacific. The predictions were 4-7 Mc/s too

high. Predictions assuming 3 equal length hops were generally too low by 1-2 Mc/s, the discrepancy being attributed to

the presence of a sporadic E region. --C. E. P. B.

A-21 Allcock, G. McK. (Dominion Physical Lab. , Lower Hutt,

New Zealand), The electron density distribution in the outer

ionosphere derived from whistler data. Journal of Atmospheric

and Terrestrial Physics, New York, 14(3/4): 185-189, June

1959. 8 figs. , table, 13 refs. , 21 eqs. DWB, DLC--
A method, using successive approximations, is given for

finding the variation of electron density N with height h in

the outer ionosphere, when the variation of whistler dispersion with geomagnetic latitude is already known. From the

application of the method to specific whistler data, it is

inferred that the electron density distribution in the outer

ionosphere decreases exponentially with height at least in

the height range 1000 to 13, 000 km, and that during the period January to May 1957 the equation describing the distribution within this height range was: N 5. 75 X 10^* exp

(-h/2640) where N is in cm"3 and h in km. --Author's abstract.

A-22 Al'pert, la. L. , Rasprostranenie radiovoln. Spetsializirovannyi biblioqraficheskii spravochnik. (Radio wave propagation. Specialized bibliographic reference book. ) Moscow,

Izdatel'stvo Akademii Nauk SSSR, 1949. 195 p. At head

t-p: Akademiia Nauk SSSR, Otdelenie Fiziko -Matematicheskikh Nauk. DLC --Fifty books are arranged chronologically

by imprint and over 1500 articles from periodicals are ar- ranged under the following main headings: I. Propagation of

radio waves over the earth's surface (291 refs. ), II. Propagation of radio waves in the ionosphere (875 refs. ), III. Propagation of the "celestial" ray (199 refs. ), IV. Propagation

of ultrashort waves (93 refs. ), V. Propagation of radio waves

in the troposphere (57 refs. ) and VI. Investigation on sferics

(99 refs.). In some cases, a section is subdivided. References are arranged chronologically within a section (or subsection). Included are a list of 75 periodicals arranged by

country (Russian, England, U. S. , France, Germany, Italy,

Japan, Australia, India and Canada) with abbreviation and

an author index alphabetically arranged. All titles are in

the original language. Imprints cover the period from 1878 - 1948. --M.L. R.

A-23 Al'pert, la. L. , Statisticheskii kharakter struktury ionos - fery. (Statistical nature of the ionospheric structure.)

Uspekhi Fizicheskikh Nauk, Moscow, 44(1):49-91, Jan. 1953.

18 figs. , 3 tables, 25 refs. , 104 eqs. DLC--An extensive

"survey article" reviewing in logical sequence the characteristics of the ionosphere as determined through statistical

analysis of radio propagation data. The various layers of

the ionosphere from which reflections occur during quiet

periods are shown to be connected with the primary, secondary and tertiary reflections of signals (beautifully illustrated by a recorder record). The diffuse, complex and disturbed nature of the ionospheric layers at certain times makes

a complicated statistical study necessary to formulate a theory or model of the ionospheric structure and behavior.

The measurement of ionospheric drift is taken up in the final
8

paragraph. The author shows a good knowledge of the literature both native and foreign (3/5 of the references cited

are from foreign sources). --M. R.

A-24 Al'pert, la. L. ; Ginzburg, V. L. and Feinberg, E. L.

,

Rasprostranenie radiovoln. (Radiowave propagation. ) Moscow, Gos. Izdat. Tekhniko-Teoreticheskoi Literatury, 1953.

883 p. 128 figs. , 124 tables, 373 refs. DLC--The most advanced text on theoretical and empirical aspects of radio

wave propagation in all bands from microwaves to long waves,

and in the troposphere and ionosphere. First there is a historical sketch of progress in radio science since POPOV

(1895), especially in Russia. Then in Pt. I, the general

theory of radio propagation; Pt. II, theory of propagation in

ionosphere (p. 278-546); Pt. Ill, structure of ionosphere and

experimental data on formation; regular and irregular processes in ionosphere (p. 547-680); Pt. IV, experimental investigations on propagation and comparison with calculated data

by various methods (p. 681-870). The first part of this voluminous text is mainly theory; the last part is practical —

data, tables, recorder records and interpretations, nomograms,

etc. All of the layers of the ionosphere are treated, as well

as the troposphere in relation to long distance propagation.

Radar and impulse propagation are also considered. The ex- tensive bibliography in 5 parts consists of about half Russian

and half foreign literature through 1952. --M. R.

A-25 Al'p©rt, la. L. and Borodina, S. V., Issledovanie rasprostraneniia dlinnykh i sverkhdlinnykhradiovoln metodom analiza

form atmosferikov. (Analysis of the distribution of long and

very long radio waves by means of analysis of the wave form

of atmospherics. ) Radiotekhnika i Elektronika, Moscow,

l(3):293-305, 1956. 10 figs. , tables, 20 refs. , 25 eqs. DLC

(Slavic, Deck 8)--A method for obtaining data on the propagation of low frequency electromagnetic waves on the basis

of a complete harmonic analysis of photo-oscillograms of

individual atmospherics, excited by thunderstorm discharges,

is described. The experimental installation, results of its

testing, and of some measurements are briefly described.

Common characteristics of atmospheric configurations, and

results of analysis of one of their types are presented. It is shown that the data on the dependence of the field's re- lative amplitude, and of the average velocity — on the frequency and on distance — are, on the whole, in good agreement with the results of theoretical calculations. --Authors'

abstract. '
A-26 Al'pert, la. L. , Kratkii ocherk sovremnnykh predstavlenii

o rasprostranenii radiovoln v ionosfere. (A short sketch of

present ideas on the propagation of radio waves in the ionosphere. ) Akademiia Nauk SSSR, Izvestiia, Ser. Geofiz.

,

No. 11:1418-1430, 1957. 56 refs. DWB--After a brief review

of the history of our knowledge of the propagation of radio

waves, the author summarizes our present knowledge on the

ionospheric propagation of radio waves and, in particular,

Soviet contributions to this knowledge. A review of the var- ious studies on the influence of the earth's surface on the

distribution of radio waves includes the work of V. A. Fok

on the change in the velocity of radio waves with distance,

the effects of a plane and spherical earth upon the propagation

of radio waves, the influence of the earth's surface on the propagation of long radio waves, the "washing out" and dispersion of the conductive layer of the ionosphere, etc. The discussion of the relationship between the ionosphere and radio

waves includes an account of the structure of the ionosphere

(electron concentration, etc. ), reflections of radio waves in

the ionosphere, extinction of waves and plasma as a function

of the field charge of incident waves, etc. --I. L.D.

A-27 Al'pert, la. L. , Electron density fluctuations and the scattering of radio waves in the ionosphere. Soviet Physics JETP,

New York, 6(1): 167-175, Jan. 1958. Trans, by I. Emin of

original Russian Fluktuatsii elektronnoi plotnosti i rasseianie radiovoln v ionosfere, in Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki, 33(1): 213-224, July 1957. 7 figs.

,

12 refs. , 27 eqs. Also: Proshkin, E. G. and Kashcheev,

B. L. , On the question of the fluctuations of electron concentration in the F-layer of the ionosphere. Soviet Physics

JETP, 6(4):818-819, April 1958. Transl. by H. Zirin of original Russian, K voprosu o fluktuatsiiakh elektronnoi kontsentratsii v F-sloe ionosfery, in Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki, 33(4):1062, Oct. 1957. figs., 2 refs.

DLC--A description is given of results from a determination

of electron density fluctuations obtained by measuring the

"turbidity coefficient" of the ionosphere and energy scattered at very high frequencies. The linear dimensions § of

inhomogeneities at ^80 km, which are effective in UHF

scattering, were also determined. The formulas employed

were based on an expression for the scattering cross section cr which was obtained with the autocorrelation coefficient p(r) r^ exp — r/ f

)2 . The author concludes that

when the ionosphere is sounded at frequencies below the

critical frequency, the received signal comprises, in addition to the "specularly" reflected wave, waves which are principally scattered forward and partly reflected at higher
10

ionospheric levels. In oblique distant UHF transmission

through the ionosphere, scattering from inhomogeneities of

optimum size makes the largest contribution. Proshkin and

Kashcheev report an application of Al'pert's formula to the

calculation of the distribution of F layer electron density

inhomogeneities effective in ordinary wave scattering (Kharkov, 1955-1956; diagram) and find no altitude dependence of

electron density fluctuations. --G. T.

A-28 Al'pert, la. L. , Ionosfera i iskusstvennve sputniki Zemli.

(The ionosphere and artificial earth satellites. ) Priroda,

Moscow, No. 10:71-77, Oct. 1958. 3 figs. DLC--The author

discusses the pre-sputnik knowledge on the concentration and

density of electrons above the earth and the importance of

more precise data on the distribution of electrons with altitude above 100 km, the effective frequency of collisions of

electrons with other heavier gas particles, and the small

scale inhomogeneities in the atmosphere. The possible origins of these inhomogeneities, which are characterized by

fluctuations of electron concentration, are considered,

namely; ionospheric turbulence and longitudinal plasma

waves. The special problems arising in the use of satellites to study the atmosphere are considered. These result

from the use of radio signals to measure various parameters

and the complexity of effects occurring in the vicinity of the

satellite. The applications of the coherent Doppler method

and of the method of observation based upon radio "rise"

and "set" are discussed. --I. L. D.

A-29 Al'pert, la. L. , Sostoianie vneshnei ionosfery. (The state

of the outer ionosphere. ) Priroda, Moscow, No. 6:86-87,

June 1958. table, 3 foot-refs. DLC--Trans. into English

by E. R. Hope issued as Canada. Defence Research Board,

Translation T-304-R, Sept. 1958. DWB--The method of radio

observations on the first earth satellite is described briefly

and the results of such observations at 6 points during Oct.

5, 6 and 7, 1957 are summarized. The electron concentration in the outer ionosphere diminished with altitude considerably more slowly than it increased in its lower portion.

A table is presented giving the electron concentration N/cm^

up to 3100 km and also the density of neutral particles per

cm^ up to the same height. The computation of the density

of the latter is described. At dis tances of 2000-3000 km

from the earth, the electron concentration is close to 10^ —

102 electrons/cm^ and the density of neutral particles is of

the order of 1 per/cm^. Hence the atmosphere approaches

the properties of interplanetary gas at 2000-3000 km. The

agreement between the data on the outer atmosphere obtained

by means of rockets and lunar signals is compared with those

obtained with the artificial earth satellite. --I. L. D.
11

A-30 Al'pert, la. L. ; Chudesenko, E. F. and Shapiro, B. S. , Rezultaty issledovarmiia vneshnei oblasti ionosfery po nabliudeniiam za radios iqnal ami pervoqo iskusstvennogo sputnika

Zemli. (Results of research on the outer region of the ionosphere from observations of the radio signals of Sputnik I. ) Akademiia Nauk SSSR. Mezhduvedomstvennyi Komitet po

Provedeniiu MGG, Predvaritel'nye itogi nauchnykh issledovanii. . . Sputnikov Zemli i raket, No. 1:40-108, 1958. 18 figs.

26 tables, 15 refs. , 28 eqs. English summary, p. 51. DWB

--The method of research on the upper atmosphere by means

of artificial earth satellites described in this paper is based

upon the determination of the time of "radios et" and "radiorise" of the satellite. The distribution of the concentration

of electrons in the outer ionosphere provides information

about the properties of interplanetary gases. The trajectories of radiowaves in the ionosphere and methods of investigating them are described in detail. Results of the

theoretical calculations of the maximum horizontal distance

of the receipt of radio signals are given. The calculations

were made for a spherical earth and the tabulation of the

resulting elliptical integrals was carried out with a high

speed electronic computer. The calculations used the parabolic model of the lower ionosphere and the exponential decrease of the electron concentration in its outer part. In

the analysis of the experimental data the parameters of the

lower ionosphere and the altitude of the artificial satellite

. were used and the maximum distances of signal reception

were determined on the basis of ballistic data and other

studies of the trajectories of the satellite. The electron

concentration of the ionosphere N was found to decrease

much slower after its maximum Km- For the model N| -?y ~^~ Kjno ~e " * y the value X —3. 5 10"3 1/km is obtained.

This means that the number of electrons in the outer part

of the ionosphere is approximately 3. 6 more than in the lower

part. Extropolation of the observational data received for the

altitudes y300 650 - 700 km to y ^3000 shows that with

Y~ 2000 - 3000 km N^ 200 - 300 el/cm3. A curve of the

density of neutral particles n(^) according to the life time

of the electron and the time between different acts of ionization is drawn. It is concluded that the altitude of the "limits"

of the atmosphere (region of contact with interplanetary space)

is of the order of 2000 - 3000 km. Appendices contain the following: calculation of the maximum distance of distribution of

waves in the approximation of geometrical optics and tables

of maximum horizontal distance rm (in km) for a series of

given parameters. --Authors' abstract and I. L. D.
12

A-31 (American Radio Relay League), Study of trans equatorial

scatter propagation. Contract AF 19(604) -2171, Final Report,

1959. 25 p. At head of title: IGY project 6. 22. -To collect

and utilize observations by amateur radio operators in the

very high frequency range the APRL-IGY Propagation Research

Project was organized. The present paper is a systematic re- port of how the project was carried out. It discusses in separate chapters the actual nature of the project, setting up the

observing group, data processing, data codes, and finally,

the results. It is reported that 593 amateurs out of 1320 on

the project mailing list, actually submitted the semi-monthly

logs requested. Bands available to them are one or more of

the following (depending on location): 50-54, 70-72, 144-148,

220-225 and 420-450 mo. The data received was duly processed. The projects results consist of 281, 640 punched

cards with the following v. 1. f. (chiefly 50 Mc) propagation

modes, auroral reflection, F2-layer back scatter, sporadic

E single and double hop, meteor/ionospheric forward scatter

and trans equatorial scatter. Upon analysis it is found that

trans equatorial scatter is not limited to the Americas but

occurs in many parts of the world, all paths being roughly

symmetrical to the geomagnetic equator. --I. S.

A-32 Anderson, A. D. and Hoehne, W. E. , Experiments using

window to measure high-altitude winds. U. S. Naval Research

Laboratory, NRL Report, No. 4682, Jan. 10, 1956. 9 p. 8

figs. , 2 tables, chart, 4 refs. DLC—Strips of metal foil (window), dispersed by balloon and aircraft, have been tracked by

radar to measure wind velocities at altitudes up to 74, 000 ft. These wind velocities have been compared with those measured over the same altitude range by GMD-1A equipment and

radar -target tracking. The results indicate promise for obtaining high-altitude winds by this new technique. Further

experiments envisioned for the altitude range from 100, 000

to 200, 000 ft will necessitate the use of rockets to carry and

eject the window. --Authors' abstract.

A-33 Aono, Yuchiro (Radio Research Laboratories, Tokyo), Regional anomalies in foF2 of the ionosphere. Japan. Science

Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, l(l):30-33, 1953. 3 figs. Also in:

International Council of Scientific Unions. Mixed Commission

on the Ionosphere, Canberra, Australia, Aug. 24-26, 1952,

Proceedings, pub. 1953. p. 167-173. fig. , 2 refs. DWB--

Charts of the regional anomalies in foF2 of ionosphere for Jan.

,

March and May, for the entire world are presented and are based on ionospheric data from all over the world for four years

(1946-50 excluding 1949). Monthly charts were drawn and the

3 presented to show winter and summer conditions. Anomalies
13

are represented as to ratio of average monthly value to highest

monthly median value, expressed in percentages, with lines

drawn for each 10%. Anomalies are analyzed and discussed.

--M. R.

A-34 Appleton, Sir Edward, Geophysical influences on the transmission of wireless waves. Physical Society of London, Proceedings, 37(2):16-22, Feb. 15, 1925. -An early general discussion of the ionosphere.

A-35 Appleton, Edward V. and Barnett, M. A. F. , On some direct

evidence for downward atmospheric reflection of electric rays.

Royal Society of London, Proceedings, Ser. A, 109(752):621-

641, Dec. 1925. 8 figs. , foot-refs. , 7 eqs. DLC--Refers

briefly to unsuccessful attempts of Smith-Rose and Barfield

to find evidence for the existence of the Heaviside layer.

Authors then describe two sets of experiments carried out

at the Cavendish Laboratory, Cambridge, in which they compared intensities of fading of signals from London and Birmingham. These experiments were the first direct evidence of the

existence of the Kennely -Heaviside layer. Conclusions

reached were: 1) atmospheric rays are elliptically polarized,

2) the reflection coefficient of the ionized layer is between

0. 2 and 6% and 3) in inferior limit for the number of electrons

per cc in the ionized layer is 105. --M.L. R.

A-36 Appleton, Sir Edward and Barnett, M. A. F. , On wireless

interference phenomena between ground waves and waves deviated by the upper atmosphere. Royal Society of London,

Proceedings, Ser. A, 113:450-458, 1926. -Using 340-400

meter waves studied interference between ground and sky

waves. Study equivalent height.

A-37 Appleton, Sir Edward, The influence of the earth's magnetic

field on wireless transmission. International Scientific Radio

Union, Recueil de Travaux de l'Assemblee General (Papers),

Vol. 1, 1927 (paging not given).

A-38 Appleton, Sir Edward, The existence of more than one ionized

layer in the upper atmosphere. International Scientific Radio

Union, Recueil de Travaux de l'Assemblee General (Papers of

the General Assembly), Vol. 1, 1927 (paging not given). -- Finds just before morning on a fixed frequency that the height

of reflection increases.

A-39 Appleton, Sir Edward and Ratcliffe, J. A. , On a method of determining the state of polarization of downcominq wireless

waves. Royal Society of London, Proceedings, Ser. A, 117:

516-588, 1928. --Describe method for polarization measurements.
14

Find waves elliptic ally polarized, with usually left-hand

sense. Suggest measurements in the southern hemisphere.

A-40 Appleton, Sir Edward, The equivalent heights of the atmos - pheric ionized regions in England and America. Nature,

London, 123:445, March 23, 1929. --Notes American observation of virtual height, as well as the English, can be explained in terms of two layers.

A-41 Appleton, Sir Edward, Polarization of downcoming wireless

waves in the southern hemisphere. Nature, London, 128:1037,

Dec. 19, 1931. —States that A. L. Green went to Australia and

made polarization measurements on waves propagated in the

direction of the magnetic field, and observed the component

with least absorption to have right hand polarization. Measurements by Appleton in England, with Green's assistance,

showed left hand polarization. Check for magneto-ionic

theory and explanation of direction finding errors. A-42 Appleton, Sir Edward and Builder, G. , Wireless echoes of

short delay. Physical Society of London, Proceedings, 44(1):

76-87, Jan. 1, 1932. --Built a group retardation recorder using

pulses, and compare with frequency change equipment. List

relative advantages.

A-43 Appleton, Sir Edward, On two methods of ionospheric investi- gation. Physical Society of London, Proceedings, 45(5):673-

688, Sept. 1, 1933. --Interprets P'-f (virtual height versus frequency) data. Finds double refraction in E region and concludes E region is electronic. Finds Fl region in the daytime.

Rate of decay of F region ionization was measured, and found

not to be explicable in terms of a simple recombination law

between ions and electrons. Measured rate of F-ion production at sunrise.

A-44 Appleton, Sir Edward and Builder, G. , The ionosphere as a double refracting medium. Physical Society of London, Proceedings, 45, Pt. 2, No. 247:208-220, March 1, 1933. -- Verify that splitting of echo traces is due to magneto-ionic

effects by checking polarization. Describe the conditions

under which the refractive index becomes zero. Point out dependence of transmission type on 2pTjV/p'p2/ and state that

for quasi -transverse propagation the separation of

fp and fp is (f^ - i^) - (fjjf

1 >/(f| + l~). For a quasi -longitudinal transmission, however, f. - f = f„. Compute limiting

polarizations and find them nearly circular. Say extraordinary
15

wave is nearly circularly polarized throughout its path,

while ordinary component is changed to linearly polarized

at point of reflection, hence there are internal reflections

along route, and ordinary echo is not as clear as extraordinary echo.

A-45 Appleton, Sir Edward, Fine-structure of the ionosphere.

Nature, London, 131:872-873, June 17, 1933. -Discusses re- sults of Schaefer and Goodall, and speaks of notation of E2

region, of which the maximum occurs between E and F 1.

A-46 Appleton, Sir Edward, Radio observations during international

Polar Year 1932-33. Royal Institute of Great Britain, Weekly

Evening Meetings, Oct. 27, 1945.

A-47 Appleton, Edward; Naismith, R. and Builder, G. , Ionospheric

investigations in high latitudes. Nature, London, 132(3330):

340-341, Aug. 26, 1933. DLC--Wireless observations were

made during 1932-33 at Troms^, Norway (lat 69°39. 8'W, long

18 56. 9'E) on wavelengths 500 to 20 metres. Absence of

echo on all wavelengths is caused by absorption-limitation

due to production of ionization at abnormally low levels.

It is concluded that the ionizing agency that causes magnetic

storms can produce ionization at levels below ultraviolet

light produced ionization. Difficulties in radio communication

on the polar cap are due to absence of reflection from the ionosphere which is associated with conditions of magnetic activity.

A-48 Appleton, Sir Edward, A method of measuring the collisional

frequency of electrons in the ionosphere. Nature, London,

135:618-619, April 20, 1935. -States log P = -(v/2c) • (P* - P)

where v is the collisional frequency, P' is group path, P is

the optical path. Writes

fj log P, - i2log P

2

= ^L f2

(P^ - P

2

) - £, (PJ - Pj)

and since c

P

2

f2 PA

=

fl S

p'df

he gets

v = fj log Pj - f2

log P

2

2c area X

(In differential notation, this can be written)

V

2c

& (* log P)

<§p'
16

A-49 Appleton, Sir Edward and Chapman, Sydney, Report on ionization changes during a solar eclipse. Institute of Radio

Engineers, Proceedings, 23(6): 658-669, June 1935. --Indicate

that the time of eclipse should indicate velocity of ionizing

agency. Quote conclusions of all observers of eclipse. The

existence of a corpuscular eclipse was not proved.

A-50 Appleton, Sir Edward and Ingram, L. J. , Magnetic storms

and upper-atmospheric ionization. Nature, London, 136:548-

549, Oct. 5, 1935. --Observed F2 maximum ionization at midnight, and correlated with magnetic activity. Found correlation coefficient of -0. 247. Wonder if cause is expansion of

F2-layer due to heating by storm producing agent.

A-51 Appleton, Sir Edward and Boohariwalla, D. B. , The influence

of magnetic field on the high freguency conductivity of an ionized medium. Physical Society of London, Proceedings, 47(6):

1074-1084, 1935. --Experimentally vary pressure of air in a magnetic field and observe pressure for which RF conductivity is

maximum. Compares favorably with theory* Find collision

frequency proportional to pressure as expected. In absence

of H, conductivity was maximum at 16 cm wave length for

p = 0. 40 mm Hg; at 20 cm, 0. 32 mm; 28 cm, 0. 231 mm; 34 cm,

0. 19 mm; 80 cm, 0. 08 mm; etc.

A-52 Appleton, Sir Edward and Naismith, R. , Some further measurements of upper atmospheric ionization. Royal Society of

London, Proceedings, Ser. A, 150(871): 685-708, July 1935. -- Explain E and Fl seasonal changes in terms of variation of

ultra-violet light from sun. Believe difference in F2 may be

due to seasonal variations in molecular temperature. Think

T > 1200 K in summer. Consider recombination, attachment,

and ionization simply in relation to equilibrium electron density. Describe method of investigation in which carrier is

swept past receiver acceptance band. They think recombination in E-layer predominantly CCN^, since summer-winter ionization checks this assumption well.

A-53 Appleton, Sir Edward, Regularities and irregularities in the

ionosphere. Royal Society of London, Proceedings, Ser. A

162(911):451-479, Oct. 15, 1937. 10 figs. , 2 tables, 20

refs. , 30 eqs. DLC--In this lecture selected topics derived

from radio sounding in the ionosphere are discussed and considered in connection with results derived from a theory of

simple layer formation by solar ionizing radiation, travelling

rectilinearly and attenuated according to a mass -absorption

law. The presentation of the material includes three main

subjects discussed in detail in the following order: 1) Simple
17

region tormation. a. Height of maximum of ion-production;

b. height of under-boundary of layer of ion production; c. variation with height; d. total ion-production in a simple re- gion; e. total transverse conductivity of a simple region;

f. absorption of radio waves traversing a simple region.

2) Experimental results and discussion, a. The variation of

ionization with the sun's zenith distance; b. variation of absorption with the sun's zenith distance; c. the direct-current

conductivity of region E; d. the process of electron production

and decay; e. the actual height reached by radio waves and

the structure of the atmosphere. 3) Abnormalities.

From author's text.

A-54 Appleton, Sir Edward; Farmer, F. T. and Ratcliffe, J. A. , Magnetic double refraction of medium radio waves in the ionosphere. Nature, London, 141:409-410, March 5, 1938. Challenge paper of Martyn and Munro (NATR0138) as to interpretation of a rising trace below the gyro frequency. Claim curve

similar to ones in England which were found to be ordinary and

extraordinary components, with opposite polarization.

A-55 Appleton, Sir Edward; Naismith, R. and Ingram, L. J. , The

critical-frequency method of measuring upper-atmospheric ionization . Physical Society of London, Proceedings, 51(283) :81-

92, 1939. --Consider effects of layer thickness on group height,

echo-intensity, and frequency. Discuss the selection of critical frequencies from virtual height frequency data. Consider

abnormal E-region phenomena.

A-56 Appleton, Sir Edward and Naismith, R., Normal and abnormal

region-E ionization. Physical Society of London, Proceedings,

52(291) :402-415, May 1940. -Correlate normal and abnormal

E-layer phenomena with solar phenomena. The normal E-region

follows the sun and sunspots very closely. The abnormal Eregion has a tendency to follow the sunspots, but a number of

tendencies such as night occurrence seem hard to explain.

The corpuscular explanation requires particles capable of penetrating 1 cm of air at atmospheric pressure.

A-57 Appleton, Sir Edward and Beynon, W. J. G. , The application

of ionospheric data to radio communication problems. Physical

Society of London, Proceedings, 52(202): 518-533, July 1940. -- Consider plane earth oblique and normal incidence (P', f) re- lations. Find MUF and skip distance for flat and curved earth,

assuming mirror reflection (flat ionosphere). Compute MUF

factors for flat ionosphere; for maximum possible distance for

E-layer, f = 5.4 f while for F-layer a factor 3.5 is practical, max c Maximum single hop E-layer transmission is 2370 km. Compute

m^m^^^^^mm
18

frequency-angle-distance relation for parabolic layer and flat

earth, then obtain equivalent expressions for spherical geometry. Show that with curved ionosphere and parabolic distribution the propagation is quite similar to that with flat

earth if the critical frequency f is reduced to

f2 yTM 9

(1 - —5- — sin 1 ) G r* l O

f O

C

where r is radius to bottom of layer, y thickness of layer, o m

Give equations for finding MUF of parabolic layer for flat and

curved earth, and find a maximum error of 2. 5 percent in using

flat ionosphere curved earth formula.

A-58 Appleton, Sir Edward, A simple method of demonstrating the

circular polarization of ionospherically reflected radio waves.

Nature, London, 141:250, Feb. 27, 1943. -Describes method

of determining polarization using two loops at right angles.

If their output is beat with another signal, the phase difference in their outputs is maintained between the beats. The

other signal can often be the ground wave, the frequency

difference arising from Doppler effect due to lowering layer

height.

A-59 Appleton, Sir Edward, The scientific principles of radio loca - tion. Institution of Electrical Engineers, Journal, Pt. 1, 92

(57):340---, Sept. 1945. General survey, good. Mentions

that peculiar bursts occur on frequencies above the critical

and plots curve of relative frequency vs height, having maximum at E-layer level. States due to meteors. Also discusses

mathematically in appendix, the reflection and scattering of

waves from various shapes of metallic reflectors. Article

only partly ionospheric.

A-60 Appleton, Sir Edward, Two anomalies in the ionosphere.

Nature, London, 157(3995):691, May 25, 1946. 2 figs. DLC

--The variation of critical frequency with geographical latitude

and with magnetic dip of the F2 layer is discussed.

A-61 Appleton, Sir Edward and Beynon, W. J. G. , The application

of ionospheric data to radio communication problems, Pt. 2.

Physical Society of London, Proceedings, 59:58---, 1947. -- Graphs are given from which may be estimated the maximum

usable frequency of radio waves reflected by an ionospheric

layer in oblique incidence transmission. The curves based

on the theory given in Part I of the paper are drawn for such

ranges of layer thickness and layer height as are met with in

practice. The limitations in the accuracy and applicability
19

of the theory in practice are briefly discussed. Attention is

also drawn to the occurrence of abnormal transmission conditions under which long-distance communication via the ionosphere is possible on frequencies exceeding the normally

predicted values.

A-62 Appleton, Sir Edward, Geomagnetic control of F2 layer ioni- zation. Science, Wash., D. C. , 106(2740) : 17—, July 4,

1947. --It has been found that for constant longitude, the noon

values of ionization at numerically equal north and south latitudes are not equal. Also, there is a variation of noon ionization with longitude along a line of constant latitude. If equinox noon values of F 2 critical frequency are plotted ver- sus geomagnetic latitude, the above anomalies disappear. In

such a plot, higher values of ionization density are found as one approaches the geomagnetic equator, except for a trough

which exists within plus minus 18 degrees of the equator. The

reduced densities in the equatorial region are found to be associated with a bifurcation of the F-layer into Fl and F2 much

as in northern summer. A long term variation of F2 - layer

density with the sunspot cycle is found, with the ratio of maximum to minimum density depending upon season. The ratio

is two in the summer, four in the winter. The figures 4 and 2

given in the last paragraph of the letter are in error, and should be interchanged.

A-63 Appleton, Sir Edward; Beynon, W. J. G. and Piggott, W. R.

,

Anomalous effects in ionospheric absorption. Nature, London,

16(4103): 967-968, June 19, 1948. -Present results of oblique

incidence attenuation measurements which are inconsistent

with Martyn's equi-valence theorem. Identified source of additional attenuation as sporadic -E ionization. Path lengths

of 715 and 685 km.

A-64 Appleton, Sir Edward, Studies of the F2 layer in the ionosphere. Journal of Atmospheric and Terrestrial Physics, 1(2):

106-113, 1950. 6 figs. , table, 5 refs. MH-BH-Seasonal and

latitudinal variations in the height at noon of the F2 layer are analyzed and presented in diagrams. Washington, D. C. , and

Shibata; Trinidad and Huancayo and Wakkanoi, Palau and Christchurch data are compared month by month to show variations

at stations in the same latitude in the Northern Hemisphere,

at stations the same distance north and south of the equator

and at stations in the temperate and tropical zones, respectively. Relations between noon F2 layer height and magnetic

dip are compared for over 30 stations in Sept. 1944 (low sunspot activity) and for over 50 stations in Sept. 1948 (high sunspot activity). Change from the Northern Hemisphere type of

seasonal variation to the Southern Hemisphere type occur at

the magnetic equator not the geographical equator. —K. R.
20

A-65 Appleton, Sir Edward and Piggott, W. R. , World morphology

of ionospheric storms. Nature, London, 165(4187): 130-131, Jan.

28, 1950. --Find F2 layer critical frequencies at temperate zone

stations rise and then fall during storms. In equatorial regions

only the positive phase is observed. At high latitudes only

the negative phase is found. The major geomagnetic disturbance usually occurs during the positive phase, while during

the negative phase of temperate latitude bi-phase disturbance

the conditions are quiet. The negative phase in high-latitudes

recovers quickly, and seems associated with the rate of change

of magnetic field. The temperate negative phase has a slow

recovery. Often sudden commencement geomagnetic disturbances are accompanied by foF2 drops of half an hour or so. Think much F-layer variability is due to storminess.

A-66 Appleton, Sir Edward Victor and Piggott, W. R. , The morphology of storms in the F2 layer of the ionosphere. 1. Some

statistical relationships. Journal of Atmospheric and Terrestrial Physics, London, 2(4):236-252, 1952. 10 figs. , 10 tables,

5 refs. MH-BH, DWB--Variations of F2 critical frequency during ionospheric storms show a strong negative departure in

middle latitudes (Slough, Washington) usually coinciding with

well marked increases at magnetic equatorial stations (Huancayo, Johannesburg), both at sunspot maximum and minimum.

Stations widely separated in longitude show little correlation

but for the largest deviations there is a positive relation. In

temperate latitudes maximum deviation is a little before local

noon, recovering slowly. In local winter, disturbances are relatively rare in middle latitudes; there is no relation between

N. and S. Hemispheres. Near magnetic pole distribution of

+ and — deviations is symmetrical. --C. E. P. B.

A-67 Appleton, Edward V. , A note on the "sluggishness" of the

ionosphere. Journal of Atmospheric and Terrestrial Physics,

3(5):282-284, June 1953. ref. , 13 eqs. MH-BH-The physical

effect of recombination or attachment of electrons is to delay

the response of changes in electron density to changes in

rate of electron production. The effect in ionospheric measurements is discussed and the value ofocN (!ac= recombination coefficient) are calculated for D. E. and F layers.

--C E. P. B.

A-68 Appleton, V. Edward and Piggott, W. Roy, Ionospheric storms

and the geomagnetic anomaly in the F2 layer. Journal of Atmospheric and Terrestrial Physics, 3(2):121-123, Feb. 1953. 2 figs.

,

4 refs. DWB--Curves are given showing diurnal course of ratios

of critical F2 frequencies at Wakkanai (45° 4' N, 141° 7' E)

on disturbed/quiet days, and of Ottawa/Wakkanai. It is found

that the geomagnetic distortion anomaly causes a minimum of

F2 in forenoon and maximum in afternoon, and this anomaly is

accentuated by a weak ionospheric storm. —C.E. P. B.
21

A-69 Appleton, Sir Edward, Storm phenomena in the atmosphere

Archiv der Elektrischen Ubertragung, 273/7(6): 271-2/3, June

1953. 4 figs. , 4 reis. German and English summaries p. 271.

DLC--Recent advances in knowledge of F2 layer ionospheric

perturbations accompanying magnetic storms are summarized.

It is shown that these perturbations are subject to a marked

diurnal control. Differences between phenomena at high,

medium and low latitudes are identified, while an attempt

is made to relate ionospheric storm phenomena in medium

latitudes to the geomagnetic distortion of the F2 layer previously identified by the writer. For this range of latitudes

it is shown that the effect of a storm is to enhance the magnitude of the geomagnetic distortion already present. -- Author's abstract.

A-70 Appleton, Sir Edward and Beynon, W. J. G. , Radiocommuni- cation on frequencies exceeding predicted values. Institution

of Electrical Engineers, Proceedings, 100, Pt. 111(66): 192 -198,

July 1953. 8 figs. , 4 tables, 10 refs. , 5 eqs. DWB-Receipt

of Daventry short-wave signals at Gibraltar and Algiers shows

that communication is often established on frequencies higher

than predicted maximum usable frequencies. Examination shows

that during winter and equinoxes noon anomalies are often due

to variability in characteristics of the F2 region. In summer

the abnormal E region provides copious reflection at oblique

incidence. In Japan observations on 30 Mc/s show that transmissions on frequencies above F2 m. u. f. s. are due to abnormal region. --C. E. P. B.

A-71 Appleton, Sir Edward and Lyon, A. J. , Ionospheric layer formation under guasistationary conditions. (In: Physical Society

of London, The Physics of the Ionosphere, Pt. 1, The lowest

Ionosphere. London, Physical Society, 1955. p. 20-39.

)

A-72 Appleton, Edward V. , The anomalous equatorial belt in the F2- layer. Journal of Atmospheric and Terrestrial Physics, 5(5/6):

348-351, Nov. 1954. 3 figs. , 16 refs. DWB-The abnormal upward distension of F2 layer along a strip 4000 Km wide centered

on magnetic equator at noon, associated with low N , is re- placed by abnormally high N at 18 h, disappearing mapidly

after Oh. This crest is attributed to contraction of vertical extent. Curves of fF2 (Mc/s) 80°N - 80°S, March 1951 are shown

for 12, 21 and 9 h local time. --C. E. P. B.

A-73 Appleton, Sir Edward, Storms in the ionosphere. Endeavour,

London, 14(53):24-28, Jan. 1955. 3 figs. , 8 refs. , 5 eqs. DLC

—The author describes (1) the experimental radio-sounding of the

ionosphere for ionospheric forecasting giving the equations for

the conditions of reflection at vertical incidence for the ordinary case and for the extraordinary case; (2) the characteristics of the E and F layers; (3) behavior of ionosphere layers at

high latitudes; (4) the characteristics of ionospheric storm conditions in equatorial regions; (5) the variation of electron density
22

at noon in the E, F, and F2 layers; (6) the practical implications of storm changes in the F2 layer in relation to radio circuits and (7) the possible physical mechanisms of ionospheric

storms. --I. L. D.

A-74 Appleton, Sir Edward and Beynon, W. J. G. , An ionospheric

attenuation equivalence theorem. Journal of Atmospheric and

Terrestrial Physics, 6(2/3): 141-148, March 1955. 2 figs. , 6

refs. , 21 eqs. DWB—The phenomenon of radio-wave attenuation by way of ionospheric partial reflections and scattering

is examined theoretically, and an equivalence theorem, relating oblique incidence to vertical-incidence phenomena, is derived. For radio frequencies well in excess of the equivalent

critical frequency of the medium this may be written

M4 - - M O'- er where P is the fractional attenuation, f is the frequency, and

i<7 the angle of incidence in the oblique-incidence case. Where

the radio-wave electric vector is at right angles to the plane

of propagation, X is unity; when the electric vector lies in

the plane of propagation, X is equal to the usual obliquity

factor cos 2 i^. --Authors' abstract.

A-75 Appleton, Sir Edward, Rocket sounding in the upper air: confirmation of results inferred from radio measurements . Wireless World, London, 61(9):406-407, Sept. 1955. 4 eqs. DLC

—In connection with plans for the International Geophysical

Year, the article briefly describes methods of measuring pressures and deducing temperatures, and of measuring electron

density at a given height by the Doppler effect on the phase

velocity of radio waves near the rocket emitter. --C. E. P. B.

A-76 Appleton, Sir Edward V. ; 'Lyon, A. J. and Pritchard, Mrs. A.G.,

The detection of the Sq current system in ionospheric radio

sounding. Journal of Atmospheric and Terrestrial Physics,

7(4/5): 292-295, Oct. 1955. fig. , 7 refs. , 6 eqs. DWB--The

behavior of the E layer is inconsistent with CHAPMAN 's classical theory. One anomaly is due to the effect of electron

transport phenomena on diurnal variation of maximum electron

density. The noon delay of maximum differs from that given

by CHAPMAN's theory in showing a minimum at the equator

and maxima in 40^i and 30 S. This is attributed to the over- head current system. —C. E. P.B.

A-77 Appleton, Sir Edward V. ; Lyon, A. J. and Turnbull, Mrs. A. G.

,

Distortion of the E layer of the ionosphere by electrical cur- rents flowing in it. Nature, London, 176(4489) :897-899, Nov.

12, 1955. fig. , 7 refs. , 4 eqs. DWB--
23

Comparison of the maximum ionization density J/m, in the E-layer

with that predicted by Chapman's theory shows that a disturbing factor is present, dependent on latitude and even causing

afternoon values oiUm, near the equator to be less than cor- responding morning values. This factor is the vertical drift

of neutral ionization, connected with the S% overhead cur- rents which attain their maximum at 10-11 h local time and are E-W in middle and W-E in low latitudes. There is another factor besides cos ~x which causes.A^7ito be greater in low than

high latitudes. -C. E. P. B.

A-78 Appleton, Sir Edward (Edinburgh Univ. ), Regularities and ir- regularities in the ionosphere. (In: Beer, Arthur (ed. ), Vistas

in astronomu. pub. , London, 1955-1956. Vol. 2:779-790. 6

figs., table, I7refs., 18 eqs. ) DWB, DLC (520. 82 B415v)--

A general survey of ionospheric phenomena is given, in which

the regular variations of the E and Fl layers, as illustrated by

their intimate dependence on the sun's zenith distance, are contrasted with the anomalous behavior of the F2 layer. Using

results from the world's ionospheric stations, such anomalous

behavior is identified as geomagnetic distortion, most probably

due to atmospheric tidal action operating on an ionized medium

in the presence of the earth's magnetic field. As an illustration

of such geomagnetic control it is shown that, in the F2 layer,

the region of change-over from the Northern to the Southern

Hemisphere type of variation is more nearly coincident with

the magnetic equator than with the geographic equator. --Author's abstract.

A-79 Appleton, Sir Edward and Lyon, A. J. , Studies of the E layer

of the ionosphere, Pt. 1, Some relevant theoretical relationships. Journal of Atmospheric and Terrestrial Physics, 10(1):

1-11, Jan. 1957. 11 refs. , 34 eqs. DWB--As a preliminary to

a detailed study of the E layer, the theoretical basis is considered. The classical Chapman theory of ionized layer production, developed in 1931, does not explain some of the later

observations. Developments of the accepted theory are introduced to check experimental data, including assumptions that

maximum ionization density in E layer is quasistationary during daylight hours. Formulas are developed for variations from

the simple theory, especially the assumption that the E layer

is influenced by vertical drift. --D. E. P. B.

// A-80 Archiv der Elektrischen Ubertragung, Stuttgart, v. 1, July/Aug.

1947 - Latest issue seen, 8(7), June 1954. Monthly. Irreg.

Price: DM 15, 50 per quarter. Editor, 1954, Karl W. Wagner.

Printer, S. Hirzal Verlag. DLC--
24

This high quality monthly journal contains theoretical and

practical articles in all fields of radio, radar and TV technology, and in addition reviews of books and bibliographic

citations (2 pages per month). A number of articles on ionospheric and tropospheric propagation, sferics and meteor or radio astronomy can be found in each volume indexed under

the heading Ausbreitung electromagnetischer Wellen. Not

all articles are in German. For instance in Vol. 7, there is

an article in English by Appleton on Ionospheric storms.

--M. R.

A-81 Ardillon, Jeanne-Marie, Influence de l'heure locale dans les

perturbations ionospheriques. (Influence of local time upon

ionospheric disturbances. ) Academie des Sciences, Paris,

Comptes Rendus, 234(15): 1568-1571, April 7, 1952. DLC--

The daily variation of the critical frequencies along the vertical in the F2 layer at Poitiers and Washington was investigated for two years. Drops in frequency were observed between 18 and 24 h and around 6 h at Poitiers and between 22

and 6 h at Washington. It was found that two minima from

6 to 18 h enclose a diurnal maximum. The daily variations

in amplitude were more marked during the equinoxes than

during any other time of the year. —I. L. D.

A-82 Argence, Emile; Mayot, M. and Rawer, Karl, Contribution

a la etude de la distribution electronique de 1 'ionosphere et

de 1 'absorption des ondes courtes . (Contribution to the study

of distribution of electrons in the ionosphere and the absorption of short waves. ) Annales de Geophysique, 6(4):242-285,

Oct. -Dec. 1950. 13 figs. , 9 tables, 23 refs. , eqs. English

and French summaries p. 242. DBS—From a study of the absorption of reflected and transmitted radio waves, occuring

during the collision of electrons with neutral molecules, the

authors derive approximate formulas for calculating the absorption decrement <S 2 for complex layers. The model of

atmospheric ionization of Chapman, Nicolet, and Bossy are generalized and models with different variations of temperature and dissociation of Op the authors consider the problem

1) of parabolic variations of temperature below 100 km, and

2) of a rapid decrease of ionizable molecules above this

height. The significance of ionization to D and E layers is

discussed. --I.L.D.

A-83 Argence, Emile, Solution analytique approchee du probleme

de Poeverlein. (Approximate analytic solution of a Poeverlein

problem. ) Societe Royale des Sciences de Liege, Memoires,

Ser. 4, 12(1/2) :253-267, 1952. 5 figs. , 8 refs. , eqs. DLC--
25

Theoretical study of the trajectories of an electromagnetic

(radio) signal in an ionized medium under the influence of the

earth's magnetic field. The trajectories of normal and oblique

incidence rays in the plane of the magnetic meridian are calculated, neglecting variations in magnetic inclination. The

study shows that rays are deflected in opposite direction at

different heights; reflection occurring at lower altitude for

extra-ordinary rays and deviation differing markedly in the

case of "ordinary" rays. Thus ionospheric soundings can give

information on the ionization in various layers of the ionosphere. --M. R.

A-84 Argence, Emile; Rawer, Karl and Suchy, Kurt, Influence du

champ magnetique terrestre sur 1' absorption des ondes courtes dans 1 'ionosphere (incidence normale). (Influence of the terrestrial magnetic field on the absorption of short waves in

the ionosphere (normal incidence). ) Academie des Sciences,

Paris, Comptes Rendus, 236(2): 190-192, Jan. 12, 1953. fig. , 3 refs. , 3 eqs. DLC--Using a formula previously developed

by ARGENCE and assuming that the collisional frequency

follows an exponential law, calculations of the coefficient

of absorption K are made for a parabolic E layer with critical frequency 3. 5 Mc/s. The results are in good accord

with those obtained by the more regorous Appleton-Hartree

formula, but are markedly different from those given by the

Sellmeyer formula which neglects the earth's magnetic field.

However, the effective absorption of a ray reflected by the

layer, SK ". dz, is little different as the overall magnetic

field corrections roughly compensate. —Physics Abstracts,

No. 3461, 1953.

s A-85 Argence, Emil and Mayot, M. , Methode de determination des

hauteurs vraies des couches de 1 'ionosphere. II. Utilisation

de la valeur exacte de 1' indie e de refraction (cas du rayon

ordinaire) . (Method of determining the true heights of ionospheric layers, Pt. 2. Use of the exact value of the index of

refraction (case of ordinary rays). ) Journal of Geophysical

Research, 58(4): 493-496, Dec. 1953. table, 2 refs. DLC--

Determination of the characteristic parameters of an ionized

layer by the hypothesis where the variation of the electronic

density ensues from a parabolic law, to the first approximation, is described. Also shown is the application of the

exact value of the refractive index (APPLETON-HARTREE).

--Authors' abstract.
26

A-86 Argence, £. (S. P. I. M. Fribourg), Determination des traiectoires d'energie d'une onde ee propageant dans 1 'ionosphere.

Etude de deux cas particuliers (milieu transparent) . (Determination of trajectories of energy waves propagating in the

ionosphere. Study of two particular cases (in transparent

media). ) Annales de Geophysique, 10(3): 249-253, July/Sept.

1954. 2 figs. , 2 tables, 10 refs. , numerous eqs. French

summary p. 249. DLC- -Assuming an ionized transparent anisotropic medium, a direct method for the determination of energy

trajectories was developed. Trajectories for normal and oblique incidence are computed for various maximum critical frequencies along the magnetic equator. The mathematical theory

is presented in detail. An experimental study for oblique incidence is suggested. —A. A.

A-87 Arkhangel'sku, B. F. and Pabo, N. V., Rasprostranenie

radiovoln v vysokikh shirotakh. (Radio wave propagation in

high latitudes. ) Leningrad. Arkticheskii Nauchno-Issledovatel'skii Institut, Trudy, Vol. 124, 1938. 88 p. 55 figs.

,

6 tables, refs. at end of each chapter. DLC--A very thorough

treatment of all available data on Arctic troposphere and ionospheric radio propagation conditions and their disturbance

by solar, magnetic, auroral and static (sferics) activity. Actual recorder records as well as derived diagrams, tables and

curves are presented. Numerous references are given to the

sources (mostly 1932-1937 in Russian periodicals). Theoretical considerations are not neglected but applications to study

of atmosphere — especially the upper layers — and the aurora,

ionosphere, terrestrial magnetism and atmospheric electricity are emphasized. The study is based on data obtained in 1932/

33 and 1934/35 at Tikhaia (Calm) Bay in Franz Josef Land, and

other Polar Year stations in 1932/33.

A-88 Askar'ian, G. A. , ( Acceleration of charged particles in run- ning or standing electromagnetic waves. ) Zhurnal Eksperimental'noi Teoreticheskoi Fiziki, 36(2): 619-620, 1959. In Russian.

Transl. into English in Soviet Physics, JETP, N. Y. 36(i~e. 9),

No. 2:430-431, Aug. 1959. 3 refs.

A-89 Ataev, O. M., Vliianie neodnorodoi struktori ionosferi na

poglochshenie radiovoln. (Effect of inhomogeneous structure

of the ionosphere on absorption of radio waves. ) Radiotekhnika i Elektronika, 2(5):523-530, May 1957. 4 figs., 10 refs.

,

17 eqs. DLC--Amplitude and heterogenous structure of a multiple ionospheric reflected signal is treated theoretically.

Signal intensity from ionospheric layers is y that from regular

layers.
27

A-90 Australia. Commonwealth Scientific and Industrial Research

Organization. Fifth Annual Report for the year ending June 30. 1953. Canberra, 1953. 191 p. Meteorology, p. 131-134. DWB

—Progress made during the year on a number of projects in the

fields of radiophysics and atmospheric physics and astrophysics is described in Ch. 27, 28, 29, on pages 139-147. Special research on the ionosphere, twinkling of radio stars, general circulation, convection, micrometeorology, frost prevention, ozone, evaporation, artificial precipitation, cloud physics, nuclei, high level winds, climatic changes (rainfall),

solar physics, radio astronomy, etc. is reported and discussed.

Nearly 50 papers published by members of the several divisions

related to meteorology are cited. Costs and contributions for

the year are tabulated. —M. R.

A-91 Annan, E. and Benner, A. H. (Penna. St. Coll. Radio Prop.

Lab. ), Preliminary measurements of the vertical incidence

ionospheric absorption at 150 Kc/s. Pennsylvania. State College. Radio Propagation Laboratory, Contract AF 19(122) -44,

Basic Ionospheric Research, Technical Report, No. 6, Sept.

30, 1949. 23 p. 82 figs. , 5 refs. DWB-The results of manual and semi-automatic measurements of the reflection coefficient at vertical incidence at 150 Kc/s that were performed

during Feb. 27 to June 25, 1949 at State College, Penna. , are presented in graphs and analyzed on a diurnal basis. Although

incomplete, no midday hour reflections were obtained, the data

were used in an attempt to find a correlation between SID and

the absorption record. No conclusions are drawn. Theory of

measurement is discussed along with illustrated description

of equipment used.--W. N.

A-92 Bai, C. Lakshmi, Application of the generalized magnetoionic theory to the propagation of radio waves at the magnetic

dip-poles of the earth. Journal of Atmospheric and Terrestrial

Physics, ll(l):31-35, 1957. 2 figs. , 8 refs. , 8 eqs. DWBThe generalized magneto-ionic theory of BOOKER is applied to

the propagation of radio waves at the magnetic dip-poles of the

earth, to obtain rigorous values for the levels of reflection in

the ionosphere, of the magneto-ionic components. The propagation is discussed for various angles of incidence and for

operating frequencies greater and less than the magneto-ionic

frequency. The application of these results for finding out

the maximum usable frequency for a given transmission distance at the magnetic dip-poles is indicated. --Author's abstract.

A-93 Bailey, D. K. , On a new method for exploring the upper ionosphere. Terrestrial Magnetism and Atmospheric Electricity,

53(l):41-50, March 1948. fig. , table, 18 refs. , 6 eqs. DLC--
28

Conditions above the height of maximum ionization of the F2-

layer are not known. Measurements of the refraction experienced by radio waves arriving at the earth after passage

through the entire ionosphere can yield information about its

uppermost regions. An expression for the refraction of waves

which pass through a parabolic -layer model is derived, permitting frequencies to be specified within which profitable refraction measurements can be made. Either the sun, which emits

radio "noise, " or the moon, which can be used to return radio

waves originating on the earth, is a suitable extraterrestrial

source of waves. An experimental technique for measuring

refraction is described and discussed.

A-94 Bailey, D. K. , Bateman, R. , Berkner, L. V. (Washington,

D. C. ) and others, A new kind of radio propagation at very

high frequencies observable over long distances. U. S. National Bureau of Standards, Project NBS, 1405-21-6805, NBS

Report 1172, Sept. 28, 1951. 10 p. 5 figs. , 8 eqs. DWB--

Experiments on the propagation of radio waves with a frequency of 49. 8 Mc/sec over a distance of 1245 km are reported.

"Some preliminary speculations suggest that the mechanism

of this type of propagation may be scattering due to ever- present turbulence in the E region, and an approximate transmission equation is derived in terms of parameters describing

inhomogeneities in the E region. " The influence of passing

meteors is discussed. Hourly signal intensities are graphically represented and records showing enhancement and fadeout reproduced. --G.T.

A-95 Bailey, D. K. , The effect of echo on the operation of high

frequency communication circuits. Institute of Radio Engineers,

Professional Group on Antennas and Propagation, Transactions,

Vol. AP 6(4):325-329, Oct. 1958. 7 figs. , 4 refs. DLC--

There are two distinct kinds of echoes dependent on the illumination when occuring. Mode of operation and choice of frequency is discussed and summarized in a six point conclusion

toward minimizing the echo interferences. --W. N.

A-96 Bailey, D. K. , The effect of multipath distortion on the choice

of operating frequencies for high frequency communication circuits. Institute of Radio Engineers. Professional Group on Antennas and Propagation, Transactions, Vol. AP-7, No. 4:397-

404, Oct. 1959. 5 figs. , 12 refs. DLC--The m. u. f. as calculated for the lowest frequency usable to counteract the multipath distortion involves the new term MRF (multipath reduction factor) specified as a function of path length in this ionospheric model. --W.N.
29

A-97 Bailey, V. A., Smith, R. A., Landecker, K., Higgs, A. J. and Hibbard, F. H. , Resonance in Gyro-interaction of radio

waves. Nature, London, 169(4309): 911 -913, May 31, 1952. 3

figs. , 13 refs. DW6--Describes experiments in Australia in

which a gyrowave was radiated vertically as square pulses of

frequencies 1255 to 1880 kc/s, the local gyro-frequency being

estimated from magnetic data as 1530 kc/s. Theory predicted

that if another wave (the "wanted wave") is absorbed in the Elayer, resonance will occur. Two-humped resonance was observed on either side of 1530 kc/s. It is considered that this

method will lead to fuller knowledge of the E-layer, especially

its magnetic field. --C. E. P. B.

A-98 Bailey, V. A. , Study of the reflexion of waves from an inhomogeneous medium by means of a new first approximation to a solu- tion of the general, linear, second-order differential equation

and by means of iterations with convergence of the second order.

Pennsylvania. State Univ. Ionosphere Research Laboratory, Contract AF 19(122) -44, Scientific Report, No. 67, Aug. 1, 1954.

52 p. 16 refs. , numerous eqs. MH-BH--The propagation of a plane wave through three media, A. B. C in succession, of

which only A and B are homogenous, is studied and two formulas are obtained for the coefficient of reflection in terms of

solutions y and u of the Riccati equation corresponding to the

one-dimensional wave equation and of the wave equation itself.

Application to current work on reflection of long radio waves

from D region pointed out --From author's abstract.

A-99 Bailey, V. A. (U. of Sydney, Aust. ) and Goldstein, L. (U. of

111.), Control of the ionosphere by means of radio waves. Journal of Atmospheric and Terrestrial Physics, London, 12(2/3): 216-

217, 1958. 8 refs. DLC--As a radio wave traverses an ionized

gas, consequently raising its temperature, energy is produced.

But in the absence of some source of ionizing energy the gaseous

plasma disappears. Radio waves of sufficient intensity affect

the ionization produced by solar radiation or other agencies in

any region of the ionosphere, even when the temperature is as low as 250-300 K. When a rise in temperature has changed

the rates of different processes of diffusion, attachment and re- combination ionization can still be controlled by the establishment of radio stations on the ground especially when the controlling waves have their frequencies near the gyro-frequency of

electrons in the ionospheric region concerned. —N. N.

A-100 Bailey, V. A. (Univ. of Sydney), Some methods for studying

wave propagation in a uniform magneto-ionic medium. Journal of

Atmospheric and Terrestrial Physics, London, 12(2/3): 118-125,

1958. figs., 4 refs. , 34 eqs. DLC--
30

The difficulty in using the classical general formulas of

APPLETON, for determining the refractive and absorption indices and the polarization of each of the two wave-modes, is

primarily due to the presence of the radical teimp- Vrr 4S* + vLx where S is the reciprocal of a given complex number. This difficulty has been overcome by means of each of four methods of

calculation developed in the School of Physics of the University of Sydney. The first three, although previously published,

are here presented again but briefly. The fourth method makes

use of the following approximations:

-\/ 1-+ s 2 equals 4 + 3 s

2 or

s 4s 2 + 3

% + s* 4s 2 + 1

according as ls|

^ 1 (except when s^i- 1). On applying them

to APPLETON's formulas, by taking s = 2 Vi.v T

-* (1 + T + i£),

we obtain the good approximate formulas (32) and (33) for M2

(square of the complex refractive index) which, in effect, cover

all possible situations with an error not exceeding about \%.

Other applications of these approximations to v 1 + s a can be

made: for example to the polarization numbers R, for, with the

same value of

--Author's abstract.

A-101 Bailey, V. A. , Some possible effects caused by strong gyrowaves in the ionosphere, Pt. 1. Journal of Atmospheric and

Terrestrial Physics, New York, 14(3/4): 299-324, June 1959. 3

tables, 23 refs. , numerous eqs. DWB, DLC--The possible increases of collision frequencies v and electron densities n

caused by a powerful extraordinary circular gyro-wave in the

nocturnal lower E-region and in the day-time D-region are in=

vestigated on the basis of available laboratory experiments on

electrons in air and data concerning these regions. The resultant effects of such increases on this wave and on other waves

are then examined. It is found that some of these effects are remarkable in magnitude or in kind. Thus, notable self-distortion of gyro-waves and extremely large wave interaction can be

caused by such an extraordinary wave when the reduced equivalent electric force Z/p which it produces in the nocturnal

lower E region has the value 2. 5 V/cm per mm Hg measured

at room temperature. Other possible detectable effects which

may be caused at night when Z/p has a value between 2. 5 and

8 include changes in the airglow and in parts of some trails of

meteors and fast particles of solar or cosmic origin, changes

in radar echoes from such trails and transient changes in the

local magnetic elements. --Author's abstract.
31

A-102 Bain, W. C. ; Bracewell, R. N. ; Straker, T. W. and Westcott,

C. H. , The ionospheric propagation of radio waves of frequency 16 kc/s over distances of about 540 km. Institution of

Electrical Engineers, Proceedings, Pt. 4, 99(3): 250-259, July

1952. 11 figs. , 2 tables, 19 refs. , 9 eqs. DBS—Previous measurements over 90-200 km distances when compared with ex- perimental results obtained over a distance of 535 km show a marked change in the propagation characteristics of waves at

16 kc/s frequency. The height of reflection varies with the

inclination of the sun's rays. From 90-535 km the apparent

height is about 74 km at midday and about 92 km at night.

Experimental results are discussed and presented in tables.

-W.N.

A-103 Bain, W. C. , Observations on the propagation of very long

radio waves reflected obliquely from the ionosphere during a

solar flare . Journal of Atmospheric and Terrestrial Physics,

3(3):141-152, April 1953. 6 figs., table, 19 refs. MH-BH--

Describes measurements of amplitude and phase of 16 kc/s

sky wave Rugby to Aberdeen. Normal diurnal variation of

apparent height of reflection at normal and oblique incidence

is shown and sudden field anomalies at Aberdeen and Edinburgh during solar flares illustrated. It is found that during

a moderate flare with large zenith distance of sun there is a change of apparent reflection height for vertical but not for

oblique incidence. Phenomena are attributed to a double

structure of D layer, the lower layer (at 70 km) being responsible for obliqueincidence propagation (including atmospherics)

and the upper affected by solar radiation during a flare.

"C.E.P.B.

A-104 Bain, W. C, The angular distribution of energy received by

ionospheric forward scattering at very high frequencies. Institution of Electrical Engineers, Proceedings, Pt. B, 105(8):

53-55, 74-75, 78, 1958. 3 figs. , 6 refs.

A-105 Bain, W. C. and Glass C. B. I. , The polarization of very long

radio waves reflected from the ionosphere at oblique incidence.

Institution of Electrical Engineers, London, Proceedings, Pt. C,

103(4) :447-448, Sept. 1956. table, ref . , 2 eqs. DLC-A study

of some additional evidence has been made to determine the

polarization of radio waves reflected from the ionosphere at

16 kc/s over a transmission path 540 km long. The ratio between the amplitudes of the vertical and horizontal electric

fields is found to be appreciably greater than unity, the mean

value of the determinations made here being 5. --Authors' abstract.
32

A-106 Baird, K. , High multitude radio reflections from the F2 layer

of the ionosphere at Brisbane. Australian Journal of Physics,

7(1):165-175, March 1954. 5 figs. , 2 tables, 5 refs. MH-BH--

Continuous night-time records of multiple F2 reflections at

normal incidence have been made at a fixed frequency. The

echo patterns have been classified, and qualitative explanations given in terms of humped ionization contours, extending

the work of PIERCE and MIMNO (1940). These patterns have

been studied also by a variable gain technique. It is concluded that accurate measurements of reflection coefficients

cannot be made by this means. Statistical analyses of occur- rences of up to the 10th multiple showed that: a) if no account

is taken of presence or absence of Es , the frequency of occurrence increases towards dawn; b) there is no correlation between the number of reflections observed and the virtual height

of the region; c) there is no correlation with "range duplications"; d) inverse correlation between high multiple F reflections and presence of Es occurs only when the lower region is

blanketing; e) there is no correlation between high multiples

and the travelling disturbances described by MUNRO. A

study of the presence of very high multiples revealed maxima

at the equinoxes. Oblique incidence recording gave no re- flections beyond the fifth multiple. --Author's abstract.

A-107 Baker, W. G. and Martyn, David Forbes, Conductivity of the

ionosphere. Nature, London, 170(4339): 1090-1092, Dec. 27,

1952. 2 figs. , 19 refs. , eqs. Singer, S. F. , Maple, E. and

Bowen, W. A. , Dynamo currents and conductivities in the

earth's upper atmosphere. Ibid. , p. 1093-1094. fig. , 15 refs.

DWB--By existing theories of ionospheric winds and ionization, conductivity (calculated as less than 4 X 10"^ emu/cm)

cannot account for observed geomagnetic daily variations by

dynamo theory, which requires 5 X 10"° emu/cm. Formulas

for various types of conductivity are graphed according to

height and latitude and an expression for height-integrated

effective conductivity deduced. This gives an adequate cur- rent mainly between 110 and 150 km. , but near magnetic equator in a shallow layer at 100 km. The second paper describes

rocket measurements. At time of maximum H at Huancayo,

a very rapid decrease (4 milligauss) was found at 93-105 km

interpreted as due to an E-W current in a large horizontal

sheet, probably produced bv Hall polarization.

-C.E.P.B.

A-108 Baker, W. G. (Amalgamated Wireless Australasia, Ltd. ) and

Martyn, D. F. (Radio Research Board of Australia), Electric

currents in the ionosphere. Pt. 1-3. Royal Society of London,

Philosophical Transactions, Ser. A, 246(913): 281 -320, Dec. 16,

1953. figs. , refs. , eqs. DWB--
33

In the first paper the authors examine quantitatively the theory

that the effective conductivity of the ionosphere in the dynamo

theory is enhanced by the polarization of the Hall current. The

effective conductivities over most of the earth were found to

satisfy this theory. In a narrow strip at the equator the conductivity is enhanced, accounting for the excessively large

magnetic variations found there. In the second paper ( by

BAKER) three examples are given of the flow of current in plane

sheets, due to the application of steady electric fields, for

cases where this inhibiting polarization is absent, partial or complete, respectively. In the third paper (by Martyn) the mass

motion and velocity of the ionization in the ionosphere under

the influence of an electric field, and/or atmospheric wind are discussed. --M. R.

A-109 Balser, M. ; Smith, W. B. and Warren, E., On the reciprocity

of HF ionospheric transmission. Journal of Geophysical Research, 63(4): 859-861, Dec, 1958. (QC811. J6) DLC--Experiments of July-Aug. 1957 with oblique sounding equipment,

transmitting pulses of 35 micros ec. duration 15 times per sec. between the terminals Ottawa and Winnipeg are reported. Fade

in one direction was not duplicated in the other, and with les- ser exceptions, the reciprocity appears pretty equal. Whether

the effects are purely ionospheric will be checked in the fut- ure. --W. N.

A-110 Bandyopadhyay, P. , Models of the lower ionosphere as may

be inferred from absorption results. Indian Journal of Physics,

31(6): 297-308, June 1957. 8 figs. , 10 refs. , 2 tables, 11 eqs.

DLC--Values of deviate and non-deviate absorption and their

variations with cos % are calculated for some of the proposed

D and E region models. The results obtained are compared

with the available experimental data. It is found that so far as the E region is concerned, A. P. Mitra's theoretical model

is most consistent with the observed diurnal variation of absorption. For the E region, the model as proposed by Jones,

is found to be unacceptable. Conditions which are to be

satisfied by an acceptable E region model are discussed. -- Author's abstract.

A-lll Bandyopadhyay, P. (Univ. of Calcutta, India), The early morn- ing E2-layer and some evidence of pre-sunrise F-layer "splitting"

Journal of Atmospheric and Terrestrial Physics, N. Y. , 16

(l/2):84-92, Oct. 1959. 6 figs. , 12 refs. DWB, DLC--Two

early morning phenomena, one relating to the E2-layer cusps

and ridges and the other to the F-layer traces as observed in

the h'-f records made at Haringhata (Calcutta) are described

and discussed. The early morning E2-layer cusps and ridges

are found to be a regular sunrise feature of the ionograms.
34

They show marked seasonal variation o! character and frequency of occurrence and are most prominent in winter. The

early morning F-layer records show, also in winter, a peculiar kind of "splitting" which is quite distinct from regular F1-,

F2-bifurcation. This F-layer "splitting" and its possible bearing on the E-layer phenomena described above are discussed.

Representative ionograms of the two phenomena are given.

—Author's abstract.

A-112 Banerjee, S. S. and Mehrotra, R. R. , Multiple reflections

and undulations in the F2-region of the ionosphere. Science

and Culture, 16(2):72-73, Aug. 1950. 3 figs. , 3 refs. MH-BH

—The anomalous behavior of the amplitude of multiple reflected

pulses from the F2 region was found to occur even when the

transmitter and receiver were situated very close to each other.

Photographs of observations, showing the amplitude of higher

order echoes to be higher than that of lower order echoes, are presented and analyzed. It is suggested that the anomalous

variations in intensity of the reflected waves from the ionosphere are produced by undulations in the lower structure of

the F2 region. -I. L. D.

A-113 Banerjee, S. S. ; Mehrotra, R. R. and Raj an, V. D., Scattering of radiowaves and undulations in the ionosphere. Science

and Culture, Calcutta, 17(4):45-46, July 1951. refs. DWB--

The authors discuss a type of ionospheric scattering which is

observed before the frequency of transmission reaches the

critical frequency, and the centers of which appear to be in

the F2 region of the ionosphere and which may be observed

with low power transmitters. A description is given of this

ionospheric scattering as observed by radiation of pulses at

vertical incidence during evening and night, and photographs

are included. —I. L. D.

A-114 Banerjee, S. S. and Mehrotra, R. R. , Intensity variation of

short wave signals and their bearing; on the ionosphere. Journal

of Scientific and Industrial Research, Delhi, U(l):ll-13, Jan.

1952. 4 figs. , 15 refs. DWB--Theory of fading and history of

work along that line is briefly reviewed. Fading patterns are classified under periodic and random types, with many subdivisions of these. This classification system has proven useful in predicting nature of fading patterns. Special interest attends periodic fading patterns. It is possible to calculate from

records obtained during this type (such as illustrated) the rates

of change of electron density and the semi-thickness of change

of electron density and the semi-thickness of the ionized layer.

Also, undulations in ionosphere affect short wave radio fading

patterns, such as illustrated. —M. R.
35

A-115 Banerjee, S. S. and Mehrotra, R. R. (Benares Hindu Univ.

)

Equivalent paths of the extraordinary waves for oblique inci- dence at the ionosphere. Journal of Scientific and Industrial

Research, New Delhi, Sec. B, ll(6):216-218, July 1952. fig.

,

3 refs. , 10 eqs. DWB—Presents the method of deriving an

equation useful for drawing the curves of the extraordinary

wave, explaining the formation and features of the fading

pattern observed near the maximum usable frequency (m. u. f. ). --W. N.

A-116 Banerjee, S. S. and Banerjee, D. K. (Eng. Coll., Banaras

Hindu Univ. ), Scattering of radio waves and horizontal gradient of ionization in the ionosphere. Journal of Scientific

and Industrial Research, Sec. B, 12(6):277-279, June 1953.

3 figs. , 4 refs. DWB--Multiple scattered signals obtained

at vertical incidence with a low-power (2. 5 kW) pulse transmitter are discussed. The mode of propagation between

ground and ionosphere is explained and illustrated. From

echoes obtained on Feb. 14, 1953 the horizontal gradient of

ionization in the atmosphere is determined and found to be

in agreement with electronic densities measured by the Research Department of the All India Radio. --G.T.

A-117 Banerjee, S. S. ; Banerjee, D. K. and Raj an, V. D., (Eng.

Coll. , Banaras Hindu Univ. ), Scattering of short wave radio

signals and their bearing on the ionosphere. Journal of Scientific and Industrial Research, Sec. A, 12(6): 278-282, June 1953

5 figs. , 15 refs. DWB--After reviewing earlier investigations

of scattered radio echoes, the authors report recent research

on the scattering of short wave radio signals conducted at the

Banaras Hindu Univ. , Engineering College laboratory. Observations were made with a high-power transmitter at oblique

incidence and a low-power transmitter at vertical incidence.

Results of the observations are discussed. A marked cor- relation is found to exist between the thickness of the ionized layer and the intensity of scattered signals. --G. T.

A-118 Banerjee, S. S. and Banerjee, D. K. (Eng. Coll. , Banaras

Hindu Univ. ), Variation of horizontal gradient of ionization

in the ionosphere. Journal of Scientific and Industrial Research, Sec. B, 13(l):72-73, Jan. 1954. 2 figs. , table, 7

refs. DWB--Values of the horizontal gradient of ionization

(difference per 100 km between critical frequencies for F2

region at Banaras and at Delhi) in the morning and in the

afternoon are presented for Oct. and Dec. 1952. Variations

of the gradient show much wider range and higher average in

the afternoon than they do in the morning. --G. T.
36

A-119 Banerjee, S. S. and Surange, P. G. (Engr. Coll., Banaras

Hindu Univ. , Banaras), Scattering of radio waves and the

horizontal gradient of ionization in the ionosphere. Science

and Culture, Calcutta, 21(12): 750-753, Junel956. 3 figs.

,

2 tables, 4 refs. , 4 eqs. DLC--Besides the normal horizontal

gradients of ionization in the ionosphere there are shown to be

short regions with sharp horizontal gradients which modify the

propagation of radio waves so as to produce non-linear P'f

curves for back-scatter. A uniform ionosphere (linear) curve

and a non-uniform (non-linear) case are shown graphically,

based on pulse signals on Feb. 10 and Feb. 15, 1955, res- pectively (at Banaras, India). Data are also presented in

tables. --M. R.

A-120 Banerji, R. B. , Studies on the sporadic E-layer. Indian Journal

of Physics, 25(8):359-374, Aug. 1951. 6 figs. , table, 11 refs.

,

13 eqs. DLC --This investigation shows that: I) the echo of a transmitted radio signal consists of one component due to ran- dom scattering and another component due to steady reflection, hence 2) the E-region consists of one ion-cloud region

and one regularly reflecting region. A method for estimation

of the average number density of electrons in the cloud shows

the number density to be below that required for total reflection of the transmitted wave. An advanced formula that can

be applied to investigations of the structure of that part of

the E-region that gives rise to the steady echo is discussed.

--W.N.

A-121 Banerji, R. B. , Some studies on random fading characteristics.

Physical Society of London, Proceedings, Ser. Bf 66(2): 105-114,

Feb. 1, 1953. 4 figs. , 13 refs. , 32 eqs. DWB--The theory of

random fading of pulses singly reflected from the ionosphere

is examined. Velocity distribution of fading is found to be

independent of the power spectrum of the returned wave. This

invalidates the accepted explanation of certain observed departures from theory. An alternative explanation is given and

discussed. --Author's abstract.

A-122 Banerji, R. B. , Autocorrelogram of randomly fading waves

with applications to wind measurements at 150 kc/s. Pennsylvania State Univ. Ionosphere Research Lab. , Contract AF

19(122)-44, Scientific Report, No. 59, March 15, 1954. 29 p.

6 figs. , table, 7 refs. , 30 eqs. DWB--The greatest difficulty

in the computation of wind velocities from the autocorrelogram

analysis of radio wave fading patterns has so far been supposedly random fluctuations of the derived autocorrelograms.

A method is developed to test the significance of autocorrelograms. It is shown that no more than 250 independent data on
37

the original fading pattern are needed to distinguish between

turbulent and drift velocities. The power spectrum that can

be expected from an irregular ionosphere is also considered.

It is found that the autocorrelograms of the fading of 150 Kc/s

waves obtained bear out these discussions. The orientation

of the antennae seems to have a very profound influence and

it may be expected that the fading observed with two adjacent

aerials at different orientations may yield as much information

regarding wind velocities as spaced receiving aerials. --From

author's abstract.

A-123 Banerji, R. B. , The mechanism of fading of 150 kc pulses.

Pennsylvania State Univ. Ionosphere Research Laboratory,

Contract AF 19(122) -44, Scientific Report, No. 71, Nov. 15,

1954. 29 p. 9 figs. , table, 17 refs. DWB--A statistical

theory of fading due to random absorption of downcoming

waves has been worked out. Comparison of this with the

theory of random scattering indicates a major point of difference which can be distinguished experimentally. Statistical results obtained with 150 kc waves at the Penna. State

Univ. indicate that it is the absorption phenomenon which

gives rise to the fading of these waves. On the basis of

this result, the statistical theory has been extended to yield

a method for the measurement of the height of the irregularities which give rise to the fading. Results indicate a diurnal

variation — lower heights in the day and higher at night. A

discrepancy with the theory of random fading which was noticed by previous authors working with short waves has not

appeared with data at Penna. State Univ. The reason for the

difference is discussed. --Author's abstract.

A-124 Banerji, R. B. , Distribution-in-speed of fading; of 150 kc/s

waves. Nature, London, 176(4472): 131, July 16, 1955. fig.,

5 refs. DWB-No significant difference from normality was

found in the distribution of speed of fading of 150 kc/s waves.

This bears out the prediction that similarity to the normal distribution would be more pronounced for long than short waves.

--C. E. P. B.

A-125 Banerji, R. B. , The autocorrelogram of randomly fading waves.

Journal of Atmospheric and Terrestrial Physics, 6(1): 50-56, Jan.

1955. 3 figs. , 6 refs. , eqs. DWB--The autocorrelograms of

fading patterns from rough ionospheres characterized by pure

drift and pure turbulence are calculated and that from a combination of the two is deduced. The reality of oscillations

in the tail of the correlogram, and hence the distinction between the two types, can be established if more than 220

points are available. A correlogram obtained by R. W.E. McNicol (1949), which resembles the theoretical one for a drifting ionosphere, is regarded as real. --C. E. P. B.
38

A-126 Banerji, R. B. , Methods of analyzing fading records from

spaced receivers, including preliminary analysis of such

data at 75 Kc/s. Pennsylvania. State Univ. Ionosphere Research Laboratory, Contract AF 19(604)-1304f Scientific Report No. 81, Jan. 15, 1956. 53 p. 8 figs. , table, 12 refs.

,

63 eqs. DWB--The statistics of the fading of radio waves

from spaced receivers has been reconsidered to interrelate

the existing methods of drift measurement and compare their

effectiveness. An extension of the Putter technique has been

made to the case of random motions and indications are given

concerning the extension to the case of anisotropy. Experimental results concerning the fading of 75 kc/s waves observed at State College during 1955 are briefly discussed.

—Author's abstract.

A-127 Banerji, R. B. (Indian Statistical Inst. , Calcutta), Method

of measuring ionospheric winds by fading at spaced receivera.

Journal of Atmospheric and Terrestrial Physics, N. Y. , 12(4):

248-257, 1958. 3 figs. , 12 refs. , 31 eqs. DLC--The different

statistical methods developed for the measurement of ionospheric drifts by spaced receivers have been reviewed and the

essential unity of the basic model brought out. The geometrical method of PUTTER and the probability-distribution method

of the Cambridge School have been merged into a single method which promises to be less laborious than the autocorrelation methods but of comparable accuracy. --Author's abstract.

A-128 Baral, S. S. (Ionospheric Lab. , Inst, of Radio Phy. and Electronics, Univ. Col. of Sci. , Calcutta), Studies on sporadic E.

Journal of Scientific and Industrial Research, New Delhi, Sec.

A, ll(7):290-296, July 1952. 4 figs. , 26 refs. DWB--Author

discusses the results of his analysis of world data, 1945-1951,

available on sporadic E (Es) of which the highlights are: I. The

main source of Es ionization is the meteoric impacts. 2. Both

intensity and frequency of occurrence have two maxima: (a)

one near the equator and (b) another near 70 lat. The author

speculates on whether or not the pronounced effect found over

the geomagnetic equator has some bearing on the upper atmospheric (electro-jet) current system over Huancayo. 3. The

diurnal variation of Es falls off from the equator towards the

higher latitudes. 4. Of the two theories of the structure of

the Es, the "thin layer" and the "ionized patch, " the latter is

strongly favored because of observational evidence. --W. N.

A-129 Barber, N. F. and Crombie, D. D. (both, Dep. Scientific &

Indust. Res. , Lower Hutt, New Zealand), V. L. V. reflections

from the ionosphere in the presence of a transverse magnetic

field. Journal of Atmospheric and Terrestrial Physics, N. Y.

16(l/2):37-45, Oct. 1959. 4 figs., 14 refs. , 20 eqs. DWB, DLC
39

--The reflection coefficient is found for waves that are incident on a sharply bounded ionosphere and have their electric

vector in the plane of incidence. The earth's magnetic field

is assumed to be horizontal and perpendicular to the direction

of propagation. Hence, the analysis is appropriate for propagation round the magnetic equator. It is found that the reflection coefficient for waves incident from the west is numerically greater than that for waves incident from the east, when

the angle of incidence is large. --Authors' abstract.

A-130 Barre, M. and Rawer, Karl, Une perturbation ionospherigue

extraordinaire observee en terre Adelie. (An extraordinary

ionospheric disturbance observed in Adelie Land. ) Annales

de Geophysique, 6(4):309-317, Oct. -Dec. 1950. 7 figs.

French and English summaries p. 309. DBS—A detailed analysis of the ionospheric disturbance that was observed at

Adelie Land and in its vicinity between Feb. 2 and 5, 1950.

The high absorption occurring in a limited region of the atmosphere is attributed to increased ionization in the D as

well as in the F2 layer. —I. L. D.

A-131 Barre, M. and Rawer, K. , Quelgues resultats d' observation

ionospherigues effectuees ores de la Terre Adelie. (Some re- sults of ionospheric observations made near Adelie Land.

)

Journal of Atmospheric and Terrestrial Physics, 1(5/6) :3ll-314,

1951. fig. , 3 refs. DWB—The ionospheric observations in

this region show many anomalies due to the proximity of the

magnetic pole. The E, F, and F2 echoes are often scattered,

especially the F2 echoes, due to ionic clouds at the E level.

Characteristic photographs are added. --A. A.

A-132 Barron, D. W. ,

' Waveguide Mode' Theory of radio wave pro- pagation when ionosphere is not sharply bounded. Philosophical Magazine, 4(45): 1068-81, Sept. 1959. -Propagation of radio

waves can be treated by considering space between earth and

ionosphere as waveguide and discussing properties of various

waveguide modes; method of calculating mode characteristics

for any horizontally stratified ionosphere in which electron

density and collision frequency vary with height in some arbitrary prescribed manner; theory given in full for flat, perfectly

conducting earth with no magnetic field.

A-133 Baruah, H. K. and Baruah, Parukutty, A high precision ionos - phere sounding eguipment. Science and Culture, Calcutta,

17(7):305-306, Jan. 1952. 2 figs. MH-BH-Brief description is

given of new radar equipment installed at the Institute of Nuclear Physics, Calcutta. The instrument is claimed to have an

accuracy better than I km as opposed to 10 km which is declared to be the accuracy of apparatus used up to present. The
40

instrument is being used for studies on magnetoionic splitting.

Some technical details concerning the equipment are indicated

and two photos of echoes presented. --G. T.

A-134 Bateman, R. (Page Communications, Eng. Inc., Wash. D.C.);

Finney, J. W.; Smith, E. K. ; Tveten, L. H. and Watts, J. M.

(all, Natl. Bur. of Standards, Boulder, Colorado), IGY obser- vations of F-layer scatter in the Far East. Journal of Geophysical Research, Wash., D. C, 64(4):403-405, April 1959.

2 figs. , tables, 2 refs. DLC—Peculiar signal enhancements

observed during transmissions at 36 to 50 Mc/s between the

Philippines and Okinawa appear to represent F-layer scatter.

These signals are observed nightly for periods of several

hours during the months of September and October. Pulse

tests indicate F-layer heights for these signals. Considerable pulse broadening is observed and the signals generally

arrive from somewhat off the great circle path. --Authors'

abstract.

A-135 Bates, David R. , The temperature of the upper atmosphere.

Physical Society of London, Proceedings, B, 64:805-821, 1951.

7 tables, 51 refs. , 23 eqs. DWB--Assuming that 110 km temperature is about 300 K and particle concentration 7.4 X 10*2

/cm3, effects of various temperature gradients up to 200-500

km surmounted by an isothermal region are tabulated and the

thermal equilibrium in the F region studied. The estimate,

based on radio measurements, of the energy gained from ionizing photons is insufficient to balance loss by conduction

and emission, and it is suggested that the estimated gain of

energy is too low, heat being also supplied to upper atmosphere by unobservable ionization. This should vary with sunspot cycle, agreeing with a suspected sunspot cycle in var- iation of level and temperature of ionosphere layers.

--C.E.P.B.

A-136 Bates, D. R. (ed. ), The earth and its atmosphere . N. Y.

,

Basic Books, Inc. 1957. 324 p. figs. , photos, tables, bibliog.

p. 303-308. DLC (AC806. B34) Earlier edition issued under

title, The Planet earth, London, Pergamon Press, 1957. 312 p.

The 17 chapters in this up-to-date collection of articles contain

discussions by experts in the several fields of: 1) The IGY (S.

CHAPMAN); 2) Origin and age of earth (KUIPER); 3) Earth's

core (K. E. BULLEN); 4) Crust (J. T. WILSON); 5) Oceans

(DEACON); 6) Magnetism (VESTINE); 7) Composition and

structure of atmosphere (D. R. BATES); 8) Climate (EADY); . 9) General circulation of atmosphere and oceans (EADY);

10) Ice ages (OPIK); 11) Meteorology (B. J. MASON); 12) Ionosphere (RATCLIFFE); 13) Airglow (D. R. BATES); 14) Aurorae

and magnetic storms (FERRARO); 15) Meteors (LOVELL);
41

16) Cosmic radiation (J. G. WILSON); 17) Genesis of life

(HALDANE). Numerous illustrative graphs and schematic

diagrams and tables are included. The information, while

not presented in a technical style, is substantial enough

to satisfy anyone who is not an authority on the given subject. (For listing of contents, see Pt. Ill of this issue of

MAB; articles abstracted separately. )--M. R.

A-137 Bauer, Siegfried J. , A possible troposphere-ionosphere re- lationship. Journal of Geophysical Research, 62(3):425-430,

Sept. 1957. 2 figs. , 6 refs. DLC—This analysis shows statistically significant relationship between tropospheric frontal

passage and minimum virtual height of the F2 layer and is discussed in light of Martin's theory, in consequence showing

consistency with the concept of troposphere-ionosphere dynamic coupling. --W.N.

A-138 Bauer, Siegfried J. (U. S. Army Signal Engin. Labs. , Fort

Monmouth, New Jersey), An apparent ionospheric response

to the passage of hurricanes. Journal of Geophysical Research,

Wash., D. C. 63(l):265-269, March 1958. 5 figs. , 5 footrefs. DLC.

A-139 Bauer, Siegfried, J. and Daniels, Fred B. (both, U. S. Army

Signal Res. & Dev. Lab. , Fort Monmouth, N. J. ), Measure- ments of ionospheric electron content by the lunar radio tech- nique. Journal of Geophysical Research, Wash. , D. C. , 64(10)

:1371-1376, Oct. 1959. 7 figs. , 9 refs. , eqs. DLC-Measurements of the Faraday rotation of lunar radio echoes on a frequency of 151 Mc/s are used to determine the time variation

in the total ionospheric electron content. Absolute values of

ionospheric electron content are determined from these measurements in conjunction with information on the electron content below the F2 peak computed from vertical incidence sounding data. Diurnal, day-to-day, and seasonal variations in the

total electron content are presented. The ratio na

: nfcof the

number of electrons above the F2 peak to that below is found

to be in the order of 4 to 5 during three summer nights (June)

before sunrise and about equal to 3 after sunrise. For two days

in November the ratio n : n, is found to be equal to about 3

both before and after sunrise. Possibilities of inferring other

characteristics of the upper ionosphere from observed variations in the total electron content are briefly discussed.

--Authors' abstract.

A-140 Beagley, J. W. (Dir. Geophysical Obs. , Dept. of Sci. & Ind.

Res. N. Z. ), Ionosphere research. (In Simpson, Frank A. (ed. ), The Antarctic today. Wellington, Reed, 1952. p. 279-293.

fig. , photos, 15 refs. ) DWB--
42

A survey of the research which has been and is being done in

New Zealand and the neighboring Antarctic regions in an attempt to solve the fundamental problems of ionospheric re- search. First proof of the Kennelly-Heaviside layer is said

to have been made by APPLETON and BARNETT (a New Zealander) in 1924 . The places where research

on ionospheric wave propagation is carried on are listed and

the work described (Christchurch, Raoul Island in Kermadec

Group, Campbell Island, Pitcairn Island, Rarotonga, Fiji).

Plates show the layout of the weather station on Marion Island. --M. R.

A-141 Becker, Walter, Uber die Dampfung der ausserordentlichen

Komponente in der El-Schicht der Ionosphare. (On the damping of the abnormal component in the El layer of the ionosphere. ) Journal of Atmospheric and Terrestrial Physics, 1(2):

73-81, 1950. 6 figs. , 4 refs. , 2 eqs. MH-BH--The experimental observation, that no extraordinary radio echoes can be re- ceived from the normal E layer around sunrise and sunset for

frequencies from I. 39 to 2. 5 Mc/sec. , is shown to be in ac- cordance with theory. Many experimental and theoretical

curves are presented in support of this. --From author's abstract.

A-142 Becker, Walter and Dieminger, Walter, Zur Definition der

E2-Schicht. (On the definition of E2 layer. ) International

Council of Scientific Unions. Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 126-

138. 6 figs. , 2 tables, 21 refs. English and French summaries p. 138. DWB--A study of the thin homogenous layer between the E and F layer which is called the E2 layer. It was

discovered as a result of observations with high power, multifrequency recording system. The E2 layer is observed with

great regularity, is very stable and easily distinguished from

the other intermediate layers that are seldom recorded at Lindau; the limiting frequency is only 0-2 to 0-3 MHz greater

than that of the El layer, and shows direct dependence on

solar altitude*. --M. R.

A-143 Becker, Walter, Typische Streuprozesse radiofreguenter

Strahlung an Elektronenwolken der sporadischen Es-Schicht

dargestellt an Hand ausgewahlter Durchdrehaufnahmen.

(Typical processes of scattering of radio waves by electron

clouds in the sporadic E layer, as shown by selected revolving-camera photographs. ) International Council of Scientific

Unions. Mixed Commission on the Ionosphere, Canberra,

Australia, Aug. 24-26, 1952, Proceedings, p. 186-193, pub.

1953. 6 figs., 12 refs. DWB--
43

The correctness of T. L. ECKERSLEY's disclosure of the influence of electron clouds of the sporadic E layer on the propagation of electromagnetic waves which can be of different

horizontal extension is confirmed by a number of selected

multifrequency photographs representing Eckerley's typical

scattering phenomena in E clouds made at the Institute for

Ionosphere Studies at Linden. —A. M. P.

A-144 Becker, Walter, Tvpische Streuprozesse radiofreauenter

Strahluna an Elektronenwolken der sporadischen Ea^Schicht

dargestellt an Hand ansgewahlter Eoholotunqsaufnahmen mit

veranderlicher Frequenz. (Typical processes of scattering of

radio waves from sporadic E clouds illustrated with selected

echo sounding records of varying frequency. ) Arohiv der

Elektrisohen tfbertragung, 7(8):375-378, Aug. 1953. 6 figs.

,

12 refs. DLC—Various possible modes of scattering from

sporadic E clouds are considered and typical (P' r F) records

are reproduced to illustrate these modes.—Electrical Engr.

Abstracts, No. 1255, 1954.

A-145 Becker, Walter, Winde und turbulente Lnftstromunaen in der

Ionosphere. (Winds and turbulent air currents in the ionosphere. ) Archiv fur Meteorologie, Geophysik und Bioklimatologie, Ser. A, 6(3/4) :417-439, 1954. 6 figs. , 5 tables, 51

refs. English and French summaries p. 417-418, DLC—Methods

of observation are classified as non-electric (rockets, volcanic dust, aurora, luminous clouds, meteor trails), and radiowave techniques (1 to over 1000 m). The range of velocities

is 50-400 m/s (one observation of 1100); maximum frequency

is 60 m/s at 80-120 km and 100 m/s in F layer, but standard

deviation is several hundred percent. Determinations of

turbulence are discussed; their period is inversely proportional to observation radio frequency. In the F-layer the propagation of deviation centers is proportional to the geomagnetic character figure. In the E-layer solar and lunar tides

give a velocity range of 35 and 25 m/s. -C. E. P. B.

A-146 Becker, Walter, Uber ein Verfahren zur routinemassiqen

Bestimmung der wahren Verteilung der Elektronendichte in

einer Ionosphefrenschicht aus den Durchdrehaufnahmen dieser

Schicht. (A method for routine determination of the true distribution of electron density in an ionospheric layer from

sweep frequency records for this layer. ) Archiv der Elektrisohen iJbertragung, Stuttgart, 10(5): 207-214, May 1956.

9 figs. , 2 tables, 4 refs. German and English summaries

p. 207.

^mm^m^m
44

Also his: Methods graphique pour la determination courante

des distributions vertic ales de la densite electroniqrue dans

les couches ionospheriques d'apres les enregistrements

obtenus par balayage de frequence. (Graphical method for

routine determination of vertical electron density distribution in ionospheric layers from sweep frequency, records.

)

Annales des Telecommunications, Paris, 12(5): 141 -145, May

1957. 6 figs. , table, 3 refs. DLC--The Booker-Seaton (1940)

method of determining electron density from height and sweep

frequency records is discussed critically and illustrated, and

a generalized method is extended to enable one to calculate

the electron density and the form of the ionospheric layer

(whether Epstein, cosine or parabolic shape) and the influence of the geomagnetic field. It also enables one to determine the half thickness of the layer. --M. R.

A-147 Becker, W. ; Ferraro, A. J. and Gibbons, J. J. , Coupling

and polarization computations approximated by a single discontinuity in the medium. Pennsylvania, State Univ. , Contract AF 19(604) -1304, Scientific Report No. 104, July 1, 1958.

33 p. 13 figs. , tables, 11 refs. , eqs. DWB--Following an

initial suggestion by one of the authors that coupling can be

approximated by considering slabs of uniform electron density around the coupling level, the problem has been further

simplified by employing a step discontinuity at the Nc level.

This gives a quick approximate method for computing the effect of coupling. Coupling is concentrated by appropriately

deforming the N-h and v-h curves in a region around the level

of Nc ; the deformation is done in such a manner that the gradient of electron density and collision frequency is zero as

one approaches the level of Nc from either below or above.

At this level there is, then, a step discontinuity in the N

and v profiles. W. K.B. solutions are used as the wave

functions and the coupling between the ordinary and extraordinary modes is taken into account by solving a boundary

value problem at the discontinuity. Formulas have been developed for the polarization of the upgoing back scattered

wave and the downgoing forward scattered wave. Results

are compared with those obtained by presumably more accurate methods Parkinson (1955). Even near critical coupling,

the approximation gives fairly satisfactory results for the

polarization of the Hmain" echo at 150 kc/s. --Authors' abstract.

A-148 Becker, Walter (Max-Planck-Inst. , Hannover, Germany),

Sporadic ionization of the E-region of the ionosphere above

Lindau/Harz during the past year. AGARDograph, Paris, No.

34:59-65, Sept. 1958. 3 figs. , 5 tables. DWB (629. 1323

N864a)-
45

The concept 'Sporadic Ionization of the E-Region" covers all

ionization steps between 60 and 190 km height that are sporadic in time and hence not due to normal ultraviolet solar

irradiation. A classification of these ionization steps is

adopted. It agrees with the proposals of the World-Wide

Soundings Committee as far as highly intense echo traces

are concerned. A statistical investigation of the characteristics of these traces is presented. The characteristics

were deduced from multi-frequency records taken at hourly

intervals from July I, 1957 to June 1, 1958. A well pronounced daily seasonal dependence of the maximum frequency of

the most significant Es trace on each record, with a clear

maximum at noon and summer, could be shown. The same

relationship was found for secondary Es traces which were

not mainly continuous. No distinct height ranges for the

different Es types or intense Es ionization steps, nor a daily-seasonal dependence of the heights could be found.

Homogeneous, layerlike reflections were observed mostly

about noon. Each second record showed such intense Es

reflections. Nothing new about the occurrence frequency

of weak meteoric traces could be found. Low level ionization steps below 85 km height only observed during daytime, with a winter maximum (rate of winter observations:

50%). It is assumed that different ionization mechanisms

must be responsible for the observed sporadic ionization

of the E-region. --Author's abstract.

A-149 Becker, Walter, Das Verqleichsverfahren der Station Lindau/

Harz zur Bestimmung der wahren Verteilunq der Elektronendichte in der Ionosphare . (Comparison method of the Lindau/

Harz station for determining the real distribution of electron

density in the ionosphere. ) Archiv der Elektrischen tJbertragung, Stuttgart, l3(2):49-57, Feb. 1959. 8 figs. , 2 tables,

25 eqs. , 5 refs. German and English summaries p. 49. DLC

—The principle of the method was described by the author in

an earlier paper in this periodical. In the meantime the method was considerably expanded, for by now all calculated and

observed ordinary echo sounding records of variable frequency are compared. The comparison of the extraordinary

sounding traces has also been included. The basic advantage of the last-named comparison is the fact that the extraordinary sounding trace is fully within the measuring range

of the customary ionospheric probes (1 to 16 Mc/s), while

formerly assumptions of some kind had to be made concerning the lacking ordinary trace between and 1 Mc/s. Greater

ease in height determination also results from a comparison

of the extraordinary traces. To allow the method to be adopted by other stations having a similar terrestrial magnetic inclination (67 6 '), the mathematical fundamentals, the re- quired tables, and a description of the evaluating device are given. -Author's abstract.
46

A-150 Becker, Walter (Max-Planck-Institut, fur Aeronomie), Die

allgemeinen Verfahren der Station Linau/Harz zur Bestimmung

der wahren Verteilung der Elektronendichte in der Ionosphare. (The general methods of the station Lindau/Harz for determining the electron density distribution in the ionosphere. ) Archiv

der Elektrischen Ubertragung, Stuttgart, 13(9):373-382, Sept.

1959. 9 figs. , 11 refs. , 27 eqs. German and English summaries p. 373. DLC--Three nonelectronic methods are described.

The "general method" is free of all restrictions. It is based

on the fact that with a terrestrial -magnetic inclination of 67

or more a purely longitudinal propagation can be assumed for

the extraordinary component so that Rydbeck's inversion for

purely longitudinal propagation can be applied. The two cor- rection methods intended for a reduction of the ordinary and

extraordinary sounding traces, respectively, depend in their

accuracy somewhat on the degree to which the observed shape

of the layer agrees with the profile of a reference layer to be

determined previously with the author's comparison method.

The two methods determine the corrections to be applied to

this reference profile for obtaining the unknown profile. In

their practical realization all three methods make use of the

slide rule principle. A 10-point N(h) analysis takes two

hours for the general method and I. 5 hours for each of the

correction methods. The accuracy of all three methods is

inherently greater than the practical measuring accuracy.

Their advantage over the present electronic methods resides

in the fact that they take also into account an extrapolation

of the sounding traces down to the abcissa origo f = and

f = fH, respectively, with the dependability of the comparison method. --Author's abstract.

A-151 Becker, W. (Max-Planck-Inst. fur Aeronomie, Lindau am

Harz, Germany), New methods and some results concerning

true ionospheric height calculations. Journal of Atmospheric

and Terrestrial Physics, N. Y. , 16(1/2): 67-83, Oct. 1959. 20

figs. , 2 tables, 10 refs. , 7 eqs. DWB, DLC--The methods

can be listed as follows: (a) Optical-graphical comparison

method, comparing, for certain layer-types, calculated ordinary and extraordinary h '(f) -traces with observed h'(f) records.

It is possible to determine the best fitting layer-types and its

parameters within 8 min. (b) General method, applicable to

any monotonic h' (f) trace. This method is based on Rydbeck's

solution of the respective integral equation. A 10 point h'(f)-

reduction according to this method takes 2 hr. (c) Correction

method, combining the methods (a) and (b). Thus the time

Necessary for a 10 point h '(f) -reduction can be reduced to 5/4

hr. The following results are reported: (a) Good agreement

between actual layer shape and parabolic N(h) -distribution

for the undisturbed night-time F-layer on Aug. 8, 1957. (b)
47

(b) Periodic movements (T^l hr, amplitude •%/ 8 km) of the

F-layer during a magnetically undisturbed night, 7-8 Aug.

1957. (c) Sudden ascent of the F-layer during a "Polar Sudden Commencement" ( a h ~ 60 km) within & hr on Sept. 15-

16, 1956. (d) Existence of an N(h) -minimum above the normal

E-layer above Lindau, Germany on Aug. 20, 1957, 1545 hrs.

—Author's abstract.

A-152 Becker, Walter, Die Bestimmung der wahren Verteilung der

Elektronendichte in der Ionosphare. (Determination of the true

distribution of electron density in the ionosphere. ) Archiv

der Elektrischen Ubertragung, 13(l):26-32, Jan., 1959. 6

figs. , table, 17 refs.--The methods known for determination

of electron density profiles as based on variable frequencies

of sounding were discussed in an earlier paper. Here is the

accuracy of the method discussed and all of them found completely uncertain.

// A-153 Beckmann, B. ; Menzel, W. and Vilbig, F. , Uber streuende

Reflexionen der Ionosphare. (The scattering reflexions of

the ionosphere. ) Germany. Forschungsanstalt der Deutschen

Reichspost, Mitteilungen, Band 4:45-50, 1939. 6 figs. , 3

eqs. DLC--Characteristics of the apparent periodic scattering in the E-region may be ionized clouds. In the F-region

characterized by vertical (and sharp) reflexion. Origin of

these clouds, irregularly distributed in 100-200 km is assumed to be an after effect of aurora borealis. --W. N.

// A-154 Beckmann, B. ; Menzel, W. and Vilbig, F. , Uber die praktische Bedeutung der Ionospharenforschung fur den Funkdienst.

(The practical significance of ionospheric research to the

radio service. ) Forschungs anstalt der Deutschen Reichspost,

Mitteilungen, 6:29-40, 1941. DLC--The several types of fading

are discussed separately accompanied by sample recordings

or graphs. Finally is summed up some countermeasures and

means whereby radio communication can be maintained or conditions for the communication predicted. --W. N.

A-155 Beckmann, B. , Erste Ergebnisse der Satellitenbeobachtung

fur die Kenntnis der Wellenausbreitung. (Initial results of

satellite observation contributing to the knowledge of wave

propagation.) Nachrichtentechnische Zeitschrift, 12(7):335-

343, July 1959. 23 figs. # 5 refs. --

A-156 Belgian Congo and Ruanda. Service Meteorologique. Ionosphere: publication mensuelle du Bureau de Geophysigue. (The

ionosphere: monthly publication of the Bureau of Geophysics.

)

Vol. 6, No. 12, Dec. 1957. 116 p. Almost entirely tables.

Data from Leopoldville, Binza, Elisabethville, Karavia, Bunia,

Ruampara. DWB (M10. 535 B429io)--
48

This publication gives data on ionospheric observations made

in the Belgian Congo at Leopoldville, Binza, Elisabethville,

Karavia, Bunia and Ruampara during Dec. 1957.

A-157 Bellchambers, W. H. (Royal Society Base, Halley Bay, Antarctica) and Piggott, W. R. (Radio Research Station, Ditton

Park, Slough, Bucks), Ionospheric measurements made at

Halley Bay. Nature, London, 182(4649): 1596-1597, Dec. 6,

1958. fig. , 2 refs. DWB-Some results of the ionospheric

measurements carried out in 1957 at the Royal Society Base

at Halley Bay are presented. Activity due to the incidence

orcorpuscular radiation reaches a maximum near 1400 L.M. T.

(30 W) and more than 2/3 of the examples are found between

0100 L. M. T. and 1000 L. M. T. The incidence oUxigh absorption is increased greatly at the equinoxes. The auroral radio

echo index at Halley Bay shows a similar diurnal variation

but shifted in phase toward the earlier hours. Consistent

recurrent diurnal changes in the F-layer are present; these

indicate that the station is favorably located for studying

regular variations of this layer at high altitudes. "The ionograms obtained near midnight in winter months show two

distance reflecting structures in the F-region; one which is

sequentially continuous with the F-layer of the previous day,

and the other, which usually first appears with the characteristic shape normally attributed to oblique reflexion from

a tilted layer, develops into the F-layer of the subsequent

day. The main features of the diurnal variation of the F-2

layer, critical frequency, foF2 indicates the following:

(1) the large diurnal variation of electron density in winter,

evident also in the total electron content of the layer, having a maximum near noon L. M. T. despite the absence of , significant photoionization due to solar radiation; (2) the

seasonal maxima of electron density in the day found at the

equinoxes, these are similar to those found at Port Luckroy

and Port Stanley; (3) small diurnal variation in electron density in summer showing a maximum near midnight L. M. T.

A-158 Bender, Hertwig K. , Erfahrunqen bei neueren Messnnaen der

atmospharischen Storungen des Funk-Empfangs vorzugsweise

auf 9 MHz. (Results of new measurements of atmospheric disturbances of radio reception, principally on 9 MHz. ) Germany,

Deutscher Wetterdienst in der US-Zone, Berichte, No. 12:161-

166, 1950. 6 figs. , 2 refs. MH-BH-Three methods of recording disturbances in wireless communication are described.

Diurnal variation of static and influence of thunderstorms and

fronts are discussed and a possible effect of penetrating cosmic rays considered. No connection was found with reflection or damping in the ionosphere. —C E. P. B.
49

A-159 Ben'kova, Natal 'ia Pavlovna, Mezhdunarodnyi geofizicheskii

god i iasledovaniia verkhnikh sloev atmoefery. (The International Geophysical Year and research in the upper layers of

the atmosphere. ) Moscow, Gosud. Izdatvo Literatury po Voprosam Sviazi i Radio, 1958. 47 p. 18 figs. , 12 refs. DWB

(M10. 53 B468me)—A general review of the IGY program is presented with a systematic discussion of investigations to be

carried out in the upper atmospheric layers which are closely

related to the propagation of short radio waves. These investigations will include: 1) vertical soundings of the ionosphere (ionospheric stations and their operation, 20 such stations in the U. S. S. R. ); 2) measurement of radio wave absorption in the ionosphere and of ionospheric winds and drifts;

3) study of atmospheric disturbances and geomagnetic variations; 4) studies of auroras and night sky glow; 5) investigations to be carried out with the aid of rockets and artificial

satellites in the U. S. S. R. A calendar of regular world days

and of world meteorological intervals is appended. —A. M. P.

A-160 Benner, Arthur H. , Predictingmaximum usable frequency

from long distance scatter. Institute of Radio Engineers,

Proceedings, 37(l):44-47, Jan., 1949. 5 figs., 4 refs. , eqs.

DLC--E-layers are responsible for the leading edge of the

echo, whereas maximum amplitude is returned from the ground.

On this basis, calculating the maximum frequency from time

delay of the scatter, provides method of prediction. --W. N.

A-161 Benner, Arthur H. , Second report on measurements of the

vertical incidence ionospheric absorption at 150 Kc/s. Pennsylvania. State College. Radio Propagation Laboratory,

Contract AF 19(122) -44, Basic Ionospheric Research* Technical Report, No. 13, June 20, 1950. 16 p. 14 figs. , 4 tables,

graphs, 18 refs. DWB--A direct continuation of the measurements of radio waves at vertical incidence at 150 Kc/s covering the period from July 1, 1949-Jan. 31, 1950. The data obtained are presented as diurnal plots of the' total absorption.

--W.N.

A-162 Benner, Arthur H. (Penna. St. Coll, Radio Propagation Lab.

)

Interim report "on lpng wave ionospheric absorption theory. Pennsylvania. State College. Radio Propagation Laboratory,

Contract AF 19(122) -44, Basic Ionospheric Research, Technical Report, No. 10, Jan. 20; 1950. 27 p. 32+ figs., 27

refs. , 41 eqs. DWB—As an initial step toward the explanation

of the causes and mechanism of ionospheric absorption of long

waves at vertical incidence- at 150 Kc/s, this theoretical attack is restricted to the special conditions at State College,

Penna. Based on the Appleton-Hartree dispersion equation,

expressions were obtained for the absorption coefficient for

various types of reflecting layers in the lower E region. --W. N.
50

A-163 Benner, Arthur H. , Vertical incidence ionospheric absorption at low frequencies . Pennsylvania. State College, Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic Ionospheric Research, Technical Report, No. 18, Jan. 15, 1951

(rev. Jan. 30, 1952). 84 p. 32 figs. , 5 tables, graphs, 22

refs. DWB—This study includes an examination of the complex index of refraction at frequency 150 Kc/s with the aid

of the Appleton-Hartree dispersion equation. The E layer

coefficient is obtained, the values of which are dependent

on the characteristics of the E region at maximum of ionization. Contributions of the deviating E and the non-deviating

D region are calculated as the total absorption, however it is tentatively concluded that the D region is not a pure electron layer; ions must be considered too. Data on typical

vertical incidence at 150 Kc/s from March 1949 through June

1950 are presented and analyzed for correlation with some

meteorological factors. Several conclusions and new problems pertinent to the subject are presented. A detailed description of the automatic measurement equipment is given.

--W.N.

A-164 Bennington, T. W. , Short-wave radio and the ionosphere.

With special reference to everyday professional and amateur

problems of short-wave transmission and reception. 2nd ed.

Wireless World, Iliffe and Sons, 1950. 138 p. 57 figs., 2

photos. GB-MO--While this book deals mainly with the

theory of radio transmission it has considerable interest for

meteorologists, including accounts of the formation and structure of the ionosphere, the technique of ionospheric measurements, regular and anomalous variations of height and ionization, radio noise and ionospheric storms, with relevant

curves and world charts. --C. E. P. B.

A-165 Bennington, T. W. , Propagation of v. h. f. via sporadic -E. Wireless World, 58:5, 1952. --Clouds of abnormally dense

ionization occuring within the normal E region can enable

waves of frequency up to 100 mc to be propagated over oblique paths. Temperate -zone -type records of sporadic-E

obtained by vertical -incidence measurements at Slough, Fraserburgh, De Bilt, Lindau, Freiburg, Domont and Poitiers are analyzed. It appears possible to trace the growth and

movement of these clouds from observations at a number of

stations.

A-166 Bennington, T. W. and Prechner, L. J. (both, B. B.C. ), The

B. B. C. ionospheric storm warning system. British Broadcasting Corporation, The B. B.C. Quarterly, 7(2), Summer 1952.

13 p. 9 figs. Abstracted from reprint. DWB—
51

The Ionosphere Section of the Engineering Information Dept.

of the British Broadcasting Corp. has issued warnings of imminent short period deviations from normal ionospheric characteristics from its Tatsfield Receiving Station since Sept.

1941. Forecasts are also issued regularly for internal use and

guidance in preparing warnings. Details of the warning system, accuracy of warnings, observational and collection work

of the B. B. C. 's Ionospheric Section, correlation with measurements of terrestrial magnetism, and with reception data

for North Atlantic circuits, annual and monthly frequency of

warnings (disturbances), duration of warnings (disturbances),

diurnal variation in start of warnings, correlation with sunspots, 27-day recurrence tendency of storms, elements forecast and accuracy of forecasts are all discussed in detail

and evaluated graphically. --M. R.

A-167 Bennington, T. W. , Critical frequency variations. Wireless

Engineer, London, 30(7): 175-179, July 1953. 8 figs. , 3 tables,

2 refs. DLC—Twelve-month running averages of critical frequencies for the F2 layer are plotted against twelve-month

running averages of sunspot numbers for two stations in the

Northern Hemisphere and two in the Southern Hemisphere, as well as for one station near the equator. It is found that,

whereas in the Northern Hemisphere there is a pronounced

tendency for the rate of increase of critical frequency to become smaller for the higher values of sunspot number, this

tendency is not evident in the Southern Hemisphere. Near

the equator the critical frequency behaviour lies between

that for the Northern and Southern Hemispheres respectively.

A suggestion is made that a 'saturation' effect may occur for

high values of sunspot number in the Northern Hemisphere at

the time of the annual minimum, which occurs in local summer, but not in the Southern Hemisphere where there are two

annual minima, one of which occurs in local winter. --Author's abstract.

A-168 Bennington, T. W. , Observations of the effects of ionospheric storms over a North Atlantic circuit. Journal of Atmospheric and Terrestrial Physics, 7(4/5): 235-243, Oct. 1955. 4

figs., table, 3 refs. DWB—The maximum usable frequency

(MUF) of the WWV signals from Washington received at Tatsfield, England, on 5, 10, 15 and 20 Mc/s were recorded in

July-Sept. 1953 in normal and disturbed periods and the diurnal variation of monthly medians extracted. The effect of

ionospheric disturbances is to depress the MUF by 10-50%,

the greatest reduction occurring between 7-11 h GMT, the

least between 12-23 h in summer, 12-20 h at equinox and 12-

17 h in winter. The disruptive effect depends also on the

value of the MUF at the time, being greater at night than by
52

day, especially in winter. Possible storm effects on the

lowest usable frequency (LUF) are briefly discussed.

--C. E. P. B.

A-169 Bennington, T. W. , Sporadic E and the F2 layer. Wireless

World, 65(6):262-263, June, 1959. 4 figs. , ref.

// A-170 Berg, Helimut, Bemerkungen zur Meteorologie der Ionosphare, (Remarks on meteorology of the ionosphere. ) Geofisica Pura

e Applicata, 19(1-2): 33-38, Jan. -March 1951. 3 figs. , table,

8 refs. German and English summaries p. 33. DLC--Daytime

echoes from the ionosphere were observed on the 80 m band

during the fall of 1942 at Cologne. Between Aug. 14 and Oct.

14, 1688 disturbances of the E layer and 1977 disturbances of

the F2 layer were observed with prevailing direction from the

NE in the E layer (in the F2 layer no noticeable favored direction was found) and speeds ranging from 10 to 370 m/sec

for E and F2 layers, respectively. Explanation of this movement is attempted, especially since it is not in agreement

with movements observed at night by HOFFMEISTER ('Leuchtstreifen" at 120 km), and are about 90 from direction of

winds at 10 km as observed from radiosonde ascents. --M. R.

A-171 Berg, Helimut, Tagung uber Physik der Ionosphare in Cambridge 6. - 9. September 1954. (Conference on Physics of the

Ionosphere in Cambridge, Sept. 6-9, 1954. ) Geofisica Pura

e Applicata, Milan, 29:230-233, Sept. /Dec. 1954. MH-BH--

About 40 papers delivered at an International Symposium on

Physics of the Ionosphere at Cambridge, Eng. are reviewed.

The papers are grouped around the following basic subjects:

1) the lowest ionospheric layers, 2) ionospheric disturbances

and ionospheric motion, 3) the F2-layer and 4) mathematical

problems of wave propagation in the ionosphere. --G. T.

A-172 Berg, Helimut, Zur Auswertung und Deutung von Aufnahmen

von Ionospharenstorungen nach der Impnls-Echo-Methode.

(Evaluation and interpretation of records of ionospheric disturbances obtained by the impulse echo method. ) Beitrage

zur Physik der Atmosphare, Frankfurt a. M. , 29(4): 276-289,

1957. 6 figs. , 2 tables, 10 refs. , eqs. German, English

and French summaries p. 276. DWB, DLC --By means of the

usual assumptions in the evaluation of records made by the

impulse echo method some conclusions can be drawn which

can be checked statistically. The statistical results do not

indicate that the very general considerations of PUTTER are realized as a rule. The actual scatter of the time vectors

(standard vector deviation) is computed as function of the

absolute value of the mean time vectors; these numbers are compared with the values to be expected theoretically.
53

If & is the observed scatter,^ A the scatter due to the errors

in reading off the data,<rp the scatter due to the distribution

of the end-points of the time vectors on PUTTER 's straight

line, and cr-r a turbulence scatter, then

The equation is poorly satisfied. The assumptions on which

it is based are stated precisely, and the question of their re- alization in nature is discussed. --Author's abstract.

A-173 Bergman, C. W. ; Macmillan, R. S. and Pickering, W. H.

(Calif. Inst, of Technology), A new technique for investigating; the ionosphere at low and very low radio frequencies.

(In: Boyd, R.L. F. ; Seaton, M. J. and Massey, H. S. W. , eds..

Rocket exploration of the upper atmosphere. London, Pergamon, 1954. p. 247-255. 9 figs. , 2 refs. ) DWB--A continuous wave phase measuring technique for ionospheric observations at low and very low frequency is described. The essential features of the system are: (1) a horizontal transmitting

antenna near the surface of the ground, which is resonant at

the operating frequency and which transmits no ground wave

in the direction of the receiver; and (2) a receiving station

located within line-of-sight of the transmitter at which the

phase of low frequency sky wave is directly compared with

a reference phase transmitted over a very high frequency

link. --Authors' abstract.

A-174 Berkner, L. V. and Wells, H. W. , Ionospheric research at

Watheroo Observatory. Western Australia, June 1938-June 1946;

Carnegie Institution of Washington, Publication No. 175, Vol.

13, 1948. 425 p. 29 figs. , 390 tables, 110 refs. DLC--

Detailed data on virtual height and critical frequencies of the

E and F-layers of the ionosphere are given and include a bibliography of 104 entries arranged by subjects. --W. N.

A-175 Berkner, L. V. (Carnegie Inst, of Wash. ), Signposts to

future ionospheric research. U. S. Air Force. Cambridge Research Center, Geophysical Research Papers, No. 12:13-20,

1952. DWB--A survey of the progress in ionospheric research

beginning with GAUSS a century ago, furthered by discoveries of MAXWELL and MARCONI and later by CHAPMAN, APPLETON, TUVE and others. The concept of the atmosphere as

a series of heat engines, developed by WULF, is extended to

include the F region as a fourth heat engine. Future efforts

should be along the lines of investigating chemical and photochemical problems, thermo-dynamic processes, atmospheric

movements, auroral physics, radio astronomy, and evolution

of the earth's atmosphere (and consequent evolution of life

on earth). --M. R.
54

A-176 Berning, Warren W. , Charge densities in the ionosphere from

radio Doppler data. Journal of Meteorology, 8(3):175-181, June

1951. 5 figs. , table, 6 refs. , 14 eqs. DWB--A brief description of the DOVAP (Doppler velocity and position) instrumentation and of the principles underlying its operation. The

theoretical principles underlying the determination of ionospheric structure from errors in DOVAP data reductions are discussed and an equation is developed which enables the determination of ionization densities from DOVAP records if the

true radial velocity of a missile is known along the trajectory. Numerical data on densities of the D, E, and F2 lay- ers are given. —I. L.D.

A-177 Berning, Warren W. (Ballistic Res. Labs., Aberdeen Proving

Ground, Md.), The determination of charge density in the ion- osphere by radio Doppler techniques. (In: Boyd, R.L.F. ; Seaton, M. J. and Massey, H. S. W. (eds.), Rocket exploration

of the upper atmosphere. London, Pergamon, 1954. p. 261-

273, 6 figs. , ref. , 20 eqs. ) DWB--In an earlier paper (BERNING, 1951), the author described a method whereby data from

the missile tracking system known as DOVAP could be used

to obtain equivalent electron densities in the ionosphere. In

the present work this theory is analyzed in slightly more detail to show the accuracy limitations in the method. To illustrate these limitations, a study is made of the ionospheric

structure for Dec. 15, 1952, which was obtained from DOVAP

tracking of a Naval Research Laboratory Viking rocket. It is

of interest to note that the vertical structure of a sporadic E

cloud is apparently obtained from the record. --Author's abstract.

A-178 Berning, Warren W. (Ballistic Research Labs. , Aberdeen

Proving Ground, Md. ), Ionospheric structure as determined

by a minimal artificial satellite. (In: Van Allen, James A.

(ed. ), Scientific uses of earth satellites. Ann Arbor, Univ.

of Michigan Press, 1956. p. 253-262. 3 figs. , ref., 13 eqs.)

DWB--A minimal artificial satellite is here defined as one of

such small size that internal equipment can consist of no more

than a small beacon used in the electronic tracking of the satellite. On the assumption that the beacon transmits a continuous wave, errors will be incurred in the tracking system data

whose magnitudes depend on the electron density in the ionosphere and on the frequency of transmission. The material contained herein briefly discusses the problems and develops the

analytical methods necessary for determining ionospheric electron densities from trajectory measurements. It is shown that a fairly detailed knowledge of the orbit permits determination

of equivalent electron density at the satellite as well as total

electron content below the satellite altitude. A small ambiguity
55

in the data may be largely removed by geometrical considerations or eliminated by the suitable placement of additional

ground receivers. --Author's abstract.

A-179 Berning, Warren W. , Earth satellite observations of the iono*

sphere. Institute of Radio Engineers, Proceedings, 47(280-288

Feb., 1959. 8 figs. , 10 refs. , 22 eqs. DLC-A number of so- called "First Generation" experiments for exploring the ionosphere with artificial earth satellite vehicles has either been

carried out or is planned by the United States and the Soviet

Union. The theoretical and experimental bases of these ex- periments are outlined and discussed, and their limitations

emphasized. The first available results are from the Soviet

experiments and these are discussed. Finally, a brief consideration is given to the kinds of satellite orbits desirable

for ionospheric experiments. --Author's abstract.

A-180 Best, Nolan R. ; Lowell, Robert; Mazur, Daniel G. and Uglow,

Kenneth M. , The AN/DKT-7( ) 15-Channel PPM Telemetering

transmitter. U. S. Naval Research Laboratory, NRL Report,

4016, June 16, 1952. 25 p. 18 figs,, 3 plates (fold. ), footrefs. DWB--Details are presented of a NRL design of a pulseposition modulation telemetering transmitter for use on medium sized rockets. It operates on 15 channels, weighs 18 lbs,

has dimensions 9 1/4 X 113/4 X 9 in. , and is contained in a pressurized core. Each of 15 channels is sampled 312. 5 times

a second, and 4 channels can be used to give a single channel with 1250 impulses a second. Flight calibrator, power

supply, control unit and a 227 Mc receiver for use with AN/

FKR-1 ground receiving and recording station are described as

auxiliary equipment. Tests in laboratory and field indicate

\% accuracy with use of calibrator and 2% accuracy with only

preflight calibration. —From authors' abstract.

A-181 Beynon, W. J. G. , Propagation of radio waves. Measurements

with oblique incidence on the ionosphere. Wireless Engineer,

Pt. B, 25(301) :322-330, Oct. 1948. 8 figs., 10 refs. -Deals

with some of the results of a series of oblique-incidence ionosphere experiments. Using pulse technique the maximumusable frequency of region F2 was measured over a transmission distance of 715 km in a direction approx. north-south.

The mean measured value agrees well with that calculated on

a simple theoretical basis from simultaneous normal -incidence

equivalent-height measurements made at the two ends of the

transmission path. In general, the upper frequency limit of

the oblique reflections from near the 100 km level (abnormal

E-region echoes) shows no close relationship with the corres- ponding normal-incidence observations. The mean value of a small number of measurements of the separation between the
56

oblique-penetration frequencies of the two magneto-ionic components is not markedly different from that measured at normal incidence at either end of the transmission path. The mean

seasonal variation of maximum-usable frequency factors has

been measured and compared with that calculated from normal

incidence data.

A-182 Beynon, W.J.G., Evidence of horizontal motion in region F2

ionization. Nature, London, 162(4127): 886, Dec. 4, 1948. 2

refs. DWB--During winters 1942 and 1943, relative field strength measurements were made at Slough (England) on signals

from the German short-wave sender Zeesen. In addition to re- gular sunrise ionospheric changes of large magnitudes in the

F2 layer, small irregularities were noted that suggest a rapid

east-west motion of or within the F2 region with an average

velocity of 430 km/hr. --G. J.E.

A-183 Beynon, W.J.G., Some notes on the absorption of radio waves

reflected from the ionosphere at oblique incidence. Institution

of Electrical Engineers, Proceedings, Pt. 3, 101(69): 15-20, Jan.

1954. 7 figs., 2 tables, 9 refs. DLC--The results of some oblique-incidence measurements on the ionospheric absorption

of radio waves are considered. For both short and very long

distances of transmission it is found that there is a marked

discrepancy between the observed values and the values calculated from simple theoretical formulas. The contribution of

multiple ionospheric reflections to the intensity of the received signal is briefly discussed. —Author's abstract.

A-184 Beynon, W. J. G. , The application of ionospheric data to

short wave transmission problems. Physical Society of London,

Proceedings, Sec. B, 63:145, 1950. (Summary only).--A short

survey is presented of the fundamental theory underlying the

application of normal incidence ionospheric data to short - wave communication problems, with particular reference to

calculating the maximum usable frequency (M. U. F. ). Some

aspects of the problem of applying normal incidence data on

ionospheric absorption to the calculation of field strength in

long distance transmission are also discussed.

A-185 Beynon, W. J.G. and Davies, K. , Simultaneous ionospheric

absorption measurements at widely separated stations . Journal of Atmospheric and Terrestrial Physics, 5(5/6): 273-289,

Nov. 1954. 10 figs., 3 tables, 6 refs. DWB--Comparison of

normal incidence 2Mc/s ionospheric absorption at Slough and

Swansea (230 km apart E-W) shows correlation of 0. 74 for

year (winter 0. 85, summer 0. 81). On about 6 Mc/s Slough

with Freiburg (400 km) gives 0.40, Swansea with Skelton

(330 km) 0. 68, Swansea with Allous (666 km) 0. 40. Correlation falls off with distance more rapidly in winter than in
57

summer. Some calculations are made oi monthly mean ionospheric absorption on 6 Mc/s. --C. E.P.B.

A-186 Beynon, W.J. G. and Thomas, L. (Dept. of Physics, Univ.

Coll. of Swansea), Travelling disturbances in region F2 and

magnetic activity. (In: Boyd, R.L. F. ; Seaton, M.J. and Massey, H.S.W. , eds., Rocket Exploration of the upper atmosphere. London, Pergamon, 1954. p. 131-132. fig., 3refs.)

DWB—An analysis of the results of a series of simultaneous

normal incidence ionospheric records made at Slough, Swansea, and Bangor is presented. The records show that the cor- responding large scale irregularities in the F2 layer can be

detected simultaneously. The results also show that the magnitude of the apparent velocity is closely correlated with the

magnetic disturbance and that there is a marked height gradient in the apparent horizontal motion in the F2 region.

A-187 Beynon, W.J.G. and Thomas, J. O. , The calculation of the

true heights of reflection of radio waves in the ionosphere.

Journal of Atmospheric and Terrestrial Physics, 9(4):184-200,

Oct. 1956. 17 figs., 24 refs., 17 eqs. DWB-Electron density in E, Fl and F2 layers is represented by a series of more

or less contiguous truncated parabolic sections. An expression is derived for the variations of virtual height with frequency, the parameters being calculated and shown in curves.

A numerical example is worked out, giving true height distribution calculated from observed cusp frequency, number of

electrons and calculated virtual heights for different wave

lengths compared with observed heights. --C. E.P.B.

A-188 Beynon, W.J.G. and Brown, G.M. (eds.), IGY instruction

manual: the ionosphere . International Geophysical Year,

1957/1958, Annals, Vol. 3, 1957. 1 vol. bd. in 2, continuously paged, illus., tables, refs., eqs. DWB—The ionosphere instruction manuals for IGY, 1957/58 are divided into 4 main parts or 2 volumes. Vol. I contains detailed instructions for vertical-incidence soundings (Pt. 1) and Vol.

II contains the other 3 parts and is devoted to absorption

measurements (Pt. II); drift measurements (Pt. Ill) and miscellaneous radio measurements (atmos. radio noise, whistlers, the dawn chorus, radio reflections from aurora or meteors and ionospheric scatter) Pt. IV. Not only instructions

but basic knowledge of each subject is covered. Pt. 1 was

prepared by the National Bureau of Standards at Boulder,

Colo. Each section contains several articles written by

authorities in the particular field. For listing of contents

see p. 636, May 1958, MAB. Articles separately abstracted. --M.R.

MH^^
58

A-189 Beynon, W.J.G. and Brown, G.M. (eds.), Miscellaneous

radio measurements . International Geophysical Year, 1957/

1958, Annals, 3(IGY Instruction Manual) :293-381, 1957. figs.,

tables, refs., eqs. Contents: Horner, F. : The measurement

of atmospheric radio noise, p. 295-314. Morgan, M.G. : Whistlers and dawn chorus, p. 315-336. Lovell, A.C.B. ; Forsyth, P. A. and Harang, L.: Radio reflections from aurorae. p. 337-341. Lovell, A. C.B. : Apparatus for radio-echo meteor

survey, p. 342-345. Bowles, K.L. : Ionospheric forward scat- ter, p. 346-360. Peterson, A.M.: Ionospheric back scatter, p. 361-381. DWB--This manual gives a thorough treatment of

all aspects of measurement of atmospheric radio noise (theory,

equipment, observation methods, collection of data in centers, etc.), sferics, tweeks, whistlers, the dawn chorus,

multiple whistlers, radio reflections from auroras, radio meteor surveys and ionospheric scatter (forward and backward)

for use in IGY program. Samples of observation forms and

records, and elegant photos of equipment are included. -- M.R.

A-190 Beynon, W.J.G. and Brown, G.M. (eds.), Measurement of

ionospheric drifts. International Geophysical Year, 1957/1958

Annals, 3(IGY Instruction Manual) :231 -287, 1957. figs., tables, refs., eqs. Contents: Briggs, B. H. : The determination

of ionospheric -drift velocities from three-receiver fading re- cords, p. 235-249. Huxley, L.G.H. and Greenhow, J.S. : The investigation of winds in the upper atmosphere by means

of drifting meteor trails, p. 250-274. Brief summary of other

techniques for measuring ionospheric drifts, p. 275-279. Some

comparisons of drift observations and techniques, p. 280-233.

References, p. 284-285. DWB--A complete and systematic

treatment of theory and practice of ionospheric drift measurement. Different methods (and the equipment analysis of re- cords and results obtained to date) are outlined. 3-receiver

fading technique, drifting meteor trail studies, coherent pulse

method, vertical incidence, ionogram comparison, radio star

observation, movement of noctilucent clouds, airglow luminosity changes, auroral drifts, etc. are described. Appendices

cover the symbols to be used in recording ionospheric drifts

and the IGY program is outlined. --M. R.

A-191 Beynon, W.J.G. and Goodwin, G.L., Horizontal drifts and

temperature in the lower part of region E . Journal of Atmospheric and Terrestrial Physics, 13(1/2): 180-182, Dec. 1958.

2 figs., 7 refs. DLC --Correlation between drift velocity and

temperature was experimentally determined at the Dept. of

Physics, Univ. College at Swansea. The pulse transmission

of about 2 Mc/s faded "slow" (0. 7 fades/min) and "fast" (9

fades/min). The results are discussed briefly. --W.K.
59

A-192 Beynon, W. J. G. and Brown, G.M., Geomagnetic distortion

of region-E. Journal of Atmospheric and Terrestrial Physics,

London, 14(1/2):138-166, April 1959. 21 figs., 34refs., 14

eqs. DLC--A detailed consideration of the behavior of the

normal E-region shows the existence of minor perturbations

from the classical Chapman theory. It is shown that some

of these differences can be ascribed to the influence of vertical drift of ionization resulting from the interaction of the

earth's magnetic field and the Sq

- current system flowing in

or near the E-layer. The resulting distortion of the electron

density profile of the E-layer is considered, with particular

reference to its effect on the values of the parameter f E at

different latitudes. The diurnal and seasonal changes in

the magnitude of the east-west component current are clearly reflected in the variations of f E, and an index n, measuring the sensitivity of the E-layer to seasonal changes,

shows marked singularities near the latitudes of the Sq-foci.

An analysis of conditions on magnetically disturbed days is

also given, and it is concluded that at temperate latitude

stations there is a depression in fE at times of magnetic disturbance comparable with the magnitude of that associated

with the vertical drift effect of the Sq

-current system at noon

in the summer. Reference is also made to conditions near

and within the auroral zone. Consideration of the effect of

sporadic E-ionization shows that this does not appear ser- eously to influence the tabulated values of fE. --Authors'

abstract.

A-193 Bhargava, B.N. (Kodaikanal, India), A new early-morning

ionospheric phenomenon. Nature, London, 170(4336): 983-984,

Dec. 6, 1952. fig., ref. DWB--On 60% of mornings ionospheric echoes ceased some minutes to several hours before sunrise and reappeared about ground sunrise at greater virtual

heights (300-500 km). --C. E. P. B.

A-194 Bhargava, B.N. (Kodaikanal Obs. , Kodaikanal), Observa- tions of spread echoes from the F layer over Kodaikanal: a preliminary study. Indian Journal of Meteorology and Geophysics, New Delhi, 9(l):35-40, Jan. 1958. 5 figs., 10 refs. DWB, DLC --Occurrence of spread F echoes at Kodaikanal for a period of about one year has been analyzed and diurnal and

seasonal characteristics have been found to exist in the frequency of occurrence of these echoes. It has been found

that the phenomenon occurs only during nighttime with largest frequency between 1900 and 1400 hrs local time. While

the seasonal variation is characterized by equinoctial max,

ima as in the case of geomagnetic activity, the day-to-day

variations in scattering indicate a negative correlation with

the degree of magnetic activity. Thus scattering persists
60

for largest percentage of time during comparatively quiet periods and is often altogether absent on magnetically stormy

nights. The phenomenon is discussed in relation to ionospheric irregularities and radio-star scintillation. --Author's abstract.

A-195 Bhargava, B.N. (Kodaikanal Obs . , Kodaikanal), Annual

wave in the world-wide F-reqion ionization. Indian Journal of

Meteorology and Geophysics, New Delhi, 10(l):69-72, Jan.

1959. 2 figs., 2 tables, 2 refs. DWB, DLC -An analysis of

squares of noon median F2 layer critical frequencies for a 3-

year period has been made in order to derive the latitude var- iation of the annual effect in the electron densities and its

relation to average F2 layer ionization. The results indicate

that the annual component R 1 varies with the latitude in a manner very nearly similar to that of the steady ionization

R0 and that for a given value of R for any latitude, Rl can

be derived approximately from a linear relationship of the

type Rl = 0.3 R0 - 4. 5. A similar analysis of 9-year data

for precise phase and amplitude of the annual component for a pair of stations yields a value of R 1, which is of the same

order of magnitude as R and which attains a maximum around

the epoch of minimum sun-earth distance. --Author's abstract.

A-196 Bhargava, B.N. and Gopala Rao, U.V., Ionospheric disturbances associated with magnetic storms at Kodaikanal. Indian Journal of Meteorology and Geophysics, Delhi, 10(2):203-

208, April 1959. 4 figs., table, 9 refs. DWB, DLC --F2 layer disturbances at Kodaikanal have been analyzed for a study

of the behavior of the critical frequency and the virtual height

during geomagnetic storms. The disturbances have been classified for this purpose into two categories, namely: the positive and negative. The characteristics of Dst and SD variation of f F2 and the Sn variation of h' F at night have been

discussed. The results have been explained in terms of the

quiet and disturbed day vertical drift velocities. --Authors'

abstract.

A-197 Bialecke, E.P. and Dougal, A. A. (both, Dept. of Electrical

Engin. , Univ. of Illinois), Pressure and temperature variation of the electron-ion recombination coefficient in nitrogen.

Journal of Geophysical Research, Wash., D. C, 63(3):539-

546, Sept. 1958. 4 figs., 11 refs. DLC --The electron-ion re- combination coefficient aei in ionized nitrogen gas is investigated as to its variation with pressure (0. 2 to 2 mm Hg) and

electron temperature (92 K to 300 K) corresponding to var- ious low electron energies. At 1. 3 mm Hg, ae i varies from

abou1^8. 5 X 10"7 cra3/sec at 300°K to 6. 7 X 10"6 cm3/sec

at 92 K, almost an order of magnitude difference. Discussion

of the possible modes of recombination in a nitrogen gas plasma
61

is given and dissociative recombination is found to be the

most probable means of electron loss. Microwave transmission methods were used in this study. --Authors' abstract.

A-198 Bibl, Klaus, L'ionisation de la couche E: sa mesure et sa

relation avec les eruptions solaires . (Ionization of the £ - layer: its measurement and relation to solar eruptions.)

Annates de Geophysique, 7(4) :208-2l4, 1951. 3 figs., table,

12 refs. French and English summaries. --Criteria for distinguishing between normal and abnormal layers are discussed. Relatively thin layers are classed as abnormal; their

ionization distribution corresponds to a power law with index > 2. A definition of foE is given which remains valid

for complex layers; foE is the highest critical frequency of a normal layer preceding or coinciding with the first discontinuity between the E and F echoes. Application of this

definition to the evaluation of ionosphere observations made

at Freiburg during 1950 and 1951 leads to greater Constance

of the daily variations and monthly means of foE. Examination of the values of foE for three summer months indicates

that all deviations > 0. 2 mc above the monthly mean are

attributable to sudden ionospheric disturbances.

A-199 Bibl, Klaus and Rawer, K., Les contributions des regions

D et E dans les mesures de 1' absorption ionosphericroe. (The

contributions of regions D and E in the measurements of ionospheric absorption.) Journal of Atmospheric and Terrestrial

Physics, London, 2(1): 51-65, 1951. 8 figs., 6 tables, 8 refs.,

9 eqs. English summary p. 51. MH-BH--Selective absorptions on frequencies 2 to 5. 6 MHz at Slough and Freiburg are used to calculate contributions of D and E layers 1949-1950

by a method which is set out in detail. Values usually attributed to D are found to be due partly to a fairly constant

contribution by E. This constant gives a number of collisions

in center of E layer in good accord with temperature and pressure at 125 km. «C . E. P. B.

A-200 Bibl, K. ; Busch, R. ; Rawer, K. and Suchy, K. , La nomenclature ionospherique et les conventions pour le depouillement . (Ionospheric nomenclature and conventions for evaluation. ) Journal of Atmospheric and Terrestrial Physics, 6(2/3):

69-87, March 1955. 7 figs., 22 refs. , 7 eqs. English summary p. 69. DWB--Proposals are made for classifying ionospheric "regions" and "layers". F region may be divided into

^1 1 $2> an intermediate layer Fl.5 which sometimes occurs

in tropics, and transitory layers. E region is divided into

E, Es and I (- E2 + E3). Definitions are given of fmin/ °ccultation frequency f a, critical frequency fc *nd top frequency

ft . Author also discusses very thin layers, magneto-ionic
62

components and virtual height. Annexes deal with intensity

of echoes, influence of transmitter characteristics, ionosphere characteristics and give a list of descriptive symbols.

--C. E. P. B.

A-201 Bibl, Klaus; Paul, A. and Rawer, K., Die Frequenzabhang- igkeit der ionospharischen absorption. (Frequency dependence

of ionospheric absorption. ) Journal of Atmospheric and Terrestrial Physics, N. Y., 16(3/4) :324-339, Nov. 1959. 12 figs,

table, llrefs., 8 eqs. DWB, DLC--Detailed analysis has

shown that in most cases where observations did not follow

the writers' old formula

L = B/(f + fL)

2

+ N -A 3 (f E/f)

intense echoes from a blanketing E-layer were present. The

theory is generalized to the case of a thin, mirror-like Es " layer embedded into a parabolic E-layer (model D). This

gives a new function depending on a second parameter given

by the altitude of the mirror. By application of the new formula (with the actual parameters of each observation) we obtain a much better description of the observed frequency variation. Noon values of B (non-deviative D-absorption) and N-

(deviative E-absorption) show opposed seasonal variations, N

increasing but B decreasing with the sun's height. The variation of N can be explained satisfactorily by a small decrease

of the altitude of the E-layer with increasing height of the sun.

—Authors' abstract.

A-202 Bibl, Klaus; Paul, Adolf and Rawer, Karl, Interpretation de

l'absorption ionospherique en fonction de la frequence. (Interpretation of ionospheric absorption with respect to frequency. ) Academie des Sciences, Paris, Comptes Rendus,

248(7) -.949-952, Feb. 16, 1959. table, Srefs., 5 eqs. DWB,

DLC --Elaboration of a new formula which explains the measurements relating to the reflection coefficient of the ionosphere

expressed with respect to the frequency f, through use of the

expression of the decrement of logarithmical absorption L.

This formula is written

L = 8 « + N A (17, v ) (f + fH) *

where fH ~ gyrofrequency, \/*i = reduced frequency of normal

E layer, B = non-deviative absorption mainly attributed to the

D region, N = deviative absorption in the E region. Seasonal

variation of N increases with the height of sun, whereas var- iation of B varies in the opposite direction. The seasonal

systematic variation is due rather to the deviative absorption

relating to the E region. --A. V.
63

A-203 Bibl, K. and Rawer, K. (both, Ionosphafren-Inst. Breisach,

Deutsche Bundespost, Ger. ), Traveling disturbances originating in the outer ionosphere.—Journal of Geophysical Research, Wash., D. C, 64(12): 2232-2238, Dec. 1959. 6 figs.,

13 refs. DLC--Some observations that have been obtained

with variations of the classical echo-sounding method must

be interpreted as resulting from perturbation and/or oscillation phenomena occurring in the outer ionosphere. The vertical velocity component of 'traveling disturbances' coming

from outside and propagating through the ionosphere is determined as 115 + 35 m/sec. Oscillation-like phenomena

have a large range of quasi-periods, between 1/4 and 12 hrs.

--Authors' abstract.

A-204 Bickel, John E. ; Heritage, J.L and Weisbrod, S., An ex- perimental measurement of VLF field strength as a function of

distance, using an aircraft. U. S. Navy Electronics Laboratory, San Diego, Calif. , Research and Development Report,

767; NEL Report 767, Jan. 28, 1957. 27 p. 29 figs., 9 refs.

DWB (M055 U585r)—Records and graphs show comparison of

daytime and nighttime very low frequency (VLF) transmission

conditions between ground transmitters near Seattle, Wash.

,

San Diego, Washington, D. C, etc. in 1954) and an airplane

operating at great distances from the station (to 7600 km).

Variations in reception conditions as the plane flies away

from or toward the transmitter are vividly depicted and their

causes analyzed. Height of reflection of sky waves, interference patterns, phase changes, etc. are interpreted in the

light of theory. The recorded curves fall within the general

range of the curves for ground wave and for 1, 2, 3, and 4

hop ionospheric reflection, but are far more irregular. Nomograms used in calculation of ionospheric -ground reflection for

10° -2200 km.

A-205 Bickel, John E. , A method for obtaining LF oblique-incidence

reflection coefficients and its application to 135. 6 Kc/s data

in the Alaskan area . Journal of Geophysical Research, 62(3):

373-381, Sept. 1957. 7 figs., 3 tables, 2 refs. DLC--Analysis of continuous recordings Aug. 9-Nov. 28, 1954 at Nome

and Kodiak. The reflection coefficient was obtained from the

ratio of the one-hop sky-wave to the calculated unabsorbed

one. Greater seasonal variation of daytime reflection coefficient (at 135 Kc/s ranged 0. 009 - 0. 032) occurred, and re- flection height was found more stable than at night. --W.N.

A-206 Bixby, L.H., Jr., Calculation of high frequency radio field

intensity over a 4000 km ionospheric path. Stanford University, Electronics Research Laboratories, Contract CST 10751,

Technical Report, May 1953.
64

A-207 Bixby, L. H. , Jr., Interpretation of WWV and WWVH signal

strength variations at Stanford. Stanford University, Electronics Research Laboratories, Contract CST 10751, Technical

Report, May 1956.

A 208 Bjelland, B. ; Holt, O. et al. (all, Norwegian Def. Res. Estab. Kjeller, Norway), The D region of the ionosphere. Nature, London, 184(4691) Supp. 13:973-974, Sept. 26, 1959.

3 figs. , 3 refs. DWB--A short note on two sets of observations made at Kjeller near Oslo and near Tromso7 in Norway.

At Kjeller measurements of ionospheric cross modulation

were made during March 1957-May 1958 by means of the pulse

technique. Some typical results from these observations are presented. A typical record sample from observations and re- sults from winter observations are graphically represented.

Observations iwere made during 1958 near Troms6/ of the D re- gion during disturbed conditions. Some results obtained from

the first short series of observations are discussed and graphically represented. --I. S.

A-209 Blackband, W. T. ; Burgess, B. ; Jones, I. L. and Lawson,

G. J. (all, Radio Dept. Royal Aircraft Estab. , Farnborough,

Hants), Deduction of ionospheric electron content from the

Faraday fading of signals from artificial earth satellites. Nature, London, 183(4669): 1172-1174, April 25, 1959. 2 figs.,

table, ref. DWB--Theie are two classes of fadings involved,

viz. (1) those due to change in energy flux at the receiving

aerial and (2) those accompanying a rotation of the plane of

polarization of this energy. The results of a method used to

interpret the fading records of Sputnik 1 and Sputnik 2 taken

at Farnborough and Cambridge show good agreement of the

values of electron content when compared with those deduced

from ionograms taken at Slough and Inverness. The method of

analysis discussed here is reliable. The results are shown

in a table and two graphs.

A-210 Blair, James C. , Frequency dependence of VHF ionospheric

scattering. U. S. National Bureau of Standards, NBS Report

No. 6049, March 20, 1959. 21 p. 35 figs., table, 9 refs.

DWB--This report contains data obtained by recording received

signal intensities simultaneously at 5 frequencies over the

1295 km path between the Long Branch transmitting station at

Long Branch, Illinois, and the receiving site at Boulder,

Colorado (Table Mesa field station. ) The data presented

here covers the period of Sept. 1, 1957 to June 30, 1958 (except for some later data on meteor burst and sudden ionospheric disturbances). Good simultaneous signal intensity

records were obtained for most of this period on 30, 40, 50

and 74 Mc. The available transmitter at 108 Mc was not
65

suitable for continuous reliable records prior to June 5, 1958.

In addition to the routine, 24-hour-a-day recording of average

received power, a set of high-speed records was made for 10-

minute intervals at different times during one day and analyzed for amplitude distribution and fading rate. Also, a low

sensitivity recording was made for the study of meteor bursts.

Data presented here show the measured results of frequency

dependence of average received power and illustrate how the

level of average received power is influenced by meteoric ionization, sporadic-E ionization, and ionospheric and magnetic

disturbances. A summary of hourly median and upper and

lower decile values on all frequencies is included, as well

as data on amplitude distributions and fading rates. --From

Author's introduction.

A-211 Blanchard, H. P. and Subbotin, B. T. , A system to measure

the polarization of obliquely-incident pulsed modulated signals. Stanford University, Electronics Research Laboratories

Contract W28-099-ac-157. Technical Report No. 6, Oct. 1951.

A-212 Blatt, E.L. ; Chaffee, D.C. and Vol z, C. , 75 Kc/s high power pulse transmitter. Pennsylvania. State Univ. Ionospheric

Research Lab. , Contract AF 19(604) -1304, Scientific Report,

No. 78, Oct. 30, 1955. 63 p. 33 figs., (incl. photos), eqs.

-•This report is essentially an extension of Scientific Report,

No. 40 and attempts to describe in some detail the conversion involved in changing the frequency of the Laboratory's

high power, long-wave pulse transmitter from 150 kc/s to 75

kc/s. Considerable detail is given with regard to automatic

circuitry which has been developed in order that the equipment may be operated continuously without the presence of

an operator. The report is concluded with a very brief description of a synchronizing transmitter, operating on a higher

frequency, which is utilized to trigger time bases, and other

apparatus, at the various remotely located receiving equipments. This permits recording the 75 kc/s ground pulse.

•-Authors' abstract.

A-213 Bolgianao, R., Jr. (Cornell Univ. , N. Y. ), Turbulent spectra in a stable stratified atmosphere. Journal of Geophysical

Research, Wash., D. C. , 64(12) :2226-2229, Dec. 1959. fig.,

6 refs., 14 eqs. DLC--After noting the discrepancy between

the predictions of turbulence theory and the empirical evidence

from radio experiments, the author suggests that this may be

the result of modification of the turbulent spectra by the effects of buoyancy in stably stratified layers. He points out

that in such situations kinetic energy of turbulence is converted, over a wide range of scales, to potential energy of

the resulting density deviations, that this potential energy
63

is subsequently destroyed by the action of further turbulent

mixing and molecular diffusion, and, finally, that the primary effect is to reduce the viscous dissipation arte significantly below that which normally would be estimated on the

basis of large-scale turbulent motions. Universal forms are predicted for the kinetic energy and density fluctuation spectra, and in the buoyancy sybrange (the part of the equilibrium

range that reflects the anisotropy induced by the density gradient) the energy spectrum is found to be proportional to

k-ll/5/ the density spectrum to k"7/5. --Author's abstract.

A-214 Bolle, A., Silleni, S. and Tiberio, C.A. , Registrazioni

ionosferiche. (Ionospheric records. ) Annali di Geofisica,

2(3): 377-38 7, July 1949. 11 figs. , table, 9 refs. , 12 eqs.

MH-BH--Forecast (made in Washington) and recorded (at

Rome) values of F2 perturbations are shown in numerous graphs

(Oct. 1948-Feb. 1949). Forecasts of critical ionospheric F2-

frequencies and perturbations made by the Central Radio Propagation Laboratory of the National Bureau of Standards (Washington) for period Sept. 1947-March 1949 are compared graphically with the values measured at Rome. --M. R.

A-215 Bolle, A. and Dominic i, P. , Contributo al calcolo dell as - sorbimento nella propagazione ionosferica delle onde corte.

(Contribution to the calculation of the absorption of the ionospheric propagation of short wave. ) Annali di Geofisica,

5(3):377-396, July 1952. 2 figs. , 7 refs. , 39 eqs. English

summary p. 396. MH-BH--The value for the coefficient of atmospheric attenuation for short waves, the absorption applying to the various ionospheric layers and to the various models of propagation of the waves have been calculated. --From

author's abstract.

A-216 Bonnet, G. ; Hunaerts, J. and Nicolet, M. , Analyse de resultats ionospheriques obtenus en Afrique lors de 1 'eclipse de

soleil du 25 fevrier 1952. (Analysis of ionospheric observations made in Africa during the solar eclipse of Feb. 25, 1952. ) Belgium. Institut Royal Meteorologique, Contributions, No. 38,

1957. 18 p. 9 figs. , 6 eqs. , 9 refs. DWB--Results of ionospheric observations made in Africa during the eclipse of Feb.

25, 1952 are coordinated and analyzed. E -region maxima were

formed by the same type of solar emission at each station, and

the recombination coefficient remained the same. The variable

parameter is the one which reflects the changes in the vertical

atmospheric structure at the geographic, or better still, the

geomagnetic equator, and those in higher latitudes. The particular aspects of coronal emission are explained. --A. V.
67

A-217 Booker, H. G., Ratcliffe, J. A., Shinn, D.H., Diffraction

from an irregular screen with applications to ionospheric problems . Royal Society of London, Philosophical transactions,

Ser. A, 242(856): 5 79-509, 12 Sept. 1950. 3 figs., 17 refs.,

54 eqs. DWB--Discusses the random fading of a radio wavefield reflected from the ionosphere. In Pt. I it is treated as Fresnel diffraction from a rough screen. In Pt. II the variations of the wave field due to a varying ionosphere are considered: first, on the basis of irregularities which have ran- dom velocities and second, from an irregular ionosphere moving with a steady velocity. --C. E. P. B.

A-218 Booker, Henry George (Cornell Univ. ), Application of the

magneto-ionic theory to radio waves incident obliquely upon

a horizontally-stratified ionosphere. U. S. Air Force, Cambridge Research Laboratories, Geophysical Research Papers,

No. 7:18-55, Dec. 1950. 14 figs. , 10 refs. , 107 eqs. DWB--

An algebraic quartic equation for the vertical component q

of the phase propagation vector can be used for the solution

of the problem. The roots of q are plotted as a function of

the electron-density N for fixed values of the wave frequency,

direction of earth's magnetic field and direction of incidence

upon the ionosphere. A simplified cubic equation is used

for computing limiting curves. Formulas for attenuation, lateral deviation, horizontal range and equivalent paths of magneto-ionically split wave-packets are derived. --A. A.

A-219 Booker, H. G. , On the level at which fading is imposed on

waves reflected vertically from the ionosphere . Journal of

Atmospheric and Terrestrial Physics, 7(6):343-344, Dec. 1955.

4 refs. DWB--The observed width of the autocorrelation function at lower frequencies is 6-7 times that given by theory.

Hence the level of the ionospheric irregularities causing fading is where the local wave length is 6-7 times X o. --C. E. P. R

A-220 Booker, H. G. ; Nichols, B. et al., Studies on propagation in

the ionosphere. Cornell Univ. School of Electrical Engineering, Contract DA 36-039-5c- 74903, Quarterly Progress Report,

No. 1, Dec, 31, 1957. 19 p. illus. -The advent of satellites

has made possible the determination of the height of scintillation by measurements made of radiation from a CW source at

various levels in the F region. A new attempt to explain

spread F, based on the idea of columns of ionization along

the earth's magnetic fields, has been made. —Authors' abstract.
68

A-221 Booker, Henry G. (Electrical Eng. , Cornell Univ. , Ithaca,

N. Y.), Phenomena of radio scattering in the ionosphere.

(IN: American Academy of Arts and Sciences, Atmospheric

explorations. Cambridge, M. I. T. , 1958. p. 101-125, 24

figs. , 35 refs. DLC (QC961 . A4) -The nature of the

ionosphere and VHF radar reflection records is reviewed and

illustrated and nine of the various scattering mechanisms and

phenomena explained: 1) fading of quiet echoes; 2) the "spread

F" phenomenon; 3) aspect- sensitive echoes; 4) twinkling of

point cosmic radio source noise; 5) long duration meteor trail

echoes; 6) echoes from below the E region; 7) VHF scatter

communication; 8) echoes from auroral ionization, and 9)

"sporadic E" phenomena. Many recorder records, graphs and

histograms vividly illustrate the nature of these phenomena.

The one factor which seems to be common to all of these an- omalous conditions in the various ionized media is turbulence, so it is hopes that explanations may be forthcoming

in terms of wave statistical turbulence theory.

A-222 Booker, Henry G. (Cornell Univ. , N.Y.), Radio-scattering

in the lower ionosphere. Journal of Geophysical Research,

Wash., D.C. , 64(12): 2164-2177, Dec. 1959. 10 figs. , 2 tables, 6 refs. , 33 eqs. DLC --Radio-scattering phenomena at

the 80- to 90-km level observed in the frequency range 30 to

100 Mc/sec indicate the presence of irregularities of electron

density with scales in the range from 20 to 60 meters (corrugation wave-lengths from 120 to 360 meters). The irregularities are approximately isotropic, and scattered power is inversely proportional to about the sixth power of scale. The

power law involved may, however, vary somewhat with the

state of the atmosphere. The fading of the radio waves is

consistent with random motions of the irregularities with velocities of the order of 25 m/sec. Similar observations of the

sporadic -E phenomena occurring at a height of about 110 km

show that the scattered power is inversely proportional to

something like the eighteenth power of scale while the velocity of irregularities, if interpreted as random, is around 5

m/sec. --Author's abstract.

A-223 Bornholdt, John W. and Jackson, Thomas T. (Pa. St. Coll.

Io. Res. Lab. ), Oblique incidence measurements at 150 Kc/s . Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic Ionospheric Research,

Technical Report, No. 21, March 30, 1951. 71 p. 47 figs. , 9 refs. DWB--Results of measurements of 150 Kc/s pulse

signals ar ranges from 25 kilometers to 180 kilometers are described. A short description of receiving and transmitting

equipment is given, followed by a detailed account of methods

of data analysis. Data presented includes virtual height and
69

reflection coefficient as a function of range and time, and

polarization ellipse specifications as a function of range,

time and azimuth. A short study of the fine structure of the

lower ionosphere is given, including pulse shape variations

and a chart and photographs of "D -layer" echoes. The report

is concluded with a section of data interpretation and recommendations for future work. --Authors' abstract.

A-224 Bossolasco, Mario and Masotto, Antonio, La constituzione

dell'-alta atmosfera e la Stazione Ionosferica dell'Istituto

Geofisico di Genova. (The constitution of the upper atmosphere and the Ionospheric Station of the Geophysical Institute of Genoa. ) Geofisica e Meteorologia, Genoa, 2(5/6):

80-86, Sept. /Dec. 1954. 4 figs. , 2 eqs. DWB-The physical and chemical characteristics of the ionosphere, its role

in radio transmission, the electrical density of its various

layers, and its ionization phenomena are reviewed and the

ionospheric station of the Geophysics Institute of the University of Genoa is described with the aid of a diagram.

--I.L.D.

A-225 Bossolasco, M. and Elena, A. (both, Inst. Geof. Geod.

Univ. Genoa, Italy), On some characteristics of the E-layer%

Planetary and Space Science, N. Y. , 1(3):205-212, Aug. 1959.

3 figs. , 10 refs. DWB--Some aspects of the dependence of

the Es -ionization on the geomagnetic field are derived, further, an attempt is made to deduce the mean world-wide drift

direction of Es in summer, using the time displacement that

occurs for the daily maxima of the hourly median values of

f Es . --Authors' abstract.

A-226 Boston University. Upper atmosphere Research Laboratory,

Investigation of the ionosphere utilizing sounding rockets.

Contract AF 19(122) -36, Progress Reports, No. 9 and No. 12,

Oct. 24, 1951 and June 30, 1952. two pieces, photos, graphs,

diagrs. , ref. DWB--Report No. 9--June 1-Aug. 31, 1951: Preparations were made for Aerobee ascent of Aug. 7, 1951. Previously obtained rocket data are being put on IBM cards. The

rocket reached 52 mi, just short of the E layer which was determined to be at 60 mi at that time. Recovery of equipment

was satisfactory and some of it can be easily prepared for the

Oct. 1951 firing. Photographs of equipment before and after

firing are included. A television spectroscope has been constructed and preliminary results obtained. Report No. 12--

March 1-May 30, 1952: Brief report on firing on April 22, 1952

of Aerobee No. 24 which carried similar instrumentation to

Aerobee No. 20 described in Report No. 10. Maximum altitude

70 mi at 180 sec. Some damage occurred to equipment but data

were all usable and will be computed in connection with oblique incidence propagation studies. --M. R.
70

A-227 Bouchard, Jean, Sur la propagation ionospherique des ondes

decametriques dans les regions polaires arctiques. (On ionospheric propagation of lOcmwaves in the Arctic.) Academie

des Sciences, Paris, Comptes Rendus, 236(2): 220-222, Jan.

12, 1953. DLC —Systematic study of the propagation of 10 A

waves over great distance shows the influence of ionic disturbances in the Arctic, connected with magnetic disturbances.

The signals received at Dijon, France, from the region of the

North Pacific (NE Siberia, Alaska, British Columbia, the Pacific Northwest and Hawaii) are distorted when passing through

the belt of maximum auroral activity during magnetic storms but

signals from other parts of the Pacific (Japan, Mariannes, New

Zealand, etc. ) are not thus distorted, except when taking secondary paths traversing these disturbed zones. --M. R.

A-228 Bourdeau, R.E. , Whipple, E.G. and Clark, J. F. , Analytic

and experimental electrical conductivity between the stratosphere and the ionosphere. Journal of Geophysical Research,

64(10) :1363- 1370, Oct. 1959. 4 figs. , 29refs., 13 eqs.

A-229 Bowe, P. W. A. (Cavendish Lab. , Cambridge), A study of in- dividual radio atmospherics received simultaneously at two

places. Philosophical Magazine, London, 44(355) :833-840,

Aug. 1953. 4 figs. , 3 tables, 4 refs. DWB--A previous paper

(BOWE 1951) described a method of studying the propagation of

radio waves of frequency 2 kc/s to 10 kc/s over the surface of

the earth, by observing the responses of narrow-band receivers to individual radio atmospherics. The present paper describes an extension of these observations in which the same

method was used simultaneously at two places, Cambridge and

Aberdeen, 550 km apart. The narrow band receivers at both

places were tuned to frequencies 7. 5, 5. 0, 3. 5 and 0. 6 kc/s.

By comparing the responses at the two places, the attenuation

factors for each frequency could be found. The sources of the

atmospherics were located by the 'Sferic' direction finding system of the Meteorological Office, supplemented by a direction

finder at Cambridge. Most of the observations were made at

about noon. The results are presented as tables giving the

propagation factor for 1000 km path, for the four frequencies

studied. It was found that waves of frequency 0. 5 kc/s are less attenuated than waves of frequency 3. 5 kc/s. The re- sults for 7. 5 and 5. kc/s appear to indicate that the attenuation is less in winter than in summer. --Author's abstract.

A-230 Bowhill, S. A. , The fading of radio waves of frequencies between 16 and 2400 kc/s. Journal of Atmospheric and Terrestrial Physics, 8(3):129-145, March 1956. 14 figs. , 2 tables,

13 refs. , 11 eqs. DWB--
71

The lowest ionosphere, which reflects low frequency radio

waves, contains irregularities which cause fading of these

frequencies. These have been studied by 3 types of experiment at Cambridge, Eng. , using nearly vertical incidence at

night. The range 16-200 kc/s shows shallow fading with a quasi-period of 7 min up to 70 kc/s, above this a quasi-period

of about 1 min appears as well, increasing until it dominates

the slower fading. Two receivers tuned to 85 kc/s separated

by various distances gave fading records indicating structure

sizes at the ground of 5 km for the slow fading and 1 km for

the fast fading. Thirdly, records at 3 receivers at right angles on 70 kc/s show that the slow fading is due mainly to

random velocities of about 40 m/s, with a much smaller drift

velocity varying irregularly from an average of 20 m/s to NNE

at 0130 to 17 m/s to ENE at 1930. A suggested model of irregularities in the D region at night is shown. —C. E. P. B. and

author's abstract.

A-231 Bowhill, S. A. , Ionospheric irregularities causing random fad- ing of very low frequencies. Journal of Atmospheric and Terrestrial Physics, U(2):9l-I01, 1957. 11 figs. , 2 tables, I3refs.

DWB--The process by which random irregularities in the ionosphere cause random fading in a reflected radio wave at the

ground may be divided into two parts: the scattering process

within the layer which builds up an inhomogeneous field in

free space immediately beneath it, and the diffraction process

by which this field propagates to the earth's surface, possibly changing in form as it travels. The extent of this change is

evaluated by finding the correlation coefficients for three pairs

of quantities measured experimentally at 75 and 150 kc/s frequency. These are (a) the signal amplitude at two horizontally separated receivers, (b) the amplitudes of the first and second reflections (c) the amplitude and phase of the first reflection. The diffractive changes are found to be considerable,

but the wave emerging from the layer is probably modulated in

phase rather than amplitude. A study of the variation of fading speed at 75 kc/s with height of reflection appears to confirm existing ideas concerning the presence of small-scale irregularities above a critical height in the lower E-region.

--Author's abstract.

A-232 Bowhill, S. A. , Ionosphere absorption pulse method. Pennsylvania. State Univ. Ionosphere Research Lab. , Report, Sept.

30, 1957.

A-233 Bowhill, S. A. , The Faraday-rotation rate of a satellite radio

signal. Journal of Atmospheric and Terrestrial Physics, 13(1/2):

175-176, Dec. 1958. fig., ref.DLC--The recorder time constant

must be <C 1/16 of the mean fading period T2 of the fading function, if the deduced fading speed is to be correct within 5%.
72

A-234 Bowles, K.L. , Observation of vertical-incidence scatter

from the ionosphere. Physical Review Letters, l(12):454-455,

Dec. 15, 1958. 2 figs. , table, 4 refs. --Experimental verification of the existence of incoherent or semi-incoherent scatter

by free electrons was made Oct. 21 and 22, 1958 during daylight hours. "A" scope photographs are shown. --W. N.

A-235 Bracewell, R. N. , The propagation of very long radio waves . Institution of Electrical Engineers, Journal, Pt. 3, 95(37) :326,

Sept. 1948. --Summarized report on the work in progress at Cavendish Laboratory. Observed fluctuations are consistent with

horizontally moving ionospheric inhomogenities. --W. N.

A-236 Bracewell, R. N. , The ionospheric propagation of radio waves

of frequency 16 kc/s over distance of about 200 km. Institution of Electrical Engineers, Proceedings, Pt. 4, 99(3):217-22§

July 1952. 16 figs., 11 refs. DBS- Digest version: Ibid. , Pt.

3, 99(60)217-221, July 1952. 6 figs. , 11 refs. DLC-Features

an experimental technique of phase measurement achieved by

comparison with a reference signal from transmitter to receiver by land line. It is an extended investigation of 16 kc/s

waves over 90 km that began in 1946 and gives results of the

experiments carried out at distances up to 200 km. --W. N.

A-237 Bracewell, R. N. , Theory of formation of an ionospheric layer

below E layer based on eclipse and solar flare effects at 16

kc/sec. Journal of Atmospheric and Terrestrial Physics, London, 2(4):226-235, 1952. 4 figs, , 13 refs. , eqs. MH-BH,

DWB--The CHAPMAN theory of the ionosphere indicates that a decrease in the incident radiation should have little effect

on height of reflection. This was tested during partial solar

eclipse of April 28, 1949, at Cambridge, England, on 16 kc/

sec transmission from Rugby, and a symmetrical anomaly of

about I km was found. A new theory is presented in which the

condition, that electron density is negligible compared with

ionizable particles, is removed. This agrees with the eclipse

observations; the ionizing radiation originates regularly over

the sun's disk and not specially in active regions. --C. E. P. B.

A-238 Bracewell, R.N. and Bain, W.C., An explanation of radio

propagation at 16 kc/sec in terms of two layers below E layer . Journal of Atmospheric and Terrestrial Physics, 2(4):216-225,

1952. 5 figs. , 18 refs. MH-BH, DWB--Observations of 16 kc/

sec transmission from Rugby at Cambridge (90 km) and Aberdeen (535 km) indicate two distinct superposed banks of ionization provisionally named D $ and D/S . Heights uncertain

but probably about 70 + 8 km at noon and 15-18 km higher at

night, with a sharp change around sunrise and sunset.

--C.E.P.B.
73

A-239 Bracewell, R.N., Analogues of an ionized medium. Applications to the ionosphere . Wireless Engineer, London, 31(12):

320-326, Dec. 1954. 12 figs. , 2 tables, 2 refs. , 24 eqs.

DLC--A continuous transmission line with series impedance

and shunt admittance is compared with a representation of

linearly polarized plane waves, first in nonionized free space

and then in an ionized medium. Effect of collisions between

an electron and positive ions or neutral molecules is equivalent to a mechanical impedance on its motion. Cases of inhomogeneous media are next dealt with and the mechanical

analog of a flexible spring strip is introduced. Finally, a

partial analogy is drawn between a plane wave in an ionized

medium and a wave in a wave guide. --C.E. P.B.

A-240 Bracewell, R . N . ; Harwood, J. and Straker, T. W. , The ionospheric propagation of radio waves of frequency 30-65 kc/s

over short distances. Institution of Electrical Engineers, London, Proceedings, Pt. IV, 101(6) :154-162, Feb. 1954. 12 figs.

,

13 refs. (Same article, digest version). Ibid., Pt. Ill, 101(70):

108-110, March 1954. 4 figs. , 13 refs. DLC--The paper describes experiments carried out at Cambridge on waves of frequency 30-65 Kc/s reflected from the ionosphere at steep incidence. The phases and amplitudes of two linearly polarized

components of the downcoming wave were measured with re- ference to the ground wave. The results for frequencies of

30, 43 and 65 kc/s are considered in turn, and compared with

the results for 16 kc/s. The main conclusions were as follows:

(a) The day-to-day variations of the downcoming wave were

greater at the higher frequencies, (b) The change of height of

reflection in passing from day to night was about the same for

all the frequencies, (c) In summer, the amplitude by day and

by night was very different, except at 16 kc/s. (d) The polarization at all the frequencies was approximately circular, lefthand and constant. The height of reflection of waves of frequency 30 kc/s was determined by using the frequency/change

method of APPLETON and BARNETT. -Authors' abstract.

A-241 Bramley, E. N. , Direction-finding studies of large-scale ionospheric irregularities. Royal Society of London, Proceedings,

Ser. A, 220(1140) :39-61, Oct. 22, 1953. 12 figs. , 4 tables,

17 refs. , eqs. DLC—Directional measurements on pulse signals of 2-15 Mc/s in Britain, reflected from ionosphere at vertical and oblique incidence, are interpreted in terms of ionospheric tilts. Some measurements point to drifting clouds of

ionization in Es layer. In the F layer ripples in surface of constant ionization density are found, wave length 50-400 km

(peak 150 km), vertical amplitude increasing with wave length

to 7 km, speed up to 350 m/s (peak at 150 m/s). They mostly

move W-E before 14 h UT, E-W after 14 h, due to a clockwise

rotation.—C.E. P.B.
74

A-242 Bramley, E. N. , The diffraction of waves by an irregular re- fracting medium. Royal Society, Proceedings, A, 225:515-

518, 1954. --A method is described of calculating the diffraction effects produced by a thick stratum of an irregular refracting medium. It consists of evaluating the statistics of the

phase irregularities in the wave-front after traversing the medium, and treating these irregularities as having been produced

by a thin phase-changing screen. For a particular statistical

model of the irregularities in the medium the result is shown

to be identical with that obtained by Fejer using a different

method.

A-243 Bramley, E. N. , Some aspects of the rapid directional fluctuations of short radio waves reflected at the ionosphere. Institution of Electrical Engineers, London, Proceedings, Pt. B, 102

(4):533-540, July 1955. fig, 2 tables, 48 eqs. DWB--Measurements have been made of the rapid directional fluctuations observed on single -component first-order ionospheric echoes, at

vertical and oblique incidence (range 700 km), and on frequencies of 2. 5-10. 5 Mc/a Under quiet ionospheric conditions

the r. m. s. angular deviations are of the order of 1 or less,

but they are appreciably greater under ionospheric -storm or spread- F conditions. The fluctuations are uncorrelated at an

interval of five sec. It is shown that a layer of irregular ionization-density within region E would account for the quiet condition F layer results, and this would require random variations

of the phase path through the region of the order of only 3 m at

a frequency of 5 Mc/s. The E layer results appear to be affected by partial reflections at different levels within the re- gion. Appendix gives Theory of rapid directional fluctuations

produced by ionospheric irregularities. --Author's abstract.

A-244 Bramley, E. N. , Some comparative directional measurements

on short radio waves over different transmission paths. Institution of Electrical Engineers, London, Proceedings, Pt. B,

102(4): 544-549, July 1955. 3 figs. , 2 tables, 6 refs. , 16 eqs.

DWB--From observations of transmissions on 5-8 Mc/s from

Aberdeen to Winkfield, entirely over land, and Hemsby, mainly over sea, it is concluded that correlation of closely corres- ponding components of F layer tilt is generally negligible. A

daily variation of tilt approximately E-W occurs at about 0. 2

/h. On second order F layer transmissions over 700 km, the

land acts as a rougher reflector increasing the rapid directional fluctuations of the echo but not the total bearing variance,

mainly caused by ionospheric tilts. --C. E. P. B.
75

A-245 Bramley, E.N., Directional observations on H. F. transmissions over 2100 KM. Institution of Electrical Engineers, London, Proceedings, Pt. B, 103(9): 295-300, May 1956. 5 figs.

,

3 tables, 5 refs. Also review of above article, entitled Ionospheric reflection of H. F. waves, in Institution of Electrical

Engineers, London, Journal, n. s. , 2(17): 282 -283, May 1956.

2 figs. DLC--Previous studies showed that directional fluctuations in receipt of pulsed short wave signals from a distance of 700 km were due to ionospheric irregularities. An

extension of this work to a distance of 2120 km at 5 and 11 Mc/s showed that rapid fluctuations were larger than at 700

km (especially at night on 5 Mc/s) and were unaffected by

ionospheric or magnetic storms. Experiments were carried

out from Dec. 1952 to Oct. 1954 between Malta and Winkfield, Berkshire. Fluctuations about mean were within + 1 for IF and +_ 2 for 2F echoes, and for IF echo individual

bearings had a s. d. of 0.8 about the mean which was within

0. 2 of the correct bearing. --M. R.

A-246 Bray, W. J. ; Hopkins, H. G. ; Kitchen, F. A. and Saxton, J. A.

,

Review of long-distance of radio-wave propagation above 30

Mc/s. Institution of Electrical Engineers, London, Proceedings, Pt. B, 102(1) :87-95, Jan. 1955. 3 tables, 61 refs. DLC--

The purpose of the paper is to summarize the present state of

knowledge concerning the factors affecting long-distance radio

wave propagation at frequencies above 30 Mc/s. Attention is

drawn to various ionospheric and tropospheric propagation mechanisms and their broad characteristics. The account of these

special processes is preceded by Sections dealing with selected aspects of "normal" propagation. A comprehensive bibliography is included. --Authors' abstract.

A-247 Breit, G. and Tuve, M. A. , A test of the existence of the

conducting layer. Physical Review, 28(3): 554-575, Sept. 1926.

11 figs. , table, foot -refs. , 20 eqs. DLC--(l) Groups of radio

waves arrive at the receiving station separated from their echoes. This shows that the hypothesis of an ionized layer of

the atmosphere is correct. (2) The retardation is such as though the layer were at a height of from 50 to 130 miles. The

apparent height is greater in the fall than in the summer for

70-meter waves with an 8-mile base. (3) Radio fading is present for reflections alone quite independently of interference

between the ground and the reflected waves. (4) A quantitative discussion of the possibilities of refraction shows that

in most cases the increase of electronic density must be more

sudden and discontinuous than that given by a density proportional to the square of the height or else that not all of the

possible states of polarization of the waves in the upper atmosphere are present. --From authors' abstract.
76

A-248 Breit, G., Group-velocity and long ret&rdationg of radio

echoes. Institute of Radio Engineers, Proceedings, 17(9):

1508-1512, Sept. 1929. 2 figs. , table, 3 refs. , 5 eqs. DLC--

Up to 15 sec retardations of echoes have been observed by

STORMER and by VAN DER POL. VAN DER POL's theory

that group-velocity may account for STORMER *s long retardation observation is discussed. Author suggests that STORM - ER's and VAN DER POL's observations were splashes of the

very same echo focused accidentally on a favorable patch of

ground.

A-249 Breit, G., The significance of observations of the phase of

radio echoes . Institute of Radio Engineers, Proceedings,

17(10): 1815-1821, Oct. 1929. 8 refs. , 14 eqs. DLC--The method of observing echoes, developed by TUVE and HAFSTAD, is

discussed in order to show to what extent the phase can be

expected to be constant throughout the echo if the frequencydispersion of the K-H layer is taken into account.

A-250 Bremmer, H. , Mode expansion in the low-frequency range for

propagation through a curved stratified atmosphere . U. S.

National Bureau of Standards, Journal of Research, Sec. D,

63(l):75-85, July/Aug. , 1959. 6 refs. , 40 eqs. DLC, DWB--

The influence of the earth accountable for by an approximate

boundary condition at the surface of the earth, the problem is

reduced to that of the other medium only for which the coefficients of the mode expansion are derived taking into account

earth's curvature. The expansion to be derived is wanted in

particular when studying the influence of gradual transition in

the electron density with height at the lower edge of the ionosphere. --From author's abstract.

A-251 Brennan, D.G. and Phillips, M.L., Phase and amplitude var- iability in medium-frequency ionospheric transmission. MIT

Lincoln Laboratory Tech. Rpt. 93, Sept. 16, 1957.

A-252 Brice, N.M. (Univ. Queensland, Brisbane), Variations in

ionospheric F-region characteristics. Australian Journal of

Physics, Melbourne, 11(4):487-591, Dec. 1958. fig., table,

6 refs. DLC --Day and night curves were computed from some

Macquarie Island (geomagn. lat. 60 S, local magn. dip angle

78 ) h'f records taken since 1950. They are assumed to be

the first high southern latitude (N, h) profiles calculated and

are presented here along with some derived parameters. The

hmax and Nmax refer to the height and electron density at

maximum ionization level, and the sunspot maximum and minimum to corresponding observation of activities. The curves

aid those working on the theory of the quiet ionosphere, and

favor King's statement about the meaningless of hp F2 day

presence.
77

A-253 Brice, N. M. , Note on short range echoes on ionospheric

recorders . Journal of Atmospheric and Terrestrial Physics,

13(1/2):179, Dec. 1958. 4 re£s.--Very brief note in favor of

Dowden's findings that absence of night echoes may be instrumental and that they may be back scattering from sea

waves. Decreased E and F echoes corresponded to increase

of sea echo strength during a 1957 expedition to Macquarie

Island. -W.N.

A-254 Brice, P. J. ; Evans, G. O. ; Packer, E. J. and Henbrey, R. S.

,

North Atlantic scatter circuits. Great Britain, Post Office,

Engineering Dept. , Radio Branch, Radio Report, No. 2652,

March 24, 1959. 8 p. 8 figs. , 3 tables.

A-255 Briggs, B. H. and Phillips, G.J. , Study of horizontal irregularities of ionosphere. Physical Society, Proceedings, Sec. B,

63(371): 907 -923, Nov. 1, 1950. -Theory of diffraction by ran- dom screen as developed by H. G. Booker, J. A. Ratcliffe

and D. H. Shinn is presented in convenient form for practical

application in ionospheric experiments; measurements of cor- relation of fading of reflected electromagnetic wave at spaced

receiving points can be used to find extent of angular spreading of downcoming wave.

A-256 Briggs, B.H. , Phillips, G.J. and Shinn, D.H. , The analysis

of observations on spaced receivers of the fading of radio signals. Physical Society of London, Proceedings, Sec. B, 63(2):

106-121, Feb. 1950. 8 figs., 5 refs. DLC -Authors point out

that fading may be due to drift of a diffraction pattern past a

receiver, or to irregular variations in the pattern or both operating a simultaneously. Steady velocity of the drift and rate

at which the pattern alters as it moves may be calculated by

taking observations at three points at the corners of a rightangled triangle. --G. J.E.

A-257 Briggs, B. H. , An investigation of certain properties of the

ionosphere by means of a rapid frequency-change experiments.

Physical Society, Proceedings, London, Pt. 3, 64(375 B):255-

274, March 1, 1951. 12 figs. , 22 refs. DWB--"Irregularities of

ionization are sometimes found to be localized in height. Observations of the reflection coefficient of the abnormal E-region

suggest that there are two distinct types of region, one an irregular region consisting of scattering clouds, the other a co- herent layer with a thickness of the order of 5 km. "--From author's abstract.
78

A-258 Briggs, B. H. , The determination of the collision frequency

of electrons in the ionosphere from observations of the reflec - tion coefficient of the abnormal E layer. Journal of Atmospheric and Terrestrial Physics, 1(5/6) :345-348, 1951. 4 figs.,

table, 7 refs. DWB--The reflection and transmission coefficients of the abnormal E layer were measured by observation of

echoes. The abnormal E layer may be a horizontally stratified

layer of ionization with a total thickness of 5 km. The collision frequency in the height 110-135 km is found from 1.5 to

4. 104 sec -1. -A. A.

A-259 Briggs, B. H. and Phillips, G.J. (Cavendish Lab. Cambridge,

Eng. ), The determination of wind velocities in the ionosphere, U. S. Air Force. Cambridge Research Center, Geophysical

Research Papers, No. 11:199-203, 1952. fig. , 3 refs. Discussion. DWB—Drift velocities of 70 m/sec were measured. The

W-E component is westward at night, decreases during the day

and becomes eastward during the summer months, and is more

regular than the N-S component usually of much smaller magnitude. The observations were made during the past three

years at the Cavendish laboratory, Cambridge, Eng. The re- ceivers were placed 100-200 ms apart at three points of a rec- tangle. Wave length about 150 mr. --W. N.

A-260 Briggs, B.H. and Spencer, M. , Horizontal movements in the

ionosphere. Physical Society of London, Reports on Progress

in Physics, 17:245-280, 1954. 21 figs. , 4 tables, 40 refs.

DWB—In the E region closely spaced receivers and meteor observations give a mean velocity of 80 m/s and regular diurnal

variations represented by a vector of 30 m/s rotating clockwise (in N. Hemisphere) in 12 hours, directed N at 0300 and

1500. In summer a mean velocity of 50 m/s towards E is superposed. An upward increase of about 3. 6 m/s per km has

been observed. In the F region there is a component averaging 100 m/s towards E with diurnal variation and with changes

in periods of magnetic disturbance. There is a component

towards N in summer and S in winter (in N. Hemisphere). Results of non-radio methods are briefly summarized. --C.E. P.B.

A-261 Briggs, B.H. (Cavendish Lab. , Cambridge, England), Some

characteristics of sporadic -E ionization as determined by a rapid frequency sweep experiment. AGARDograph, Paris, No.

34:151-161, Sept. 1958. 8 figs. , 10 refs. , 3 eqs. DWB (629.

1323 N864a)--In the experiments described the frequency of a pulse transmitter was varied rapidly over a frequency range of

1/2 Mc/s in about 1/2 sec. , and a receiver was kept in tune

by electronic means. The amplitudes of echoes from the Eslayer and the F-layer were recorded as functions of frequency.

By comparison with the theory of reflection from a "thin" ionized
79

layer the thickness of the Es -layer is determined. Some re- cords also enable the collision frequency of electrons to be

found from a study of the absorption near the critical frequency of the Es -layer. Other results relating to the fading of

the Es and F echoes are described. --Author's abstract.

A-262 Brown, F. W. , Radio propagation research at the National

Bureau of Standards. American Journal of Physics, 26(9): 628-

634, Dec. 1958. table. DLC--The brief historical review is

followed by a review in summarized form on the regular ionospheric propagation, ionospheric scattering, sporadic E, meteor burst propagation, airglow, radio astronomy, other special investigations and the special efforts during IGY. Results of the studies are claimed to have saved millions of

dollars in military application. --W.N.

A-263 Brown, J.N., Automatic sweep frequency ionosphere recorder

model C-4. Institute of Radio Engineers, Proceedings, 47(2):

296-300, Feb. 1959. 3 figs. , 4 refs. DLC--Modus operandi,

along with illustration and block diagram are given. Primarily constructed for "virtual height" measurements, the automatic equipment has been used in oblique-incidence backscatter

as well as two-station synchronized pulse experiments. --W. N.

A-264 Brysk, H. , Measurement of the scattering matrix with an intervening ionosphere . Communications and Electronics, (39):

611-612, Nov. 1958. eqs. DLC--The brief theoretical discussion on backscattering shows that a complete S-matrix specification needs either (1) an adquate determination of the Faraday rotation or (2) the physical knowledge pertinent to the observation as gained from other sources. --W.N.

A-265 Budden, K. G. , I., The propagation of a radio-atmospheric.

Philosophical Magazine, Ser. 7, 42(324):1-19, Jan. 1951. 7

figs. , 15 refs. , 10 eqs. , 2 append. DLC--The propagation of

sferics depends on the nature of the boundaries of the waveguide. Since the ionosphere is an imperfect conductor, the

distance critical frequency and other properties of transmission will vary and the impulses will be distorted at great distances from the source. It is shown that the nature of the

source is not important. The model worked out in this paper

is idealized and shows the fractional reduction in intensity

at 1000 km. for various frequencies, and the wave form and

other features for long waves. --M. R.

A-266 Budden, K.G., The propagation of a radio atmospheric. Pt. 2 . Philosophical Magazine, London, 7th Ser. , 43(346): 1179-1200,

Nov. 1952. 6 figs. , 15 refs. DWB--
80

The present paper gives the full mathematical theory and

shows how the characteristics of the wave-guide modes may

be determined in the most general case, provided that the re- fleeting properties of the earth and the ionosphere are known

as functions of the angle of incidence which is, in general,

complex. It is found that the wave-guide modes are of two

types, which are described as "quasi-transverse magnetic"

and "quasi-transverse electric. " Allowance can be made for

the curvature of the earth. A particular case is then discussed, in which the surface of the earth is assumed to be perfectly conducting, and the ionosphere is assumed to be a homogeneous ionized medium, with the steady magnetic field

of the earth superimposed. The results of numerical calculations are given, for a few special cases, in the form of curves. These show (i) the attenuation in the various modes as a function of frequency, (ii) the polarization characteristics of the

wave in typical modes and (iii) the amplitudes of the wave

which are excited in typical modes by a vertical electric dipole source. --From author's abstract.

A-267 Budden, K. G. and Yates, G. G. , A search for radio echoes

of long delay. Journal of Atmospheric and Terrestrial Physics,

2(5):272-281, 1952. 23 refs. DWB--An unsuccessful search

was made for echoes delayed 3-15 sec. The cause of such

echoes is discussed and they are tentatively attributed to "the

propagation of guided waves over long curved paths formed by

belts of ions outside the earth but fixed relative to it. " --C . E. P. B.

A-268 Budden, K. G. , The theory of the limiting polarization of

radio waves reflected from the ionosphere. Royal Society of

London, Proceedings, 215(1121) :215-233, Nov. 25, 1952. 2

figs. , 10 refs. , 97 eqs. DLC-Based on FORSTERLING's coupled wave equation (vertical incidence), equations are obtained

by which a solution representing a single characteristic downcoming wave above the limiting region gives criteria for determination of the limiting polarization when the wave reaches

the ground. Discussion of the application of the theory to

frequencies higher than I Mc/s furnishes no new information

of significance about the ionosphere. --W. N.

A-269 Budden, K. G. , The numerical solution of differential equations governing reflexion of long radio waves fronrthe ionosphere. Royal Society of London, Proceedings, Ser. A, 227

(1171): 516-537, Feb. 8, 1955. 22 refs. , 85 eqs. DWB--Two

methods are described for obtaining numerical solutions of

the differential equations which govern the reflexion of long

and very long radio waves from the ionosphere at vertical or
81

oblique incidence. Both methods have been used with the

EDSAC, the automatic digital computer of the University

Mathematical Laboratory, Cambridge, but the paper is not

concerned with the details of the EDSAC programming, nor with the large series of results that have been obtained. In

the first method the first-order simultaneous equations, derived from Maxwell's equations and the constitutive relations

for the ionosphere, are integrated by a step-by-step process

proceeding downwards. The integrations are started from

properly chosen initial solutions. From the resulting field

variables at the bottom of the ionosphere a reflexion coefficient matrix R is derived, whose elements include the familiar reflexion coefficients. Two integrations are needed for

each derivation of the elements of R. For the second method,

it is shown that the formulae for R for a level below the ionosphere can be applied also within the ionized medium, and

define a more general matrix variable whose elements are the

dependent variables in a new set of differential equations.

These are integrated by a step-by-step process as in the first

method. The solution obtained below the ionosphere gives

the required set of reflexion coefficients without further calculation. Only one integration is required for each derivation. The equations are given in full for certain important

special cases. --Author's abstract.

A-270 Budden, K. G. and Clemmow, P.C., Coupled forms of the

differential equations governing radio propagation in the ionosphere. Pt. 2. Cambridge Philosophical Society, Proceedings,

53(3): 669-682, July 1957. 10 refs. . 97 eqs. Includes errata

for Pt. 1 DLC--The four firstorder "coupled" equations governing the propagation of electromagnetic waves in the ionosphere, previously obtained in

symbolic matrix form (CLEMMOW and HEADING (4)), are ex- pressed explicitly in terms of the ionospheric parameters. The

physical significance of the equations is illustrated by considering the energy flux in one characteristic wave when coupling and damping are neglected. Three special cases are then

discussed for which second-order coupled equations are also

given, namely, the cases of (a) vertical incidence with oblique magnetic field, (b) oblique incidence with vertical magnetic field, (c) norizontal magnetic field in the plane of incidence. For case (a) the second-order equations are those previously derived by FORSTERLING (5). The form of the coupled

equations is physically illuminating and, in principle, suitable

for solution by successive approximations. Extensive numerical work has indeed been carried out on the second-order coupled equations in case (a) (e. g. , GIBBONS and NERTNEY (6),

and it is probable that the first-order coupled equations would

prove more advantageous. The present authors, however,
82

feel that better methods are available for purely numerical

work (e. g. , BUDDEN (3)), and that the chief interest of the

coupled form is that it shows the scope and limitations of the

physical conception of characteristic waves. --Authors' abstract.

A-271 Budden, K.G. (High Altitude Obs. , Colo. Univ.), Method

of calculating wave-guide mode characteristics when the ionosphere is not sharply bounded. U. S. National Bureau of Standards, NBS Report, 5050, March 15, 1957. 9 p. 6 refs. , 22

eqs. DWB--When discussing the propagation of very low frequency radio waves to great distances, it is convenient to

treat the space between the earth and the ionosphere as a wave guide. A method is described for calculating the characteristics of the wave guide modes when the electron density

and collision frequency vary continuously with height in any

specified way. The method is given for the case when the

electric field of the wave is in the plane of incidence, but it could be applied also to horizontally polarized waves. The

earth's magnetic field is neglected, but a possible extension

of the method to include the effect of the earth's field is described. --Author's abstract.

A-272 Budden, K.G. (High Altitude Obs. , Colo. Univ.), Effect of

small irregularities on the constitutive relations for the ionosphere. U. S. National Bureau of Standards, NBS Report, 5081,

May I, 1957. 32 p. 3 figs., 5 refs. , numerous eqs. DWB--

Irregularities in the ionosphere which are small compared with

one wave length may modify the constitutive relations, and

hence, may affect the refractive indices for electromagnetic

waves. The modifications are in some ways similar to those

which would be introduced into the Appleton-Hartree formula

by a Lorentz force. The theory is given first for the case when

the irregularities extend only in one dimension, and it is found

that even in a loss -free medium the refractive index now has an

imaginary part which might be associated with loss of energy

from the wave by scattering. The theory for three dimensional

irregularities is then discussed, but is more difficult and a method of successive approximations is used. The results indicate that small irregularities may play an important part in

the propagation of very low frequency radio waves in the ionosphere. In particular, they may explain why "whistlers" are observed only on comparatively rare occasions. --Author's

abstract.

A-273 Bureau, Robert (Nat. Lab. of Radioelectricity, Bagneux, near

Paris), Reseau d'enregistreurs de P. I. D. B. (reinforcements

brusques) sur 11.000 metres. (Network of recorders of ionospheric perturbations with sudden commencements on 11, 000 m. )
83

International Council of Scientific Unions, Brussels, 8th Report of the Commission for the Study of Solar and Terrestrial

Relationships, Rome, Sept. 1952, p. 10-11, pub. 1953. 2 figs.

DWB--Running annual sums of monthly numbers of sudden ionospheric perturbations, 1929 through 1951, show a very close

parallelism with sunspot relative numbers. P. I. D.B. only

give intensifications between wave lengths of about 6000 and

17, 000 m. This is illustrated by records on 2 - 24 km at Bagneux and Poitiers, on June 17-18, 1941. --C. E. P. B.

A-274 Burkard, O. , Ionosphcirenbeobachtungen im Polargebiet . (Observations of the ionosphere in polar regions.) Archiv fur

Meteorologie, Geophysik und Bioklimatologie, Ser. A, 1(1):

93-99, 1948. 3 figs. , table, 4 refs. Summary in German,

English and French p. 93-94. DWB, MH-BH-Gives mean

hourly values of critical frequency of microwaves reflected

from F-layer for each month June 1944-April 1945 at Tromso,

N. Norway; maximum near noon and secondary maximum in

early morning. Critical frequency much lower on magnetically

disturbed than on quiet days. --C.E.P. B.

A-275 Burkard, O. , Studie zur weltweiten Ionospharenstoning vom

15. Marz 1948. (Study of the world-wide ionospheric disturbance on March 15, 1948. ) Archiv fur Meteorologie, Geophysik

und Bioklimatologie, Ser. A, 2(2-3): 314-324, 1950. 4 figs.

,

table, 8 refs. , eq. Summary in German, English and French

p. 315-316. DWB, MH-BH-Data from 30 magnetic stations in

all parts of the world are analyzed (for the strong disturbance

of March 15, 1948). Not all stations showed a decrease in

the critical frequency. Former theories are revised to show

dependence on magnetic field of earth and on local, not universal time.—M. R.

A-276 Burkard, Otto, Per Einfluss des maanetischen Erdfeldes auf

die F2-Schicht. (Influence of the geomagnetic field on the F2

layer. ) International Council of Scientific Unions. Mixed

Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 145-154. 3 figs. , 6 refs. English and

French summaries, p. 153-154. DWB—New discoveries regarding the local temporal variations of the F2 layer obtained from

recent ionospheric and magnetic records are: (a) the ionization in the forenoon is related to solar angle according to: 2

f - cos X +/3 (X = zenith angle of sun); (b) oc and 8 exhibit

geomagnetic influence; (c) yearly mean/? is directly proportional to product H cos <& where H is horizontal component;

(d) <x shows marked annual variation, with minimum in summer

(due to temperature effect); (e) in the morning the equatorial

zone (both magnetic and geographic) is strongly ionized in contrast to noon values. --Author's abstract.
84

A-27 7 Burkard, Otto, Isanomalen der F2-Ionisation. (Isanomals of

F2 ionization. ) Journal of Geophysical Research, 56(4):595-

600, Dec. 1951. 4 figs. , 3 refs. DWB--Author calculated

the departures of the maximum electronic concentration in the

F2 layer from the corresponding monthly mean value and presents maps with isanomals for northwest and Central Europe.

The surprising result is the appearance of intensive turbulence (Grossturbulenz) in the F2 layer. The problem is whether this turbulence phenomenon is connected with shifting

of masses or is limited by the electrical state. --A. A.

A-278 Burkard, Otto, Modell der Ionosphare . (Model of the ionosphere. ) Die Naturwissenschaften, Berlin, 45(21):507, Nov.

1, 1958. 1 fig. DLC --Russian commentary, makes mention

of an unexpected concentration of electrons at an altitude of

470 cm that was established by a rocket on the 21st of Feb.

1958; so remarkable indications concerning electron concentration in that part of ionosphere have been collected. The

author shows that according to these observations the model

of the ionosphere he published in Geofisica Pura e Applicata

(1957) is valid.

A-279 Burke, M.J. and Jenkinson, I. S. (both. Physics Dept. , Univ.

of Queensland, Brisbane), Ionosp heric drifts at Brisbane. Australian Journal of Physics, Melbourne, 10(3): 378-386,

Sept. 1957. 7 figs. , table, 9 eqs. DLC --Examination of fading of signals recorded at closely spaced receivers has been

used to measure the velocity of horizontal drifts of ionization

in the ionosphere. Systematic observations have been made

for a period of 2 yrs, on a frequency of 2. 28 Mc/s. The re- sults show good agreement with the horizontal velocities of

ionized irregularities in the E and F2 regions of the ionosphere as determined by other methods at similar latitudes. The

speeds are less than those observed at higher latitudes. The

results for the E region have been analyzed for 24, 12 and 8

hr solar harmonics. The 12 and 8 hr harmonics show large

seasonal phase changes in the northward component, in fair

agreement with the results at higher latitudes in summer only,

whereas the phase for the eastward component is generally

consistent with the results at higher latitudes for all seasons.

The F region 12 hr harmonic has a larger seasonal phase change

in the eastward component than in the northward component.

--Authors' abstract.

A-280 Cahill, Laurence J. , Jr. and Van Allen, James A. (both, Dept.

of Physics, State Univ. of Iowa), New rocket measurement of

ionospheric currents near the geomagnetic equator. Journal of

Geophysical Research, Wash., D.C. , 63(0:270-273, March

1958. 2 figs. DLC-
85

Gives record of new rocket measurement of ionospheric cur- rents as conducted by the State University of Iowa Rockoon

Flight No. 86 at 161° W long, and 00° lat. on Oct. 18, 1957.

The results of this investigation prove the existence of electrical currents in the lower ionosphere. The analyses of other

findings are given. Other magnetometer flights are being studied, and they may yield information concerning the latitudinal

extent of the equatorial current system. --N.N.

A-281 Cahill, Laurence J., Jr., Detection of an electrical current

in the ionosphere above Greenland . Journal of Geophysical

Research, 64(10): 1377-1380, Oct. 1959. 6 figs. , 4refs.DLC

--During a magnetic storm on Aug. 6, 1957, a rocket-borne

magnetometer was launched near the coast of Greenland. The

time and location of the flight and the magnetic measurements

obtained provide evidence that the rocket entered the postulated sheet current flowing across the polar cap. An estimate is made of the magnitude of the detected current. --Author's abstract.

A-282 Calcutta. Univ. Institute of Radio Physics and Electronics,

Research Report. Vol. 7, 1954/1955. Issued 1955? 142 p.

figs., refs. , eqs. DWB (M10. 535 C144r) -This is a series

devoted mainly to reprinting articles on ionospheric physics

by staff members of the Institute (founded in 1949). Even as

early as 1930, the director of the Institute, S.K.Mitra, made

ionospheric observations, at that time only experimental ionospheric station in the East. Vol. 7 of these reports contains

10 articles on such subjects as Ionization distribution in Fregion, Sporadic E ionization during thunderstorms and on

movement of Sporadic E clouds. --M. R.

A-283 Caldecott, R. and Robertson, W. J. , Techniques for the study

of radio wave propagation in connection with artificial satellites . Ohio. State University, Department of Electrical Engineering, Antenna Laboratory, Contract No. AF 33(616) -6137,

Project 889-3, Report, Feb. 28, 1959 (AD 213884).

A-284 Callet, R. M. and Helliwell, R. A. , Origin of "very low frequency emissions". U. S. National Bureau of Standards, Journal of Research, 63D(l):21-29, July-Aug. 1959. 4 figs. , 2

tables, 14 refs. , 9 eqs. DLC--Selective traveling-wave amplification in the outer ionosphere is postulated to explain very

low frequency emissions. Phenomena which can be explained

qualitatively by the theory are the hiss, quasi-constant tones,

dawn chorus, and related transients, and very long trains of

whistlers echoes. A quantitative example shows how the

theory can produce the general form of certain characteristic

discrete spectra "hooks" of emissions, and how this leads to
86

definite values of particle velocity and a law for the distribution of electron density in the outer ionosphere. --From authors' abstract.

A-285 Casselman, C. J. ; Heritage, D.P. and Tibbals, M.L. (all,

U. S. Navy Electronics Lab. , San Diego, Calif. ), VLF propagation measurements for the Radux-Omega navigation system. Institute of Radio Engineers, N. Y. , Proceedings, 47(5, Pt.l):

829-839, May 1959. 24 figs. , 7 refs. , eqs. DWB--This paper

describes special VLF propagation measurements in connection with a feasibility study of a long range navigation system.

Round-trip single -frequency measurement of phase stability

was made between Hawaii and San Diego on frequencies from

10.2 kc to 18. 2 kc in 1 kc increments. During Jan. 15 to 23,

1958, the standard deviation of phase stability on 12. 2 kc was

4/t sec daytime and 5jtt sec night time. One-way two frequency transmissions were monitered in San Diego and Washington,

D. C. , to determine the phase stability of a I kc difference

frequency for pairs of frequencies from 10. 2 kc to 18. 2 kc.

Data analyzed at time of submission of this paper (10. 2-16. 2

kc) indicate limitations of the two-frequency system for lane

identification (resolution of cyclic ambiguities corresponding

to one period of the carrier frequency). The techniques used

to instrument these tests are considered somewhat unique.

Data reported herein are general and applicable to any propagation study. The data being collected are leading to a better understanding of the mechanism of VLF propagation. -- Authors' abstract.

A-286 Caton, P. F. G. and Pierce, E. T. , The waveforms of atmospherics. Philosophical Magazine, London, Ser. 7, 43(339):

393-409, April 1952. 14 figs. , table, 14 refs. , 4 eqs. DWB

--A number of waveforms observed at Cambridge, Eng. , are

illustrated, and the technique of photography is described.

The forms are classified into 8 types, their occurrence described and origin discussed (initial leader, return strokes,

etc). The theory of multiple ionospheric reflections is considered; about 10% of the records give precise values of the

height (about 85 km) and distance of reflection. --C.E.P. B.

A-287 Chaffee, D.D., Jr. (Penna. State Univ. ), Statistical analysis

of "150-km" echo . Journal of Geophysical Research, 59(4) :549-

550, Dec. 1954. 2 figs. , 3 refs. MH-BH-An echo with a marked spring and fall maximum appears in the 150 kc/sec

band above the 130 km height and at an average of 150 km

(see Lindquist, J. of Atmos. & Terr. Physics, 4:10-27,1953)

was investigated. A strong 27-day periodicity appears on a frequency analysis graph, with probability of random cause

0. 05 when 3 years of data were used. It was found that for
37

long duration of the 150 km echo a high Kp (planetary magnetic

index) must exist. --M. R.

A-283 Chandra, Sushil; Gibbons, J.J. and Schmerling, E. R. , Verti - cal transport of electrons in the F region. Pennsylvania. State

Univ. Ionosphere Research Lab. , Contract AF 19(604) -3875,

Scientific Report No. 124, Oct. 1, 1959. 44 p. 24 figs. , 18

refs., 3 eqs. DWB (M10. 535 P415i) -The continuity equation

of electron density is solved to yield an expression for the

vertical transport which can be evaluated from electron-density-true-height profiles. A few numerical computations are presented of the vertical drift-velocities determined for the

four I. G. Y. stations — Huancayo, Talara, Panama and Washington. It is shown that the velocity is predominantly downwards during the night and upwards during the day at the equatorial stations. There is an apparent phase reversal from summer to winter at Washington. The order of magnitude of the

vertical velocity amplitude is 25 m/sec. There is substantial

agreement between the values calculated here from ionospheric data and those deduced from Sq

data on the dynamo theory.

--Authors' abstract.

A-289 Chao, S. H. , Wave theory of low frequency ionospheric propagation. Stanford University, Electronics Laboratories, Contract W23-099-ac-157, Final Report, 1952.

A-290 Chapman, J.H. , A study of winds in the ionosphere by radio

methods . Canadian Journal of Physics, 31( 4.): 120-131, Jan.

1953.--Winds in the ionosphere have been studied by a method

described by S.N. Mitra using the fading of radio echoes at

spaced receivers. A mean daily wind variation of nearly semidiurnal period and about 40 meters per second amplitude has

been observed at a nominal height of 110 km. (Region E). The

wind variation is consistent with the explanation that it is due

to tidal oscillations of the atmosphere. A wind variation consistent with that expected from lunar atmospheric tides has

also been detected at this level. The winds in the F region

appear to increase in velocity with an increase of magnetic

activity. A similar effect is not observed in the E region ex- cept during severe ionospheric disturbances.

A-291 Chapman, J. (Courtland's Ltd. , Coventry), The waveforms

of atmospheric and the propagation of very low frequency radio

waves . Journal of Atmospheric and Terrestrial Physics, London, 11(3/4) :223-236, 1957. 14 figs. (incl. photos), 25 refs. , eqs. DLC- -Experimental observations upon atmospherics by

several techniques are described. It is shown, in particular,

that the results obtained for wave forms and for frequency

spectra can be interrelated. The frequency spectrum of the
88

electromagnetic disturbance at the source— the lightning discharge — is considered, and evidence is presented indicating appreciable differences, in this respect, between individual flashes. The interpretation of the results, on the basis

of wave-guide theory, applied to the space between the earth

and the lower ionosphere, is considered; this approach is entirely successful qualitatively, but quantitatively the agreement is less satisfactory. --Author's abstract.

A-292 Chapman, J. and Pierce, E. T. (both. Cavendish Lab. , Cambridge, Eng. ), Les types d'ondes, les spectres de frequence

et la propagation des atmospheriques . (Wave types, frequency

spectra and propagation of atmospherics. ) L'Onde Electrique,

Paris, 37(362): 523-525, 1957. 4 figs. , 5 refs. DLC--From a

statistical analysis of the relation between wave forms and

frequencies of sferics recorded at Cambridge, Eng. , curves

of wave type frequency correlation are deduced. Results of

propagation measurement over 18 Mc are consistent with the

waveguide mode of propagation advanced by BUDDEN (1951).

-G.T.

A-293 Chapman, Sydney, Radio fade-outs and the associated magnetic variations. Journal of Geophysical Research, 42(4) :417-

419, 1937. --States that Birkeland had some insight into the

fade-out types of magnetic disturbance in his 1908 book. Discusses notation. --L. A. M.

A-294 Chapman, Sydney, Some causes of winds in the ionosphere.

I.U.G.G. Bulletin d'Information, 3(6):303-311, July 1954. DWB

--As the introductory paper of the Conference on Motions in

the Upper Atmosphere held at Albuquerque,

N.M. (Sept. 7-9, 1953), the CHAPMAN paper was the only

one given in extenso in this Bulletin. He discusses many

types of evidence of winds in ionosphere, dynamic influences

in lower and upper atmosphere, topography, oceanic heat

transfer and storage, latent heat, energy of dissociation, ionization and excitation, heat conduction, radiation absorption

and emission, friction and turbulence, external impact, electrostatic and electromagnetic influences, dynamo action in

ionosphere, turbulence in electromagnetic fields and dynamic

action by external forces and, finally, influence of lower atmosphere on ionosphere. Radio observations have played a major role in exploration of the ionosphere. --M. R.

A-295 Chapman, Sydney and Davies, K. , On the approximate day- time constancy of the absorption of radio waves in the lower

ionosphere . Journal of Atmospheric and Terrestrial Physics,

13(1-2) :86-89, Dec, 1958. fig., 7 refs.
89

A-296 Chappell, D.W. G. and Henderson, C.L., The determination

of the horizontal velocity of ionospheric movements from fading records from spaced receivers. Journal of Atmospheric

and Terrestrial Physics, London, 8(3):163-168, March 1956.

fig. , 3 refs. , 17 eqs. DWB--RATCLIFFE has shown that, for

the Mitra formula for the velocity of ionospheric movements

to be valid, a long sample of fading record is necessary. This

paper presents a method of deriving the velocity which is not

dependent on a long sample of record, and is valid for any

arbitrary distribution of orientation of "lines of maximum amplitude. " The derived formula is compared with Mitra's formula, and the time delays from a fading record are analyzed.

The method is not suitable for use with Philips records. -- Authors 1 abstract.

A-297 Chatterjee, B. , Nature and origin of sporadic E regions as observed at different hours (over Calcutta. ) Journal of Atmospheric and Terrestrial Physics, 3(5):229-238, June 1953. 5

figs. , 19 refs. MH-BH--Reflection coefficients of Es echoes

show two types of ionization; a cloud or blob type mainly in

early morning attributed to ionization by sporadic meteors,

and thin layer type mainly at sunrise in E layer, attributed

to photo-detachment of electrons from negative ions of and

02 by sun rays from below the horizon. In afternoon and evening Es ionization was mixed thin layer and ion clouds coming

from above. Associated with thunderstorms was the mixed

type or the "blanketing" type. --C.E. P. B.

A-298 Chatterjee, B. (Inst, of Radio Physics and Electronics, Univ.

of Calcutta, Calcutta), Some regularities of the ionospheric

F region. Journal of Geophysical Research, Washington, D.C.

58(3):353-362, Sept. 1953. 5 figs. , 12 refs. Also his: Regu- larities in the F-region of the ionosphere . Nature, London,

173(4397) :262-264, Feb. 6, 1954. 2 figs. , 3 refs. DWB-It

has been shown recently by RATCLIFFE that, although the behavior of the critical frequency (and hence the maximum ionization density) of the F2 region is very irregular, that of its

total ion content regularities observed by RATCLIFFE are confined only to a few stations and disappear when the Fl - F2

bifurcation is large. It is shown in the present paper that if,

instead of the total ion content of the F2 region, that of the

Fl cum F2 region (H-.) is considered as a whole, then the re- gularities become much more marked. Further, the regularities are found to persist for all the three stations considered — Slough (Northern Hemisphere), and Singapore (equatorial

region) — even when the bifurcation is large. Certain peaks,

however, are found to occur on the otherwise smooth variations of the monthly mean values of n-n. These are explained

as due to tidal effects. The paper also shows that the observed regularities of the composite F region are in conformity
90

with the recent hypothesis that Fl and F2 belong really to one

ionized region, being produced by a common ionizing radiation from the sun. --Author's abstract.

A-299 Chestnov, F. I. , Zagadka ionosfery. (Enigma of the ionosphere. ) Moscow, Gosud. Izdat. Tekhniko-Teoreticheskoi Literary, 1954. 54 p. 24 figs. Nauchno-populiarnaia Biblioteka,

No. 70. DLC--The detailed structure of the ionosphere is

described and shown in an original schematic diagram. Ionization, twilight, night sky light, aurora, diurnal effects, magnetic field, magnetic storms in ionosphere, solar effects, radio propagation (long and short wave), ionospheric soundings

by radio impulses, sunspot effects, forecasts of radio propagation, meteor traces, radio radiation from stars and rocket

exploration of ionosphere are treated in condensed popular

technical form. --M. R.

A-300 Chestnov, F. I. , Zagadka ionosfery. (The riddle of the ionosphere. ) Moscow, Gosud. Izdat. Tekhniko-Teoreticheskoi

Literary, 1956. 62 p. 25 figs. , refs. (Nauchno-Populiarnaia

Biblioteka, No. 70.) DLC (QC880. C45 1956)--A popular scientific pamphlet discussing (with schematic illustrations) the

basic features of the ionosphere - the causes of the ionization, the 4 layers (D, E, Fl and F2) of the ionosphere and

their structure; twilight phenomena, light of the night sky, the

aurora, ionospheric storms, sunspots, etc. ; radio propagation

by ionosphere, short wave and radio echo sounding, forecasting radio weather, eclipse effects, radio astronomy, rockets,

new methods of ionospheric research, the IGY. The last chapters contain some recent material not included in the 1954 edition. --M. R.

A-301 Chivers, H. J. A. and Wells, H. W. (both, Jodrell Bank Experimental Station, Manchester Univ. ), A new ionospheric

phenomenon. Nature, London, 183(4669): 1178, April 25, 1959.

fig. , 5 refs. DWB--In order to eliminate man-made noise and

interferences a special study of some unusual radiations began at Jodrell Bank in Oct. 1958. Five separate total-power

receivers slightly differing but near 80 Mc/s were used;three

receivers were at Jodrell Bank, the other two at separate sites

at 1 km distance. Some ten instances of isolated increase of

the noise level were recorded by some of the instruments while

others simultaneously recorded decrease during the period Jan.

3-10, 1959. Again, on March 25, 1959 at 1400 U. T. a very

striking isolated event occurred. Facsimile recordings are given. Preliminary investigations of these rare, apparent pre- cursors of stepped-up solar activity and subsequent magnetic

storms and auroras, show no unusual solar or terrestrial effect for relationships. --W. N.
91

A-302 Chu, T. S. , Ionospheric scatter propagation at large scat- ter angles. Ohio. State University, Department of Electrical

Engineering, Antenna Laboratory, July 1957. This is a M. S.

thesis.

// A-303 Chvojkova, E. (Astron. Inst. Ondrejov), Uber den Weltumlauf der Radiostrahlen (Refraktion der Kurzwellen in nichtparabolischer Schicht) . (Radio propagation around the globe:

short wave refraction in a nonparabolic layer. ) Bulletin of

the Astronomical Institutes of Czechoslovakia, Prague, 5(5, 6):

104-108, 110-111, 1954. 5 figs. , 4 refs. , 7 eqs. Russian summary p. 111. DLC --Investigators of properties of ionospheric

layers usually have a preference for assuming a parabolic layer. In this paper a new type of layer is introduced, very similar to the Chapman layer. This new model makes it possible

to analyze the properties of a spherical layer in whose lower

boundary the electron density reaches the zero value gradually rather than abruptly. It appears that not only in the middle

but also in the lower boundary region of a non-parabolic layer

there is a narrow range within which a horizontally propagating wave is forced into a circum-global course as far as the

structure of the layer remains unchanged. --Trans, of author's

abstract.

A-304 Chvojkova, E. (Astronomical Inst, of the Czechoslovak Academy of Sciences), The refraction of radio waves by a spherical ionized layer. Journal of Atmospheric and Terrestrial Physics, N. Y. , 16(1/2): 124-135, Oct. 1959. 8 figs. , 9 refs., 27

eqs. DWB, DLC--A general expression is derived for the re- fraction of radio waves passing completely through a spherical

ionized layer, using a simple ray treatment. A similar formula is derived for the ray-path length. It is shown that when

certain approximations appropriate to the terrestrial ionosphere are made, neglecting absorption and the effect of the earth's magnetic field, the expression for refraction reduces to a simple form which has previously been derived by the author

using a less general method. The perpetual propagation of

radio waves along two levels in the ionosphere, the condition

for which appears in the derivation of the general formula, is

briefly discussed. It is shown that with slight modifications

the refraction formula is also valid for reflection, and an ex- pression giving the distance of the point of reflection in the

ionosphere from the transmitter on the earth's surface is derived. --Author's abstract.

A-305 Chvojkova, E. and Woyk, E. (Astronomical Inst. , Czech. ), The antipodal reception of Sputnik HI. Institute of Radio Engineers, N.Y., Proceedings, 47(6):1144, June 1959. fig., 4

refs. DWB--
92

Antipodal reception of Sputnik signals at Stanford, Calif, on

20 Mc reported by O. K. Garriott and O. G. Villard between two

afternoon passes, arriving from the SE. Conditions under

which the signal propagates around the world in either of two

ionized layers (a) without reflection or escape, (b) with es- cape only, and (c) with return to earth, are discussed and illustrated and an explanation given of why the antipodal point

is the best for return to earth. At this point transmission can

occur with equal probability regardless of which great circle

path is followed. Preferred direction of arrival depends on

ionospheric conditions at points where ray first touches ionosphere and leaves it, respectively. Critical frequency of layer must increase from point where ray first enters ionosphere

in order to prevent escape at next upward penetration of ionosphere. In mid latitudes levels containing the same electron

density must be more curved than the earth. No arrival can

be expected from polar directions because of rare polar ionosphere which would allow escape before mid latitudes were

reached; or from the south, but SW in forenoon and SE in afternoon would be preferred. SW passage would be less frequent

than SE, since these SW rays would have to pass the region

where the critical frequency falls to its morning minimum. In

the sunset, (P.M. ) region turbulence might produce multipath

propagation, but this would not destroy antipodal reception.

Therefore, at Stanford frequent antipodal reception in summer

afternoons from SE would be expected. --M. R.

A-306 Clark, Clayton and Peterson, Allen M., Motion of sporadic - E patches determined from high-frequency backscatter records.

Nature, London, 178(4531) :486-487, Sept. 1, 1956. 2 figs.

10 refs. DWB--Reflection of backscatter from ground or sea by

sporadic-E patches has been measured at Stanford, Cal. Mean

duration of patches 3 hr, mean speed 300 km/hr with peak at

250 km/hr and a few values exceeding 550. The direction was

predominantly towards west. --C. E. P. B.

A-307 Clemmow, P.C. and Heading, J., Coupled forms of the differential equations governing radio propagation in the ionosphere. Cambridge Philosophical Society, Proceedings, 50(2) -.319-333,

April 1954. 15 refs., 73 eqs. DLC--The equations for oblique

propagation in a horizontally stratified ionosphere with an oblique magnetic field are put in a form suitable for solution by

successive approximations. In the general case this "coupled"

form consists of four first-order differential equations, each

associated with one characteristic wave. In the special cases

of (a) horizontal magnetic field, and (b) plane of incidence perpendicular to magnetic meridian, two second-order coupled equations of a particular type can be derived, each associated

with a pair of corresponding upgoing and downgoing characteristic waves. These latter equations include those given
93

previously by FOSTERLING (1942) for vertical incidence. Cases

in which there is no coupling are briefly considered from the

point of view of the first-order equations. The general formulation provides a basis for assessing the validity of the standard "ray" approximation, alternative to that developed by Booker (1936), and brings out the nature of its breakdown in coupling and reflection regions. --Authors' abstract.

A-308 Clemmow, P. C. and Johnson, M.A. (both, A. S. R.E. , Portsdown, Cosham, Hants. ), A contribution to the theory of the

motion of weak irregularities in the ionosphere. Journal of

Atmospheric and Terrestrial Physics, N. Y. , 16(l/2_:21-36,

Oct. 1959. 3 figs. , 3 tables, 3 refs. , 62 eqs. DWB, DLC--

The motion of weak irregularities in an otherwise homogeneous

slightly ionized gas under the influence of electrostatic and

magnetostatic fields is investigated. The governing equations

are set out and the dispersion equation for harmonic plane wave

solutions is obtained and solved. It is shown that, to a good

approximation for ionospheric applications, and with the neglect of diffusion, a plane wave travels with negligible attenuation with a velocity which is (a) proportional to the magnitude of the electrostatic field, (b) independent of the wavelength, (c) dependent on the direction of the wave-normal. As

a particular consequence, any weak two-dimensional irregularity which is parallel to the direction of the magnetostatic

field travels unchanged; so also does any one-dimensional ir- regularity, and in this case the analysis is unaffected by its

strength. The effects of diffusion are examined. --Authors'

abstract.

A-309 Cohen, D. S. , Hourly measurements of ionospheric character- istics. Macquarie Island, 1950. Australian National Antarctic Research Expedition, 1947-1949, Interim Reports, No. 2,

March 1952. 81 p. Mostly tables. DLC (QC973. C6) -Using

equipment of the CSIRO Radiophysics Lab. , routine h'F ionospheric soundings have been made at Macquarie Island 54°29'

3, 158°58'E; geomag. 61°S, 243°E) since June 13, 1950. In

this report, hourly values for June to Dec. 1950 are published

forf°F2 , f°Fi, f dE, FES , h'F2, hpFo, h'Fi, h'E, h'Es

, (M3000)

F2, (M3000)F{. --M.R.

A-310 Cole, A. W. , V. H. F. communication by ionospheric scatter.

Electronic Engineering, London, 28(340): 230-235, June 1956.

6 figs. , table, 12 refs. DLC--Scattering by random variations

in the E layer is effective below 30 Mc/s for distances up to

1400 mi, and is suitable for telegraphic traffic. The technical

problems of transmission and reception are discussed. -- C.E.P.B.
94

Cologne. Universitat. Meteorologisches Institut, Ergebnisse

A-311 der Ionospharenbeobachtungen. (Results of ionospheric observations. ) No. 1, 1957. Latest issue seen, No. 3, 1958.

18 p. Almost entirely tables. Preface, No. 1, signed H.

Berg. --Ionospheric disturbances have been investigated by

the impulse-echo method since 1941-42 at the Cologne University. As of 1954 the identical problem was studied simultaneously at the Cavendish Institute in Cambridge, and in 1956

the studies gained by reconstructional improvement of the instrumentation described. The observations are conducted at

00. 00 - 24. 00 3 days a month. The approximately 20 extremes obtained during the 5 min. runs are processed to yield: number

of echoes, time differences, amount of mean time vector direction of the mean ionospheric displacement vector, m/sec

velocity of the disturbances, apparent height of the reflective layer which are here tabulated accordingly. In issue No.

1, Nov. 7, 1956 - Feb. 18, 1957, in No. 2, March 25, 1957 - Aug. 26, 1957, and in No. 3, Sept. 21, 1957 - May 19, 1958.

-W.N.

A-312 Colwell, R.C. and Friend, A. W. , The D -region of the ionos- phere. Nature, London, 137(3471): 782, May 9, 1936. DLC--

Characteristics of the D -region were established by transmitting 60 pulses per sec, each pulse of 10 sec duration received visually reflected some 200 m from the transmitter. The

experiments were conducted during 1935 at West Virginia Univ.

Dept. of Physics. --W.N.

A-313 Commission Mixte de 1 'Ionosphere. Troisieme reunion. Canberra (du 24 au 26 aout 1952) . (Mixed Commission on the Ionosphere. Third meeting. Canberra (August 24-26, 1952). ) International Union of Geodesy and Geophysics, Bulletin d'lnformation, 2(2):377-380, April 1953. DWB--Discussion on Ionospheric storms, changes during solar eclipses, conductivity

of ionosphere, radio auroral echoes, and International Geophy

sical Year 1957-58. A comprehensive program is outlined for

the latter. --M. R.

A-314 Cones, H. N. ; Cottony, H. V. and Watts, J. M. , A 600 ohm

multiple-wire delta antenna for ionosphere studies. U. S. National Bureau of Standards, Journal of Research, 44(5): 475-488,

May 1950. 11 figs. DWB--This paper describes the design and

the performance of a multiple-wire delta antenna developed for

use with high output impedence, vertical-incidence ionosphere

sounding equipment. Graphs are presented showing the terminal impedence of this antenna over the separating frequency

range (1 to 25 Mc), using various lengths of open-wire transmission line. The results of pattern measurements using model techniques are given, showing the expected radiation
95

characteristics of the full-scale antenna. A practical test of

the comparative merits of the antenna is described in which

ionosphere records obtained by the use of this antenna are compared with those obtained by the use of a larger antenna

developed previously. --Authors' abstract.

A-315 Coroniti, S.C. and Penndorf, Research concerning ionospheric anomalous propagation in the Arctic. Avco Research and

Advanced Development Division, Scientific Report, Feb. 1958.

A-316 Cottony, H. V. , Radio noise of ionosphere origin. Science,

v. Ill, p. 41, 1950. --On Nov. 23, 1949, when cosmic noise

was recorded at very high levels, a solar radiometer was used

to determine whether the noise was coming from the sun or the

whole sky. The radiometer was adjusted to 50 Mc/s, No

change in intensity was observed when the Wurzburg Antenna

was pointed toward different parts of the sky. It is presumed

that this noise was of terrestrial origin, generated in the outer atmosphere of the earth.

A-317 Counter, V. A. , Propagation of radio waves through the tropo - sphere and ionosphere. Lockheed Missile Systems Division,

LMSD-2066-RI, May 14, 1958. (Corrected version of the LMSD206S).

A-318 Court, G. W.G. , Ionospheric wind determination from spaced

radio receiver fading records . Journal of Atmospheric and Terrestrial Physics, 7(6):333-340, Dec. 1955. 11 figs. , 4 refs.

DWB--A method of determining winds is described using a fixed aerial and one moving in a circular path around it. The

wind direction is given by the line of the aerials when optimum

correspondence of records is obtained, and the time delay indicates the velocity. --C. E. P. B.

A-319 Court, G.W. G. and Gilfillan, E.S. , A determination of ionospheric winds for a 24-hour period. Journal of Atmospheric and

Terrestrial Physics, London, 8(3):169-170, March 1956. 2 figs.,

2 refs. DWB--Records from 3 spaced aerials at Lower Hutt,

New Zealand, for 24 hours on Jan. 17, 1953 were analyzed. Elayer wind varied irregularly from S at Oh local time through W

and N to SE at 12-14h (Oh G. m. t. ) and back again. Mean velocity was about 80 m/s. --C. E. P. B.

A-320 Cowen, Robert C. and Landsberg, Helmut, Probing earth's

secrets. Christian Science Monitor, June 28, 30, July 5, 7,

12, 14 and 19, 1951. photos. Abstracted from reprint. DWB--

The work of the Geophysical Research Directorate of the Air

Force Cambridge Research Laboratories is brought to the general public in this series of 7 articles. In the introductory
98

article HELMUT E. LANDSBERG determines the field and ex- plains the importance of geophysics. The remaining 6 articles are by ROBERT C. COWEN of the Christian Science Monitor and bear the titles: 2. Air Center set for research in geophysics; 3. Air Force lifts lid on secrets of atmosphere; 4.

Probing sound waves aid in study of atmosphere; 5. Rocket '- labs' keep Air Force informed; 6. U. S. Air Force seeks to

end guesswork in forecasts; 7. Radio waves investigate ionosphere. A few photos, mostly showing equipment, are added.

--G.T.

A-321 Cracknell, R. G. , Trans equatorial propagation of VHF sig- nals. QST, 43(12):11-17, Dec. 1959. DLC -Using 50.4 Mc/s

transmission, several different propagation types are discussed in general, and in particular the so-called TE propagation. The transmissions were conducted from Salisbury,

S. Rhodesia since Sept. 1957. TE propagation is one type

between two points of opposite sides of, and at least 1000

miles from the geomagnetic equator .- -W. N.

A-322 Crary, J. H. ; HelliwelJ, R.A. (both, Stanford Univ. ), and

Chase, R. F. (Boeing Airplane Co. , Seattle, Wash. ), Stanford-Seattle whistler observations. Journal of Geophysical

Research, Wash., D.C., 61(l):35-44, March 1956. 6 figs.

,

4 refs. , 4 eqs. DLC --Simultaneous observations of times of

occurrence of whistlers were made at Seattle, Wash. , and

Stanford, Calif. , two hours every week from Oct. 1951 to Oct.

1952. Times were measured to an accuracy of about + 1 sec. The objective was to determine the percentage of whistlers

received at either station which were coincident at both. A

total of 318 whistlers was received at Stanford and 283 at

Seattle during simultaneous observations. The occurrence

rate of whistlers (during a two-hour period) varied from to

roughly 55 per hour at Stanford and from to 70 per hour at

Seattle. The correlation between the occurrence rates was

poor. The number of true coincidences was found by subtracting the number of chance coincidences from the number

of total coincidences. A method for computing the number of

chance coincidences from a knowledge of the time intervals

between whistlers at the one station was derived. The analysis showed that approximately 22 percent were observed simultaneously at both stations. This result is examined in relation to possible theories of whistler origin and propagation,

and is shown to support the Storey-Eckersley theory. --Authors'

abstract.
97

A-323 Crichlow, William Q. (Natl. Bureau of Standards, Boulder,

Colo. ), Noise investigation at VLF by the National Bureau

of Standards. Institute of Radio Engineers, N. Y. , Proceedings, 45(6): 778-782, June 1957. 9 figs. , 7 foot-refs. DLC--

The principal objective of the Radio Noise Section at the National Bureau of Standards is the establishment of a regular

service for predicting the levels and characteristics of radio

noise. The various steps necessary to establish such a ser- vice at NBS are summarized. The characteristics of atmospheric noise vary with location, frequency, and time, and

methods of dealing with these variations are discussed. Also

discussed are new predictions of world-wide noise levels

which have been prepared for the International Radio Consultative Committee (CCIR). --Author's abstract.

A-324 Crichlow, W. Q. ; Disney, R. T. and Samson, C.A. , Atmospheric radio noise summary for the period June 1 through Nov.

30, 1957. U. S. National Bireau of Standards, NBS Report

5556, Feb. 20, 1958. 25 p. 8 figs., 16 tables. DWB (621.

384 U58at). Also their Atmospheric radio noise for the period

Dec. 1. 1957 through Feb. 28. 1958. Ibid. , 5580, June 23,

1958. 3 p. 7 figs., ref. DWB (M94. 6 C928at)--The first

article is a summary report of noise measurements made during the period June 1 through Nov. 30, 1957 by stations in the

recording network which is supervised by the National Bureau

of Standards. Stations engaged whole time or part of the period were as follows: Boulder, Colo. ; Bill, Wyo. ; Front Royal,

Va. ; Marie Byrd Base, Antarctica; Balboa, Canal Zone; Ibadan, Nigeria; Thule, Greenland. Studies in this field are intended to produce more specific recommendations for future

noise predictions. In the second article, radio noise measurements during the period Dec. 1, 1957 through Feb. 28, 1958

have been summarized for the following stations: Boulder, Cob;

Bill, Wyo. ; Front Royal, Va. , and Balboa, Panama Canal Zone.

Details of data analysis show the existence of contamination

from signals, man-made noise, and receiver noise. A procedure adopted to eliminate these effects and to obtain a "best

estimate" of a true atmospheric noise level at each station is

described. Differences between the predictions and observations are discussed by time blocks. --N.N.

A-325 Crombie, D.D. (Phys. Lab. D. S. I. R. Lower Hutt, New Zealand), Differences between the east-west and west-east pro- pagation of VLF signals over long distances . Journal of Atmospheric and Terrestrial Physics, London, 12(2/3): 110-117, 1958.

3 figs. , 3 tables, 10 refs. , 2 eqs. DLC--An early suggestion

by ROUND, ECKERSLEY, TREMELLEN and LUNNON that VLF

signals received from the west are less attenuated than those

from the east is investigated. The original evidence, together
98

with further experimental data, give strong support to the

hypothesis. The outline of a possible explanation of the

effect is given, --Author's abstract.

A-326 Crombie, D.D.; Allan, A. H. and Miss Newman, M. , Phase

variations of 16 Kc/s transmissions from Rugby as received in

New Zealand. Institution of Electrical Engineers, Proceedings,

B, 105(21): 301 -304, May 1958. 4 figs., 9refs., eqs. DLC--

The results of approximately one year's measurements of the

diurnal phase variation, in New Zealand, of the highly stable

16 Kc/s transmission from GBR are given and discussed. It can be considered that the signal is received by the short

great-circle path, the observed phase variations appear to be

in accordance with propagation via the TMqi mode which exists between parallel plane metallic sheets. --Author's abstract.

A-327 Crompton, R. W. , Huxley, L.G.H. and Sutton, D.J. , Experi- mental studies of the motions of slow electrons in air with application to the ionosphere . Royal Society of London, Proceedings, Ser. A, 218(1135): 507-519, July 23, 1953. 7 figs., 3

tables, 14 refs. , 30 eqs. Also: Huxley, L.G.H. , Alternative

developments of the theory of radio wave interaction. Ibid. , p. 520-536. 3 figs., 2 tables, 13 refs., 56 eqs. DLC--Empirical formulas are found for drift velocity, collision frequency,

electronic temperature and mean energy loss per collision.

Collision frequency can be related to pressure (p mb) by v

= 7.02 x 10^p. The average energy lost in a collision is computed and applied to radio wave interaction. It is found that

the theory of this interaction requires revision, and an alternative theory is given in the second paper. --C. E. P. B.

A-328 Croom, Sheila, Robbins, Audrey; Thomas, J. O. , Two anom- alies in the behavior of the F2 layer of the ionosphere. Nature

184 No. 4704, 2003 (Dec. 26, 1959). 3 figs. , table, 6 refs.

DLC--This brief discussion treats (1) the geomagnetic anomaly

and (2) an unexpected diurnal asymmetry. N(h) profiles for

some selected stations were computed and tabulated and curv- es featuring magnetic dip. Pre-noon electron densities were

found to be^ the corresponding afternoon ones, at fixed F - regions in Sept. 1957. Further investigation may establish

the extent of the diurnal asymmetry. --W. N.

A-329 Crow, D. A. ; Kitchen, F. A. ; Isted, G. A. and Millington, G.,

A disturbing factor in very high frequency communications via

ionospheric forward scatter. Nature, London, 178(4545): 1280-

1283, Dec. 8, 1956. 10 figs. , 5 refs. DLC--
99

Investigations into the cause of the radio interference disastrous to teleprint communication on 37. 30 Mc/s between Gibraltar and the United Kingdom in 1955 are reported on. Indirect pulse modulation of the transmissions identified the components of the multi-hop delayed signals discussed. A safe

10 db signal/interference ratio requires a 30 db improvement

of the present array. --W. N.

A-330 Crow, Edwin L. and Zacharisen, Donald H. , Pilot study of

the preparation of world maps of F2 critical frequencies and

maximum usable frequency factors. U. S. National Bureau of

Standards, NBS Report 5560, Feb. 28, 1958. 68 p. 15 figs.

,

13 tables, 3 refs. , 15 eqs. DWB (621.384 U585pil)--The Central Radio Propagation Laboratory is undertaking the preparation of G. M. I. contour maps, possibly semipermanent, for

predicting F2 layer maximum usable frequencies. Maps are

to be given for each month of the year and each even hour of

G.M.T. A degree of semipermanency is hoped for by presenting maps of foF2 and the 4000 km muf factor for 12-month run- ning average Zurich sunspot number of 50, and also of the

rates of change of these parameters with sunspot number. Thus

radio propagation conditions can be predicted directly from

these maps once the average sunspot number is predicted. The

pilot study reported herein examined the available data from

about ten ionospheric sounding stations in detail and drew 74

contour maps from data of all stations in order to evaluate the

precision attainable with such maps and to choose between alternative methods of preparation. The total standard deviation of the error in predicting muf with these maps was found

to be about 0. 9 Mc at zero distance and about 3. 1 Mc at 4000

km, increasing slightly with sunspot number. A comparison

of these maps, CRPL Series D, and Radio Research Station,

Slough, maps with foF2 observations recorded in the F series

gave total standard deviations of predictions of, very roughly,

1. 1, 1. 1 and 1. 6 Mc respectively. --Authors' abstract.

A-331 Cummack, C.H.; King, G. , Disturbance in the ionospheric

F region following the Johnston Is nuclear explosion. New

Zealand, Journal of Geology and Geophysics, 2(3):634, 1959.

A-332 Cummack, C.H. (Christchurch Geophys. Observ. , New Zealand), "Chapman behaviour' in the lower ionosphere . Journal

of Atmospheric and Terrestrial Physics, New York, 14(3/4):

229-235, June 1959. 4 figs. , 6 refs. , 9 eqs. DWB, DLC--

It is shown that Chapman's relations for the variation of critical frequency and height of a layer with solar zenith angle

can be applied to any point on that layer and that it is not

necessary to assume monochromatic radiation. These results

are then applied to electron density vs. height profiles and it
100

is shown that "Chapman behaviour" can be detected to a height of 160 km being consistent with a scale height of 10 or

15 km. --Author's abstract.

A-333 Cutolo, M. ; Carlevaro, M. and Ghergi, M. f Esperionze gull * interazione con risonanza fra radioonde nella ionosfera. (Ob*-

servations on the interaction of waves in the ionosphere in re- lation to the gyrofrequency. ) Alta Frequenza, 15(2):111-117,

June 1946. fig. , table. DLC.

A-334 Cutolo, M. , Determinazione sperimentale delle curve di

risonanza nel moto deqli elettroni lenti dell' alta atmosfera.

(The experimental determination of the resonance curve in the

motion of slow electrons in the upper atmosphere. ) II Nuovo

Cimento, Ser. 9, 9(5):391-406, May l f 1952. 6 figs. , 2 tables, 9 refs. English summary p. 406. DWB—Review of "cross

modulation" in the ionosphere between two electric waves of

very different frequencies. The cross modulation is especially well expressed if the frequency of the modulated wave is

about equal to the local gyrofrequency — a resonance effect

called "gyro interaction. " Italian observations show an appreciable influence of the sunspots on this phenomenon. --

A-335 Cutolo, M. , Su di un nuovo fenomeno di interazione fra onde

ed elettroni liberi sottoposti al campjo magnetico terrestre.

(On a new phenomenon of interaction between waves and electrons subjected to the field of terrestrial magnetism. ) II Nuovo Cimento, Ser. 9, 9(8):687-698, Aug. 1952. 3 figs., 2

tables. English summary p. 698. DLC—The curious phenomenon of a wave with frequency near the gyrofrequency that interacts on itself is discussed and nomenclature suggested.

Graphical presentation on how the modulation percent of the

received radiation decreased to less than 40% of the originally

transmitted 80% is given. Technical difficulties retarded exact measurements of the frequency at which the minimum was

obtained hence the determination as to whether or not the values were higher or lower than the calculated gyrofrequency, because of ionospheric conditions, remains unsolved. -- W.N.

A-336 Cutolo, M., Measurements of the terrestrial magnetic field

in the E-laver. Nature, London, 172(4382): 774-775, Oct. 24,

1953. fig. , table, 2 refs. DWB—Describes briefly a method

of determining total intensity of earth's magnetic field by

self-demodulation of radio waves. Values found in Italy in

1949-1951 are around 0. 43 oersted. --C. E. P. B.
101

A-337 Dalgarno, A. (GRD, ARDC, Bedford, Mass. ), Ambipolar

diffusion in the F2-layer . Journal of Atmospheric and Terrestrial Physics, London, 12(2/3) :219-220, 1958. table, 18 refs. , 3 eqs. DLC--The densities of the diffused free-charges in the

F2-layer are considered too small by a factor of at least 4 or 5 and unacceptably rapid at the neutral particle concentration

as indicated by rocket measurements. Several scientists and

their research on the mobilities of ions in their gaseous states

are referred to. The commonly accepted diffusion coefficient

D, for an ion of mass Mj in a gas composed of particles of

mass M2 , is expressed thus:

where K is Boltzmann's constant; T, the absolute temperature;

A , the reduced mass mi m2/(M, + M2

); N2

> tne ^as number

density; and P, the average effective diffusion cross-section.

This is an important parameter in the discussions. --N.N.

A-338 Daniels, Fred B. and Bauer, Siegfried J. (both, U.S. Army

Signal Engineering Laboratories, Fort Monmouth, N.J. ), Mea- surement of the ionospheric Faraday effect by radio waves re - flected from the moon. Nature, London, 181(4620): 1392-1393,

May 17, 1958. 2 figs., 2 eqs. DWB--Using the rotation of

the plane of polarization of radio echoes from the moon it is

possible to determine the change in total electron content of

the ionosphere. This is a report on such an experiment made

the night of Jan. 8-9, 1958. Results indicated a change about

2. 2 times that computed for a parabolic layer using vertical

sounding data recorded at the transmitting site. --Based on Physics Abstracts, No. 5543, 1958.

A-339 Daniels, Fred B. and Bauer, Siegfried J. (both, U.S. Army

Signal Research and Development Lab. , Fort Monmouth, N. J. ) f Faraday fading of earth satellite signals . Nature, London,

132(4635): 599, Aug. 30, 1958. 2 refs. , eq. DWB--Very brief

note on British attempts to estimate ionospheric integral electron content up to the satellite's height by means of rate of

fading due to the Faraday effect. Too high values were obtained which may be explained by the omission of the satellite's radial velocity component in the theoretical expressions.

--W.N.

A-340 Daniels, F. B. and Bauer, S. J., The ionospheric Faraday ef - fect and its applications . Franklin Institute, Journal, 267(3):

187-200, March 1959. 7 figs. , 8 refs.
102

A-341 Datta, S. and Datta, R.N., Gyro-frequency in the Ionospheric regions. Indian Journal of Physics, 33(7): 316-324, 1959.

5 figs. , 3 tables, 11 refs. , 9 eqs. DLC—Gyro-frequencies in

E, Fl and F2 regions over Haringhata, were calculated from

measurements of ordinary (f Q

) and extraordinary (f x) critical

frequencies. Findings include the following: 1) magnetic

fields were higher than those expected from extra polation of

the magnetic field at ground level to the heights of the regions

by inverse cube law. 2) The marked semi-diurnal variation of

the gyro-frequency of the E region reaches minimum at midday.

3) No such variation found in Fl nor F2, average winter value

of the latter exceeds the summer value by 9%. 4) f x

- fQ

depends on high frequency values being lower than those at lower levels, as may be expected in quasi -transverse propagation.

--From authors' abstract.

A-342 Davids, Norman, Theoretical group heights of reflection of

150 kc/s radio waves vertically incident on the ionosphere.

Journal of Atmospheric and Terrestrial Physics, 2(6):324-336,

1952. 6 figs. , 4 tables, 6 refs. , 28 eqs. DWB--"It is found

that the rapid changes in polarization near the lower edge of

the E-region, called the 'coupling region, ' are very effective

in generating reflected waves or pulses under suitable conditions. ... At a higher level in the layer rapid variations in the

index of refraction for one of the characteristic wave components occur in what is called the 'reflection region'." The theory agrees with experimental results. —Author's abstract.

A-343 Davids, Norman (Penna. St. Coll., Ionosphere Res. Lab.),

Dispersion effects at 150 Kc/s a particular E-layer model.

Pennsylvania. State College. Ionosphere Research Laboratory,

Contract AF 19(122) -44, Ionospheric Research, Scientific Report, No. 31, Jan. 30, 1952. 62 p. 9 figs. , 3 tables, 9 refs.,

48 eqs. Appendix A, p. 35-62, Schrag, R.L., Magneto-ionic

calculations for a nighttime E-layer model at 140, 150, and 160

Kc/s. DWB.

A-344 Davids, Norman (Ionos. Res. Lab., Penna. St. Coll., State

College, Pa. ), Optic axes and critical coupling in the ionos - phere. Journal of Geophysical Research, Washington, D.C.,

58(3) :311 -321, Sept. 1953. 3 figs. , 9 refs. , eqs. Also in:

Pennsylvania. State College. Ionosphere Research Laboratory,

Scientific Report, No. 43, Jan. 30, 1953. 20 p. 3 figs. , 8

refs. , eqs. DWB--Critical coupling arises when, for a certain

critical N = N c and v = vc *ne coupling factor, which measures the degree of interaction between the ordinary and extraordinary modes, becomes infinite. Instead of attempting to solve

the standard coupled wave equations at or near this singularity, a different reference system is introduced based on the
103

principal directions of the three-dimensional dielectric ellipsoid. These directions depend only on the direction of the

earth's field, and are thus essentially constant over the ionosphere. Analogy with crystals, as pointed out by LANGEHESSE, suggests the possibility of optic axes in the ionosphere. It is shown here that such axes can exist in the presence

of collisions and that this is precisely the condition for critical coupling. The ionosphere acts isotropically at such a level, with no principal modes being singled out. Some application to data at 150 kc/sec is made. --Author's abstract.

A-345 Davids, Norman and Parkinson, R. W. , A long-wave solution

near critical coupling;. Pennsylvania. State Univ. Ionosphere

Research Laboratory, Contract AF 19(122) -44, Scientific Report, No. 54, Nov. 25, 1953. 8 figs. , tables, 17 refs. , eqs.

DWB--By using the reference system based on the principal

directions of the three-dimensional dielectric ellipsoid, it is

possible to put the coupled wave-propagation equations into a form where the coefficients are well behaved. This is particularly desirable for ionospheric models containing regions

near critical coupling. It is shown how the more usual equations can be transformed. "First order" results are obtained

for data at 150 kc/s, including scattering coefficients. It is

also shown that reflections exist at critical coupling, but that

their magnitudes are less than 10%. Methods of solution for

the exact equations are described. --Authors' abstract.

A-346 Davidson, David, Characteristics of sporadic-E ionization at

middle latitude . Harvard Univ. Cruft Lab. , Technical Report

No. 230, June 15, 1955. 85 p. tables, 41 refs. , eqs. numerous figs. (incl. photos). DWB--A major report on results of

1951-1954 studies of sporadic E phenomena using a 3-station

(Concord, Gloucester and Sandwich, Mass. ) base line of 100

km. Cloud velocities of 400 to 1000 km/hr, prevailing from

the ENE, around midnight local time, and favoring periods of

marked geomagnetic or auroral activity, were noted. Several

forms were observed, but the predominant form was that of multiple reflections from a thin layer at 100-120 km height. In Oct.

through Dec. there was an inverse relation between sunspot

and sporadic E incidence and even better if the square of the

foF2 non median values is used instead of sunspot number.

This relation breaks down at the equinoxes. Data, charts,

graphs and references are given in extenso. --M. R.

A-347 Davies, Frank T. (Telecommunications Estab. , Defence Res.

Bd. of Canada), The ionosphere over northern Canada . Arctic,

Montreal, 7(3/4): 188-190, 1954. DLC -Ionospheric research

carried out in Canada by the Telecommunication Div. of the

Dept. of Transport in cooperation with the Radio Physics Lab.
104

of the Defence Research Board is reviewed. The extent of

ionospheric stations established, the results of studies on

prediction of average height and electrical density of the ionosphere for given times of day and season, the radio noise

level of northern Canada and contemplated ionospheric re- search are discussed. --I. L. D.

A-348 Davies, Kenneth and Hagg, E.L., Ionospheric absorption

measurements at Prince Rupert. Journal of Atmospheric and

Terrestrial Physics, 6(l):18-32, Jan. 1955. 10 figs. , table,

12 refs. , 7 eqs. DWB-Observations in 1949-50 on 20 Mc in

54. 3vl, 130. 3 W, near the auroral zone are discussed. Noon

values of absorption show little dependence on solar zenity

angle X but are abnormally high in winter. Diurnal variation

of -log P is represented roughly by £ (cos % ) a where /&

varies from 9 to 35 and n, from 0. 82 to 0. 29 in individual months; mean values 20 and 0.5. Value of -log/5 increases linearly with 3-hour magnetic index K when K is above 4; mean

correlation 0. 59. There is a less close relation (0. 3l)with

sporadic E ionization. After discussion of these results it is

concluded that near the auroral zone ionization by UV radiation is modified by the influence of charged corpuscles. -- C E. P. B.

A-349 Davies, Kenneth, Some studies of the transmission of high

frequency radio waves via the ionosphere at oblique incidence. Brown Univ. Div. of Engineering, Providence, Rhode Island,

Contract AF 19(604)-2066, Scientific Report AF 2066/2, June

1958. 34 p. 17 figs., table, 14 refs., 42 eqs. -The anomalous reflection of high frequency radio waves from the ionosphere at frequencies near the maximum observed frequency is

described with graphical illustrations. The elementary theory

of its transmission via the ionosphere at oblique incidence

and the analytical results of the investigation are discussed.

This report also covers a description of the sweep frequency

pulse measurements conducted in the United States and in

Canada during 1952 through 1954. The data on how the anomalons propagation depends on the angle of incidence is obtainable from Canada where paths varying in length from about

1000 km to 6000 km are operated simultaneously. --N.N.

A-350 Davis, R.M., Jr. and Finney, J. W. (Central Radio Propagation Lab. , NBS, Boulder, Colo.), Interference effects of F2

propagation at VHF. U. S. National Bureau of Standards, NBS

Report, 6004, Oct. 15, 1958. 18 p. 14 figs. , 5 tables, 5 refs.

DWB (621.384 U585in)--F2 layer propagation is a major source

of longrange interference connected with operation of ionospheric -scatter communications circuits. The magnitude and var- iations of the interference are investigated in this report by
105

means of a study of the maximum usable frequencies for 4000

km transmission (F2 4000 MUF). The variable selected for

study is the frequency exceeded by the MUF for a given percentage of the total time over all the hours of the day. Values

of this variable have been derived for each 10 of latitude in

the E, I, and W zones, at three seasons of the year (December

solstice, June solstice, and equinox) and for low and high sunspot numbers. The basic data used for the computation of F2

4000 MUF were the charts of this parameter predicted in the

CRPL D -Series for 12-month periods representing low and high

sunspot numbers. The data were reduced to the desired values of F2 4000 MUF exceeded 1% and 10% of the total time by

a machine computation method. This consisted of the selection and testing of successive trial frequencies until values

were found that corresponded to the 1. 0% and 10. 0% MUF's to

the nearest tenth of a percent. The statistical considerations

underlying the use of this method are discussed in some detail. An outline is given of the exploratory steps that led to

the procedure finally adopted. Substantial revisions were made

in the values of F2 4000 MUF originally derived, on the basis

of observations of this quantity at several positions on the

earth's surface. The final data were incorporated in world charts applying to a given level (1% or 10%), a given season, and

either low or high sunspot number. A procedure is described

for using the charts to find the frequency required to limit scatter circuit interference to a specified level. Mention is made

of the uncertainties and limitations inherent in any effort to

predict the interference effects of F2 layer interference. The

twelve world charts of F2 4000 MUF can be used to estimate

both the mutual interference and the self-interference likely to

affect a given scatter-communications circuit. --Authors' abstract.

A-351 Davis, R.M., Jr. ; Smith, E. K. et al. (all, Natl. Bureau of

Standards, Boulder, Colo. ), Sporadic E at VHF in the U. S. A.

Institute of Radio Engineers, N. Y. , Proceedings, 47(5, Pt. 1):

762-769, May 1959. 11 figs., 2 tables, 15 refs. DWB--An an- alysis is made of sporadic E propagation observed on the Cedar Rapids to Sterling path during the four years, 1952-1955.

VHF transmissions over this path at frequencies of 27. 775 mc

and 49. 8 mc provided the Es data. At this latitude, the summer months receive the preponderance of sporadic E. Diurnally, sporadic E occurrence tends to favor the daytime and evening hours with peaks of incidence about 1000 and 1800. No

variation with sunspot number has been discerned. As a rule,

higher Es signal intensities are recorded at 28 than at 50 mc.

Cumulative distributions of signal intensity are presented for

the two frequencies. A relationship is found between the frequency dependence of Es signal intensities^ -70 db, relative
106

to inverse distance, and the distribution of fEs values at

Washington, D.C. The relationship promises to be useful in

the prediction of Es signal intensities on a world-wide basis.

An inverse correspondence is shown between sporadic E oc- currence and geomagnetic activity. The correspondence holds

only over selected time intervals. The frequency dependence

of received power under sporadic E conditions is different from

that during normal scatter. The median frequency exponent is

two or more times as large for sporadic E, and the exponents

cover a much wider range of values. This is tentatively ex- plained by considering the Es region to be composed of patches of intense nonuniform ionization, an hypothesis previously

used to explain vertical incidence data. --Authors' summary.

A-352 de Bettencourt, J. E. and Klemperer, H. , The beacon technique as applied to oblique incidence ionosphere propagation.

Institute of Radio Engineers, Proceedings, 38(7): 791-792, July

1950. 3 figs. , refs. , eqs. DLC- -Determining the transmission time of a. given mode via the ionosphere a technique similar to that used in microwave beaconry is described. An interrogator-responsor and a beacon transpondor was used over

the 2615 km path. »W. N.

A-353 Dedrick, K. O. ; Lynch, W. M. and Blanchard, H. P. , A brief

survey of ISO kc/s propagation. Stanford University, Electronics Laboratories, Contract W28-099-ac-157, Technical Report,

July 1950.

A-354 Delobeau, F. , La haute atmosphere: etat actuel des recher- ches sur les vents ionospheriques. (The upper atmosphere:

the current state of research on ionospheric winds. ) La Meteorologie, Paris, Ser. 4, No. 47:379-392, July/Sept. 1957.

13 figs. , 16 refs. , 15 eqs. French, English and Spanish summaries p. 379. DWB--The existence of local irregularities in

the distribution of ionization in the upper atmosphere gives

rise to ionospheric winds. The author then reviews the structure of the ionosphere including Chapman's hypothesis on the

production of electrons as a function of height, the equations

for the movement of electrons in the ionization layer, etc.

The procedure, theory and equations underlying the various

methods for measuring the speed of ionospheric winds are presented in detail; these methods are the method of MITRA which

observes at three neighboring points the fluctuation of an ionospheric echo from a vertically directed radio-electric emission,

the observation of meteor trails by radioelectric methods and

MUNRO's method which involved the recording of the heights

of reflection of a wave of fixed frequency in the F layer and in

three very distant points. The method of three receivers has

revealed the existence of variable winds in the E layer with a
107

mean velocity of 80 met/sec (extremes of 20 and 300 m/sec);

also the winds manifest a regular semidiurnal rotation. Comparable results have been obtained with the meteor method.

In the F layer the regular semidiurnal rotation is not observed,

instead there is a 24-hour period. The amplitude of the velocities is of the order of 100 m/sec. --I. L. D.

A-355 Delloue, Jean, Sur la direction d'arrivee et la polarisation

des atmospheriques siffleurs . (Direction of incidence and the

polarization of whistling atmospherics. ) Academie des Science, Paris, Comptes Rendus, 244(6): 797-799, Feb. 4, 1957.

DLC--An apparatus used for selective observation of whistling atmospherics is described. Observations made with the

apparatus show that whistling atmospherics always come from

a direction close to that of the geomagnetic field. The direction of an individual whistler varies simultaneously with its

polarization. The existence in the high atmosphere of very

small ionized regions of short duration was ascertained. -- Trans, of author's abstract.

A-356 de Maximy, Georges, L 'ionosphere et la prevision des frequ- ences en telecommunications (propagation des ondes decametriques) . (The ionosphere and the forecasting of frequencies in

telecommunications: propagation of decametric waves. ) Paris,

Editions Chiron, 1953. 54 p. 23 figs. (Les Cahiers de l'Operateur Radio). DLC (QC973. M3)--A practical manual with tables, nomograms, graphs, forms and examples, covering in several chapters the basic information on radio propagation, the

ionosphere (structure, sounding, variations, storms), refraction and absorption in D layer, forecasting frequencies, solar

relations, curves for prediction of propagation of decameter

waves and tables for determining the most useful frequencies.

-M. R.

A-357 Demers, Pierre, Theory of diffusion in the course of develop- ment of the lower ionospheric clouds . Canadian Journal of

Physics, 36(6):704, June 1958.

A-358 Denisov, N.G., O vzaimodeistvii neobyknovennoi i obyknoen

noi voln v ionosfere i effekte umnozheniia otrazhennykh sig- nalov. (Interrelation between anomalous and ordinary ionospheric waves and the reinforcement of reflected signals. ) Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki, Moscow, 29(3,

i.e. 9):380-381, Sept. 1955. 4 refs. , 5 eqs. DLC--The usual

and the anomalous ionospheric waves cannot be considered as independent since the media, while inhomogeneous, are not

sharply bounded or separated. Only in the regions far from

the boundary layers can the two types be considered as separate or independent phenomena. Proof of the dependence in

the boundary regions is given mathematically. --M. R.
108

A-359 De Voogt, A. H. , The calculation of the path of a radio-ray

in a given ionosphere. Institute of Radio Engineers, New

York, Proceedings, 41(9): 1183-1186, Sept. 1953. 5 figs. , 6

refs. , 14 eqs. DWB--A third degree function is presented giving in a hypothetical way the electronic density in the ionosphere as a function of height or distance to the earth center;

by inserting appropriate values of the constants, in accordance with measured values from ionospheric sounding stations,

it is possible to arrive at any desired or proposed form of distribution (CHAPMAN, HACKE), though there is no physical

base for this third degree curve given in this paper. This

function allows, after substitution, to calculate exactly, i. e.

,

without any approximation, traveling-time, maximum height,

and distance on the earth's surface reached by a radio-ray

radiated at a given angle. Briefly, the calculation of the raypath in an ionosphere based on measured values and heights

of ionization-maxima at the ionospheric stations and based on

arbitrarily selected values of gradients is shown to be possible. --Author's abstract.

A-360 Dickson, David V. , Nomogram and slide-rule for solution of

spherical triangle problems found in radio communication.

Journal of Geophysical Research, 56(2): 163-175, June 1951.

8 figs. , tables, 3 refs. MH-BH--For prediction of communication frequencies and other ionospheric measurements which

vary with latitude and longitude, a nomogram and slide rule

based on NAPIER 's proportions has been devised and the theory, data, the nomogram and slide rule and examples of their

use are presented. It enables a fix to be made speedily from

bearings taken at two points some distance apart. It is es- pecially valuable where a great circle path intersects the

edge of a polar gnomonic chart and must be carried across to

another gnomonic chart. --M. R.

A-361 Dieckmann, Max, Funktechnische und atmospharisch-elektrische Probleme der Stratospharenforschung. (Radio engineering

and atmospheric -electric problems of stratospheric research.

)

Deutsche Akademie der Luftforschung, Munich, Schriften, No.

46:117-146, Sitzungsperiode 1939/1940, pub. 1941. 17 figs. , table, 12 refs. Discussion p. 145-146. DLC—The atmosphere

is considered as consisting of two layers, from sea-level to

the lower surface of the ionosphere, and the ionosphere. The

wind direction and velocity are obtained from a small transmitter with antenna, carried by a sounding balloon. Heights are determined from the speed of ascent or barometric data. The

radio waves emitted by the transmitter are received by two DFreceivers on the ground which measure the angles between the

radio waves and N. From the position and height of the transmitter at successive times the wind is computed. The most
109

suitable wave length is 10-11 m. The propagation characteristics are discussed theoretically and a formula for the computation of propagation distance, which could be reached under

conditions that the transmitter and receiver are placed in an

open space, is given:

9 55 10 - r - —' ' N , where N - emission intensity, r - diss tance reached, s = required receiving field intensity in —— . Direction finding and DF-receivers net is further discussed.

The second part takes up the atmospheric -electric problems.

Vertical distribution of the electric potential gradients and of

transmission current values is shown on graphs, taken from

EVERLING and WIGAND, up to 9 km. -C. E. P. B. , N. A. Zikeev.

// A-362 Dieminger, W. , Uber Echolautungen der Ionosphare bei Sch- ragen Einfall . (Echo soundings of the ionosphere at oblique

incident. ) Zeitschrift fur Angewandte Physik, (3/4): 90-96,

March 20, 1951. --Review of methods of synchronizing transmitter and receiver for fixed- and variable-frequency working.

Traces recorded using quartz-clock synchronization for pulse

reception and receiver tuning are shown, and results are briefly discussed.

A-363 Dieminger, W. , The scattering of radio waves. Physical

Society of London, Proceedings, Sec. B, No. 64:142, 1951.--

A review of the recent work on scattering draws attention to a number of discrepancies in the interpretation of the data.

Most workers believe that the scattering is due to clouds in

the E layer . The experiments described in this paper indicate

that there are several types of scattering phenomena. It is

concluded that the most common source of scatter is the re- flection of waves from irregularities on the surface of the earth. In this case the wave path is from the sender to F layer--

earth--F layer and hence to receiver, i. e. is analogous to a 2 x F reflection. The characteristics of the different types of

scattering and their effects on the propagation of short waves

are discussed.

// A-364 Dieminger, Walter, Uber die Ursache der excessiven Absorp- tion in der Ionosphare an .Wintortaqen. (On the causes of excessive absorption in the ionosphere on winter days. ) Journal of

Atmospheric and Terrestrial Physics, 2(6):340-349, 1952. 9

figs. , 23 refs. English summary p. 340. DWB--On many winter days echoes are received on 1. 6-4 Mc/sec from 75-90 km

with a regular diurnal variation of height, minimum at noon,

merging with a level of sporadic echoes at 95 km between sunset and sunrise, independent of frequency. The height of the

echoes is closely related to short-wave absorption and they are
no

attributed to partial reflection at sharp boundary of an ionized

region extending downwards from E layer. It is possible that

sporadic night reflection is due to volcanic dust. --C. E. P. B.

A-365 Dieminger, Walter (inst. for Ionosphere Investigation, Hanover, Germany), Origin of ionospheric scattering. U. S. Air

Force. Cambridge Research Center, Geophysical Research

Papers, No. 11:175-194, 1952. figs. , 21 refs. Discussion.

DWB--Deals with occurrence and origin of scattering (scattered echoes) as observed at Lindau during 1947 and 1948. Dividing the echo types into: (1) E-scatter, (2) lF-scatter, (3)

2F-scatter, (4) G-scatter, author discusses each type in some

detail. The 2F type is due to ground irregularities, and is present regularly, the other types only under suitable ionospheric

conditions. --W. N.

A-368 Dieminger, W. , Ein neuer Ausbreitungsweg fur Ultrakurzwel - len liber gross e Entfernungen. (A new way of transmitting ultra short waves to great distances. ) Umschau, 54(4):118-119,

Feb. 15, 1954. DWB--Range of ultra-short waves is increased

about 1/3 by refraction which varies with pressure, temperature and water content in lower atmosphere. Very abnormal

ranges are due to reflection at ionosphere. This has been achieved regularly (up to 2000 km) in America by a special technique; the cause is discussed. --C.E. P.B.

A-36'7 Dieminger, Walter, Neue Erkenntnisse liber die Entstehung

der Streustrahlung bei Kurzwellen und ihre praktische Bedeu- tung. (New knowledge of the scattering of short waves and

its practical importance. ) Umschau, 54(10): 300-303, May 15,

1954. 6 figs. , 9 refs. DGS--An account of results of recent

research at Lindau/Harz and Stanford Univ. , California, with

diagrams of reflection at F layer and scattering at earth's sur- face or occasionally at sporadic E layer. Scattering is mainly

due to irregularities of earth's surface. Echo soundings can

explore the ionosphere not only directly above the transmitter

but for some thousands of km around it. --C. E. P. 3.

A-368 Dieminger, Walter (Inst, ^ur Ionospharenforschung Max-Planck

-Gesellschaft, Lindau), Uber die Wirkung solarer Korpuskeln

in der Ionosphere . (Changes in the jonosphere from solar cor- puscles. ) Archiv der Elektrischen Ubertragung, Stuttgart, 8

(6):259-268, June 1954. 16 figs. , 32 refs. English summary

p. 259. DLC--The paper discusses typical changes occurring

in the ionosphere during the penetration of solar corpuscles

inside and outside the zone of northern lights. This is followed by a report on an extension of the theory of CHAPMAN - FERRARO by MARTYK that allows the observed phenomena in

the ionosphere and in terrestrial magnetism to be explained in
121

the same basic manner. The essential idea is here that the

corpuscles emitted from the "ring current" transfer the radial

field of polarization of this current to the zone of northern

lights. The meridional electrical field set up there brings cur- rent systems into motion and modifies as a secondary effect

the distribution of the charge carriers in the F2 layer. --Author's abstract.

A-369 Dieminger, Walter, Short wave echoes from the lower atmosphere. (In: Physical Society of London, Physics of the Ionosphere, Pt. 1. The lowest ionosphere. London, Physical Society, 1955.

A-370 Dieminger, W. , Das Internationale Geophysikalische Jahr,

HI, Die Plane der Ionospharenforschung. (The I. G. Y. , Pt. 3,

The plan of ionosphere investigation. ) Umschau, 57(5): 132-

134, March 1, 1957. 2 figs. DLC--More than 200 stations are planned to investigate ionosphere during IGY, forming a wide

network along geomagnetic equator, strips on 70 W, 10 E and

150 £, and special networks in auroral zones in Canada and

Antarctica. German program is described. --C. E.P. B.

A-371 Dieminger, W. ; Moeller, H. and Rose, G., Long-distance

single F-hop transmission. Journal of Atmospheric and Terrestrial Physics, 13(1/2): 191 -192, Dec. 1958. 5 refs. --Observation of the high angle ray of single F-hop beyond the limiting distance of the ray radiated tangentially with the earth was

predicted in 1955 by Dieminger and Moeller. This is a brief

report on observations supporting their theory. --W. N.

A-372 Dieminger, Walter E (Max-Planck Inst, for Aeronomy), Clouds

in the sporadic E-layer. Annales de Geophysique, Paris, 15

(l):23-30, Jan. /March 1959. 8 figs. , 24 refs. French summary

p. 23. DLC--The sporadic E layer with its drifting clouds is

still an unsolved problem of the ionosphere. Several questions are discussed here. To explain the fact of transparency,

the hypothesis fitting best the bulk of observations is that of a nebulous structure of the Es layer. Horizontal extension,

development and drifting away of these banks of clouds are studied. Finally, the possible origins of auroral E and sporadic E in moderate and equatorial latitudes are discussed. Auroral E seems to be produced by solar corpuscles penetrating as low as 100 km, or by radiation (probably X-rays) produced by

the solar particles at greater heights. The release of energy

stored during daytime by dissociation or ionization seems to

be the most probable origin of sporadic E. --A. V.
112

A-373 Dieminger, W. ; Moiler, H.G. and Rose, G. , Further results

of sweep-frequency oblique incidence pulse transmissions.

Journal of Atmospheric and Terrestrial Physics, 14(1/2): 179-180,

April 1959. 2 figs. DLC--Brief report on results of experiments by sweep-frequency oblique incidence pulse over N.

European 2000 km path. It is shown that omission of Fl re- flections gives (not the true distorted) propagation conditions.

Preliminary conclusion that strong variations of F2-MUF are caused by variations of virtual height (probably because of Fl

retardation) rather than by changes of critical frequency will

be analyzed in detail. --W. N.

A-374 Dieminger, Walter, Transient fine structure of the E-layer.

Journal of Atmospheric and Terrestrial Physics, 16(1/2) :179,

Oct. 1959. DLC --Routine ionograms as obtained at Lindau

(uber Northeim, Hannover) since 1950 show a complicated

fine echo structure between foE and fminF2 varying from one

record to another. In anticipation of detailed analysis it is

suggested: 1) variation of virtual height of the intermediate

echoes are due to varied retardation controlled by electron

density within the stratification; 2) the multiple structure of

the retarded F2 trace may be explained by vertical and offvertical reflections. --W. N.

A-375 Dinger, Harold E. (Naval Research Lab. , Wash., D. C. ), Report on URSI Commission IV Radio noise of terrestrial origin . Institute of Radio Engineers, Proceedings, 46(7): 1366-1372,

July 1958. Also in: National Research Council, Publication

No. 581:102-114, 1958. DWB, DLC -Commission IV deals with

study of sources, propagation and effects of atmospherics,

whistlers, dawn chorus and other VLF emissions of natural

origin. Nine sessions were held, dealing with whistlers and

other VLF emissions, use of atmospherics to investigate propagation phenomena, IGY projects, atmospheric sources, characteristics of noise and relation between source and atmospheric. These subjects are discussed and 6 resolutions on var- ious aspects presented in detail. --M. R.

A-376 Dinger, Harold E. , A four-year summary of whistler activity

at Washington. D.C. Journal of Geophysical Research, 65(2):

571, Feb. 1960.

A-377 Dokuchaev, V.P. , O vliianii magnitnogo polia Zemli na vetry

v ionosfere. (Effect of the earth's magnetic field on ionospheric winds. ) Akademiia Nauk SSSR, Izvestiia, Ser. Geofiz.

No. 5:783-787, 1959. 16 refs. , 19 eqs. DWB, DLC--The author shows that in the theoretical interpretation of winds above

100 km it is necessary to take into account possible deviation

from the geostrophic wind associated with the action of electro-
113

magnetic forces. The relationship between electrodynamic

and hydrodynamic processes in the ionosphere is established

by the action of the magnetic field of the earth upon the induction current arising during the movement of the conducting medium within this field. In magnetic hydrodynamics, for a medium posessing electrical conductivity, the equations of NavierStokes include the total electrodynamic force. If Coriolis force and the force of gravity are added then the equations assume

the form _ r

. -22U(w; v - -£ +

J e

[ J * R,] - * + 2[*vpv

where and - velocity and density of the medium respectively; v - kinematic viscosity; g - acceleration of gravity;

w - angular rotation of the earth; H - magnetic field of the

earth; j - density of the electric current. In case of an anisotropic medium the generalized ohm's law for an incompletely

ionized gas is written as j= «i(k'h.)h8 + i Di xE']*i».+ *»[*••*£'[

where E - potential of the electric field, h - unit vector of

the magnetic field and CTq^O" and Cz are parallel conductivity,

transverse conductivity and the conductivity respectively.

On the basis of these expressions the author obtains a simplified system of equations of x, y coordinates,

hH,^) v

*JK

u ^ j_. 9^

dt * f«*/ fe* e 2*

The solution of this system of equations is presented. In the

stationary state the velocity of the wind in the E-layer is given

by Q 3yb IT - - A %£

where

The stationary gradient wind in the F-layer is given by

--I.L.D.
114

A-378 Dolukhanov, M.P. , Rasprostranenie radiovoln. (Radiowave

propagation. ) Moscow, Gosud. Izdatvo Literatury po Voprosam Sviazi i Radio, 1952. 490 p. refs. , numerous figs. , tables, and eqs. DLC )QC66l.D6)--A textbook on radio propagation, going quite extensively into surface propagation, ionospheric propagation (p. 145-245), long wave, short wave, and

ultrashort wave propagation and, finally, atmospherics and

cosmic noise. Tropospheric meteorological factors are discussed on p. 436-461, in the chapter on ultrashort wave propagation. Theory, curves, etc. are given for humidity and

temperature effects, channels and turbulent dispersion, absorption and beyond-the -horizon propagation. --M. R.

A-379 Dominic i, Piero, Sulla misura dell' ass orbimento ionosferico . (Measurement of the ionospheric absorption. ) Annali di Geofisica, Rome, 5(4):561-568, Oct. 1952. 2 figs. , English summary p. 568. MH-BH--Methods of ionospheric absorption measurement developed since APPLETON (1925) are briefly reviewed. The basic principles of two groups of such methods (the

method of the continuous wave and the pulse method) are ex- plained. An installation for absorption measurement to be

established near Rome by the Istituto Nazionale di Geofisica

is announced. It will consist of a 3-Mhz transmitter and a synchronized receiver placed 10 km from the transmitter. Transmission will be disrupted every 10 minutes for the purpose of

identifying interference and disturbances. --G. T.

A-380 Dowden, R.L. and Goldstone, G. T. , "Whistler mode" echoes

from the conjugate point . Nature, London, 183(4658): 385-386,

Feb. 7, 1959. fig., 3 refs. DLC --Whistler mode transmission

experiments were conducted from Tokyo, Japan to check the

Eckersley-Storey theory "that whistler mode signals from Tokyo

would return to the earth's surface at a point near Darwin, Northern Territory, some 3500 km from Hobart. They apparently

did, and the 0. 2 sec delay was found in agreement with the

geomagnetic latitude. --W. N.

A-381 Drachev, L.A. and Berezin, U. V. , (The effect of large inhomogeneities in the F2-layer on the reflection coefficient of

radio waves. ) Radiotekhnika i Elektronika, 2(10): 1234-1239,

Oct. 1957. In Russian.

A-382 Driatskii, V. M. and Besprozvannaia, A. S., Ionospheric

conditions in the circumpolar region. Annales de Geophysique, Paris, 14(4) :438-455, Oct. /Dec. 1958. 13 figs. , 11 photos, 3 refs. DLC --Ionospheric observations from the drifting

station SP-3 during the period May 15, 1954 to April 14, 1955,

and especially observations made during the Arctic night, are given. The authors give a short description of the character-
T -6 f~» liO

istics of the apparatus and of the magnetic field state. The

results of the observations are given for the normal E layer,

the Es sporadic ionization, the E2S sporadic ionization, the

normal Fl and F2 layers and the anomalous absorption of radio

waves. Of greatest interest are the results received under the

conditions of the Arctic night in connection with the F2 layer.

The critical frequency for F2 layer during this period was unexpectedly high, reaching 5-6 mc at times. The evident sporadic

type of the layer being expressed in the sharp change of the

critical frequency in the layer from hour to hour and from day

to day, a definite connection with the state of the magnetic

field proves its corpuscular nature. At the same time, the

distinct shape of height-frequency diagrams, normal for re- flections from the F2 layer, stipulated by a wave radiation,

can hardly be taken to agree with the corpuscular conception.

It is still impossible to solve the problem of the nature of observed high ionization in the F2 layer during a Polar night. -- A.V.

A-383 Drummond, J. E. , The connection between ionospheric patterns and field strengths reflected on the ground . Journal of

Atmospheric and Terrestrial Physics, 9(5/3): 282 -294, Nov.

1956. 3 figs. , table, 8 refs. , eqs. DWB--H the ionosphere

is regarded as a plane, patchy reflector, it can be shown by

using Doppler shift theory and wave theory that drift and turbulent processes with periods less than A /2 sin oi ( A is

the radio wavelength and 2 a is the angle subtended by the

reflecting area on the ground) do not produce patterns on the

ground and other short-length processes are attenuated. The

correlogram of the reflected signal is also correspondingly

modified, and some ionospheric observations are examined in

the light of this theory. --Author's abstract.

A-384 du Castel, Francois; Misme, Pierre and Voge, Jean, Reflexion d'une onde 61ectromagnetique par une couche d' atmosphere

presentant une variation de l'indice de refraction. (Reflection of an electromagnetic wave on an atmospheric layer having

a variation of the refractive index. ) Acad^mie des Sciences,

Paris, Comptes Rendus, 246(12): 1838-1840, March 24, 1958.

DLC--More general formulation of the reflection coefficient,

which may be interpreted as an increasing function of the atmosphere thickness where great stability prevails, is presented. -A. V.

A-385 Dumont, Rene, L 'ionosphere et l'optique geometrique des

ondes courtes . (The ionosphere and the geometric optics of

short waves. ) Paris, Dunod, 1958. 100 p. 33 figs. , 11 refs.

(Monographies Dunod, No. 3. ) DWB (M10. 535 D893io), DLC

(QC879. D85). Review in La Meteoroiogie, Paris, Ser. 4, No.

49:75, Jan. /March 1958. --
116

A pocket-size textbook giving basic and up-to-date information on the ionosphere and its formation, structure, radio

wave propagation, sounding by vertical pulses and by study

of photochemistry, absorption, geomagnetic fluctuations, optical phenomena, meteors and rockets. Characteristics of the

different layers, applications to long-distance radio, propagation, forecasting of ionospheric and radio propagation conditions, etc. are discussed. Aurora, airglow, sunspots, satellites, ionospheric tides and various theories are treated incidentally. Numerous schematic diagrams, an author and sub*

ject index are included. --M. R.

A-386 Duncan, R.A. (Radio Res. Labs., Commonwealth Sci. &

Industrial Res. Organiz. , Australia), Computations of electron density distributions in the ionosphere making full allowance for the geomagnetic field . Journal of Geophysical Research, Wash., D.C., 63(3]1:491 -499, Sept. 1958. 3 figs.

,

13 refs. , 18 eqs. DLC --JACKSON 's method of computing electron density distributions from h'f records has been modified

slightly and adapted for use on an electronic computer. Reduction of a single h'f record takes about 20 sec of computer

time. The method makes allowance for the geomagnetic field

and is exact save for the uncertainty about the electron density between ionospheric layers which is inherent in the method of pulse sounding from the ground. Rocket measurements

(SEDDON et al. , 1954) enable a reasonable resolution of this

uncertainty. Some examples of electron density distribution

at Brisbane are given. It is shown that the night-time distributions are much closer to the Chapman than the parabolic

form. This is to be expected (Martyn, 1956) in a region in

which the electron distribution is determined by the opposing

processes of downward diffusion under gravity, and a height

gradient of electron decay. The effect of geomagnetic disturbance on the day and night electron density profile is illustrated and discussed. --Author's abstract.

A-387 Dungey, J. W. , Electrodynamics of the outer atmosphere . Pennsylvania. State Univ. Ionosphere Research Laboratory,

Contract AF 19(122) -44, Scientific Report, No. 69, Sept. 15,

1954. 52 p. refs. , p. 52. , eqs. MH-BH--Because of relative motion between the Earth and the interplanetary gas the

geomagnetic field is confined to the inside of a ChapmanFerraro cavity. The physics of the charged particles and electromagnetic field inside this cavity, but above the ionosphere,

is studied. Their static condition is described by isothermal

diffusive equilibrium and hydrogen is predominant. STOREY's

value of the electron density is adopted. The dynamics of the

outer atmosphere may be described in terms of ALFVEN waves.

The normal modes of oscillation are discussed and it is also
117

shown that travelling waves must be generated at the outer

surface, because of the motion of the interplanetary gas.

The possible applications of this study to geomagnetic micropulsations and to travelling disturbances in the ionosphere

are considered. --Author's abstract.

A-388 Dungey, J.W. , Propagation of Alfven wave through the ionosphere. Pennsylvania. State Univ. Ionosphere Research Laboratory, Contract AF 19(122) -44, Scientific Report No. 57, Feb.

15, 1954. 19 p. table, 4 refs. , 22 eqs. DWB--As a preliminary to a study of micropulsations, it is necessary to investigate the propagation of Alfven waves through the ionosphere.

General results are obtained for waves travelling parallel to

the magnetic field, and approximations are then made, which

are valid for periods of the order of a minute. Numerical values are given for the ionosphere and results are given for the

simple case when the magnetic field is vertical. An approximate discussion is also given of waves propagated obliquely

to the magnetic field. --Author's abstract.

A-389 Dungey, J. W. (A. W. R. E. , Aldermaston Berkshire, England),

Effect of a magnetic field on turbulence in an ionized gas . Journal of Geophysical Research, Wash., D.C., 64(12):2188-

2191, Dec. 1959. fig., 24 eqs. DLC- -The problem is formulated using the equations of motion for each constitutent of

the gas. Approximations are discussed, and idealizations

are adopted appropriate to the ionosphere. A physical picture

is given for the generation of irregularities in electron density

by shear flow in the neutral air. Given the motion of the air,

the electron density can be calculated, and this calculation

is carried out in the linear approximation for an arbitrary Fourier component. --Author's abstract.

A-390 Dyce, R. B. , Studies on propagation in the ionosphere. Cornell Univ. School of Electrical Engineering, Research Report

EE 209, 1954. --The author of the body of this report, R. Dyce,

has for the past two years been recording signals received at

Ithaca from transmitters located at Cedar Rapids, Iowa. These

transmitters have been operating continuously, radiating CW

at frequencies of 49. 6 and 49. 8 mc/sec in connection with

another experiment. During the period a study has been made

of the times when these signals have been received here by

auroral and sporadic E propagation. From this data curves are

in surprisingly good agreement with those obtained by visual

observations. The Sporadic-E curves are consistent with other

radio observations of this phenomenon. Rough measurements

of the distribution of signal strengths have also been made.
118

// A-391 Ebert, W. ; Ehlers, H. ; and Dobiasch, R. , Ubersicht uber

den Stand der Arbeiten der Union Europeenne de Raiiodiffusion (UER) liber die Ionospharische Ausbreitung der Lang und

Mittelwellen. (Review of the European Broadcasting Union's

works. Ionospheric propagation of long and medium waves. ) Rundfunktechnische Mitteilungen, 3(5):205-, 1959. --The purpose of the work which started Oct. 1952 was to establish

generally recognized curves of the nocturnal propagation. Description of measuring methods and statistical evaluation procedures given here include initial results of some all-night re- cordings and comparison with available data elsewhere. --W.N.

A-392 Elliott, G.L. and Weller, R. , Some navigation problems at a guided missile range . Navigation, Los Angeles, 4(4):145-151,

Dec. 1954. 4 figs. , eqs. DWB--Discusses problems connected with the operation of guided missile ranges in general and

the Point Mugu, Calif. , sea test range in particular. Radio

wave propagation effects, gravity anomalies, aerology and

wind effects are among the problems mentioned in connection

with navigational, tracking and plotting operations. --G. T.

A-393 Ellis, G. R. , Angle of arrival of Z echoes . Nature, London,

171(4345): 258-259, Feb. 7, 1953. fig., ref. DLC--Measurements made at Hobart (mag. lat. 51 S) during July-August 1952

on 4. 65 Mc/s to test SCOTT's hypothesis that the weak third

F2 penetration frequency (Z mode) observed at high magnetic

latitudes is due to longitudinally propagated waves reflected

from an area near the magnetic zenith. The Z echo reflection

height was 170-210 km, and mean direction 7. 8 N of the vertical in the magnetic plane. These results are inconsistent with

the collisional frequency required on SCOTT's theory. --Physics

Abstracts, No. 3771, 1953.

A-394 Ellis, G. R. , F-Region triple splitting. Journal of Atmospheric and Terrestrial Physics, 3(5):253-259, June 1953. 7 figs.,

2 tables, 8 refs. MH-BH--Measurements of the direction of

arrival of Z echoes have been made at Hobart, Tasmania. The

results indicate that F-region triple splitting is caused by

back scattering from a rough layer. The directions observed

are consistent with the assumption that reflection at the Z

level occurs when the angle of incidence is such that the wave

normal becomes parallel to the geomagnetic field at the ordinary level of reflection. --Author's abstract.

A-395 Ellis, G. R. , On the propagation of radio waves through the

upper ionosphere. Journal of Atmospheric and Terrestrial Physics, London, 9(l):51-55, July 1956. fig., 2 tables, 7 refs. , 7 eqs. DWB-
119

Since it is likely that electron densities of more than 0.

electron per cm3 exist at distances of several thousand kilometres from the earth, the propagation of the two low -frequency extraordinary modes through the ionosphere is improbable.

Of the five possible ways in which waves can penetrate the

lower ionosphere, we therefore have only three which can also

penetrate the upper ionosphere. Of these three, the oblique

longitudinal ordinary mode can produce only second-order

observational effects in the absence of strong discrete sour- ces of extra-terrestrial radiation, since its angular range is

only about 1 degree (ELLIS, 1956). The low -frequency limit

for the observation of cosmic radio emission will, therefore,

in general be that given by foF2, and the observation of these

radiations from below the ionosphere is unlikely at frequencies much less than 1 Mc/s. --Author's conclusion.

A-396 Ellis, G. R. , The Z propagation hole in the ionosphere.

Journal of Atmospheric and Terrestrial Physics, 8(l/2):43-54,

Feb. 1956. 7 figs. , 2 tables, 8 refs. , 4 eqs. DWB--The oc- currence of F region triple-splitting allows us to examine ex- perimentally the properties of an unusual propagation hole in

the ionosphere. Two methods of estimating the angular size

of the hole are discussed. The first is based on the beam effect of Z echoes, according to which Z echoes are returned to

the ground in a narrow beam. The second follows from an

analysis of the distribution of angle of arrival of Z echoes.

It is found at Hobart, with a wave frequency of 4.65 Mc/s,

the hole is approximately circular with an angular width to

half-power points of less than 0. 84 . Under certain circumstances the propagation hole provides a means by which waves

can pass completely through an otherwise reflecting ionospheric

layer. --Author's abstract.

A-397 Ellis, G. R. A. , Directional observations of 5Kc/s radiation

from the earth's outer atmosphere. Journal of Geophysical Research, 65(3): 839-843, March 1960. 3 figs. , 2 tables, 5refs.

DLC—Low -frequency radio noise burst were observed by an

Australian network of direction finders Sept. -Oct. 1959. Tabulated recordings and facsimilies are presented featuring bursts

from sources in 40 - 50 lat. between 135° and 155° E long.

Scanning of the projected world image by a satellite-borne 5

Kc/s receiver is suggested. --W. N.

A-398 Ellyet, C. D. , Echoes at D-heights with special reference to

the Pacific Islands. Terrestrial Magnetism and Atmospheric

Electricity, 52(1):1-13, March 1947. 3 figs. , 2 tables, 22

refs. DLC--Frequency range, diurnal and seasonal variations

and echo strengths are analyzed and compared with those taken

during 1944 and 1945. --W. N.
120

A-399 Ellyett, CD. and Leighton, H. , Solar cycle influence on the

lower ionosphere and on VHF forward scatter. Institute of

Radio Engineers, N. Y. , Proceedings, 46(10): 1711 -1716, Oct.

1958. 4 figs., 2 tables. DLC--A brief survey of published

literature indicates that the electron concentration in the Dregion of the ionosphere changes with the solar cycle. Such

changes should also be apparent in the VHF forward scatter

signal intensities. Analyses have therefore been made of

seven years' results, at 4S. 8 mc from the Cedar Rapids, Iowa,

to Sterling, Va. , forward scatter path (1243 km). On an an- nual basis, it is found that the monthly median received signal intensity, for the noon and afternoon period only, follows

the same trend as the mean monthly sunspot number. The effect is still more pronounced when comparison is made with

magnetic disturbance indexes. However, when the comparison with magnetic indexes is made using a direct comparison

in each 3-hr period, and eliminating long-term trends, no observable increase of the signal intensity is found as the magnetic conditions become disturbed. This is in sharp contrast

to the behavior of such circuits in auroral regions. Further

analysis shows that a weak increase in signal intensity with

a rising magnetic index does occur if the analysis is confined

to the midday period. It is concluded, therefore, that any

magnetic influence is smaller on middle than on high latitude

scatter circuits, but an effect can be clearly discerned by

studying the magnitude of the received signal through a solar

cycle. These results show that VHF forward scatter signals

are not caused by the reflection from meteor trails alone. -- Authors' summary.

A-400 Ellyett, CD. (U. Canterbury, Christchurch, New Zealand)

and Watts, J. M. , Stratification in the lower ionosphere.

U. S. National Bureau of Standards, Journal of Research, Sec.

D, 63(2): 117-134, Sept. /Oct. 1959. fig., 2 tables, 149 refs.

DWB, DLC--A survey of the evidence for stratification in the

ionosphere below 100 km is given, covering radio and optical

observations, and rocket measurements. The conclusion is

reached that one stratum at about 85 km is observed consistently, and that other fine structure exists but has no long

time constancy of height or pattern. There is no series of

preferred heights below 100 km. The authors consider explanations which may account for the observations, and advocate

the testing of radio methods of exploration in conjunction with

rocket measurements in order to develop the most practicable

means of obtaining accurate electron density versus height

profiles on a synoptic basis. --Authors' abstract.
121

A-401 Engel, Leonard, Mystery of the air we explore. New York

Times Magazine, Section S, April 15, 1956. p. 27, 62-64.

illus. DLC--A popular article on the structure, composition

and methods of exploring the atmosphere, especially in the

highest layers (by ionospheric radio sounding, rockets, satellites, etc.). The jet stream is also discussed and a cross- section showing atmospheric structure to 800 mi and various

sounding devices presented. --M. R.

A-402 Eshleman, V. R. , Theory of radio reflections from electron- ion clouds . Institute of Radio Engineers, Professional Group

on Antennas and Propagation, Transactions, Vol. AP-3, No. 1: 32-39, Jan. 1955. Also issued as Stanford University, Electronics Laboratories, Contract N6 onr 251(07), Report No. 72,

Dec. 1, 1953.

A-403 Etzweiler, G. A. and Schmerling, E. R. , Measurements of

the vertical incidence ionospheric absorption at 75 Kc/s.

Pennsylvania. State Univ. Ionosphere Research, Contract AF

19(604) -1304, Scientific Report No. 109, Aug. 15, 1958. 125 p.

4 figs. , 8 refs. , 5 eqs. (Appendix: 112 p. of tables) DWB—

(M10. 535 P415i)--The results of measurements of the absorption of radio waves at vertical incidence at a frequency of 75

kc/s are presented. The measuring techniques and equipments are described. The data are presented as diurnal plots

of absorption for the period from Oct. 1, 1955 through April 25,

1957 and as monthly means for the interval Oct. 1955 through

April 1957. --Authors' abstract.

A-404 Ewing, R. A. , The determination of upper winds by electronic

means. Sixth New Zealand Science Congress 1947, Proceedings, Royal Society of New Zealand, Transactions, 77(5): 76-

78, Nov. 1949. DLC--Discusses advantages and disadvantages of British and U. S. radio-direction finding methods and

New Zealand microwave radar. The 700 and 900 megacycle

pulse repeater is considered most accurate. --C. E. P. B.

A-405 Ewing, R.A., Use of radar as an economical means of ob- taining upper wind data. New Zealand. Meteorological Service,

Technical Note, No. Ill, March 19, 1954. 7 p. 8 tables. Attached, Addendum, No. 1, 1954. Figures for tables shown in

the note. 1 p. DWB—The economics of wind finding by primary radar and light-weight balloon-borne reflectors are discussed. The performance figures for the type ME 7 radar used

by the N.Z. Meteorological Service are quoted. It is concluded that the system can meet the needs of most services where

temperature soundings are not required to accompany each upper wind measurement. --Author's abstract.
122

"

a <i A-406 Fanselau, Gerhard, Uber die Stoning der Ionosphare vom 24 - 26 Januar 194S. (On the disturbance of the ionosphere from

January 24-26, 1949.) Zeits chrift fur Meteorologie, 3(4):100-

110, April 1949. 6 figs. , 5 tables. DWB--On Jan. 21st two

large spots approached central meridian of sun. A magnetic

storm began on Jan. 24th and is described in detail. Reception of the 1, 250 m space radio wave from Kalundborg showed

great variations. 27-day recurrences are clearly shown in

Potsdam magnetic character figures from Dec. to March. Associated auroras on Jan. 24-26 are listed and described. -- C E. P. B.

A-407 Farley, D.T. , Jr., A theory of electrostatic fields in the ion- osphere at nonpolar geomagnetic latitudes. Journal of Geophysical Research, 65(3):869-877, March 1960. 9 figs., 7

refs. --This theoretical examination shows that coupling between the dynamo region and the F-region will be stronger at

the poles, weaker at equator and can appear at all latitudes.

Strength of the electric source field as produced by an irregular, horizontally stratified wind in the dynamo region is computed and the brief examination as to whether electrostatic

fields may cause electron density variations in the F-region

was negative.

A-408 Fedorova, L.N., Ionosfera i ee znachenie dlia radiosviazi.

(Ionosphere and its importance in radio communication. ) Meteorologiia i Gidrologiia, No. 2:57-58, March/April 1955. DLC

--In this brief note, the author describes the composition and

characteristics of the ionosphere, the study of the ionosphere

by the analysis of radio signal, the characteristics of the var- ious ionospheric layers and their relationship to radio propagation. —I. L. D.

A-409 Feinstein, J. (Natl. Bureau of Standards, Wash., D. C. ), Higher order approximations in ionospheric wave propagation.

International Council of Scientific Unions. Mixed Commission

on Ionosphere, Brussels, Sept. 1950. Proceedings, pub. 1951.

p. 207-215. 12 eqs. DWB--Lengthy solution of theory of wave

propagation in ionosphere shows that although the higher order

terms produced by non-linearity of medium are negligible in

the absence of resonance, the ionosphere cannot be considered as a simple anisotropic medium which can be represented

by a tensor type dielectric constant, or in other words a charged medium cannot be reduced to one that is passive. --From

author's abstract.
123

A-410 Feinstein, J. , Ionospheric wave propagation at low frequen- cies. International Council of Scientific Unions. Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings,

pub. 1951. p. 166-175. 3 figs. , 3 refs. DWB--Theoretical

and empirical comparison of wave theory and ray theory for

propagation and reflection in a geomagnetic field. A true

wave theory, not a ray or even a modified ray theory, is held

to be the only reliable approach to solution of the observed

characteristics of the ionosphere. --M. R.

A-411 Fejer, J. A. , The diffraction of waves in passing through an

irregular refracting medium. Royal Society of London, Proceedings, Sec. A, 220:455-471, 1953. --A relation is derived

between the angular power spectrum of waves emerging from

a thin diffracting screen random in two dimensions and the

auto-correlation function describing the irregularities of the

field as it emerges from the diffracting screen. The special

case of an isotropic screen characterized by an auto-correlation function which depends only on distance and not on direction is discussed for normal and oblique incidence. Multiple scattering of waves caused by volume irregularities of

the dielectric constant is considered. The angular power spectrum and the auto-correlation function describing the irregularities of the diffraction field caused by multiple scattering in a thick slab are determined. The results are compared with

those obtained by Hewish for a thin phase --changing screen. The results are discussed in terms of problems arising in the

study of radio-wave propagation.

A-412 Fejer, J. A. , The interaction of pulsed radio waves in the ionosphere. Journal of Atmospheric and Terrestrial Physics, 76

(6):322-332, Dec. 1953. 4 figs. , 13 refs. , 19 eqs. DWB--It

has been established that radio-wave interaction between pulsed radio waves with frequencies of the order of 2 Mc/s takes

place above the Transvaal during the day at heights of about

70-90 km. The use of this effect appears to be a promising

method of exploring the lowest regions of the ionosphere. The

results of the present observations support, for the case of

small excess electron energies, the original form of the BAELEY-MARTYN (1934, 1935) theory of radio-wave interaction

rather than the modification suggested by HUXLEY (1953). The

results for the collision frequency appear to agree well with

those of other workers. —From author's abstract.

A-413 Fejer, J. A. and Vice, R. W. (both, Nat. Inst, for Telecommunications, Res., Johannesburg, So. Africa), The use of

full-wave solutions in the interpretation of ionospheric absorp- tion measurements . Journal of Atmospheric and Terrestrial

Physics, N.Y. , 16(3/4): 307-317, Nov. 1959. 5 figs. , 15 refs. , 13 eqs. DWB,DLC-
124

A numerical method is developed for solving the equations of

ionospheric wave propagation for vertical incidence. The method, which neglects coupling, is used for the calculation of ionospheric absorption. The absorption is first calculated in the

usual manner by using the Appleton-Hartree formula and integrating up to the theoretical height of reflection. A "full-wave"

correction to this result is then obtained from a step-by-step

integration of the wave equation. The thickness of the region,

for which this integration has to be carried out, is only a few

free space wavelengths, and therefore, the additional time re- quired for the calculation of the "full-wave" correction is relatively short. Numerical examples show that for frequencies

of about 2 Mc/s this correction cannot be neglected. The

method is applied in a preliminary interpretation of observed

values of absorption. It is concluded that more than half of

the observed absorption occurs less than 2 km below the theoretical height of reflection. --Authors' abstract.

A-414 Fejer, J. A. and Vice, R. W. (both, Nat. Inst, for Telecommunications Res. , Johannesburg, S. Africa), An investiga - tion of the ionospheric D-region. Journal of Atmospheric and

Terrestrial Physics, N. Y. , 16(3/4) :291-306, Nov. 1959. 11 figs. , 8 refs. DWB, DLC--Two previously described methods

of ionospheric investigation, the observation of weak echoes

from the D -region (GARDNER and PAWSEY, 1953) and the measurement of ionospheric wave interaction (FEJER, 1955), are used to determine tentative profiles of electron density and

collision frequency for the ionosphere below about 35 km. -- Authors' abstract.

A-415 Fejer, J. A. (Defense Res. Telecommunications Establishment, Ottawa, Canada), Electrodynamic stability of a vertically drifting ionospheric layer. Journal of Geophysical Research, Wash., D.C., 64(12) :2217-2218, Dec. 1959. fig.,

2 refs. , 8 eqs. DLC--The electrodynamic stability of a vertically drifting ionospheric layer is examined under certain

simplifying assumptions. No evidence of instability is found.

--Author's abstract.

A-416 Fennel, Perry, Winds in the ionosphere indicated by radio re - flecting "clouds" of high ionic density. American Meteorological Society, Bulletin, 25:371, Nov. 1944. DLC-This brief ex- cerpt from "Somewhere in India", Feb. 12, 1944, reports an observation of constant air currents at about 110 km elevation of

approximately 100 km per hour. --W. N.
125

A-417 Ferraro, A. J. , Experimental and theoretical investigations of

the low frequency polarization at 60, 75 and 150 kc/s. Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF

19(604) -4563, Scientific Report No. 121, July 31, 1959. 96 p.

55 figs. , 2 tables, 15 refs. , eqs. DWB (M10. 535 P415i)--The

instrumentation for recording the state of polarization of 50

kc/s and 75 kc/s echoes for vertical incidence radio soundings

is described in detail. Basically, the equipment resolves the

polarization ellipse into its two circularly polarized components: the ordinary and extraordinary modes. The results of

thirteen months of recording in the intervals of Dec. 1S56 to

April 1957 on 75 kc/s and Oct. 1957 to May 1958 on 60 kc/s

are presented as monthly averages. In addition, a few typical daily curves of polarization for magnetically quiet and

disturbed days are discussed. A catalogue of 25 ionospheric

models for which the group height, phase height, absorption,

and polarization have been computed for 60-75 kc/s and 150

kc/s are presented. From this catalogue a sequence of models are selected which adequately explains the "sunrise effect" as observed on 75 kc/s. In addition, a model is found which

explains the average night-time data on 60-75 kc/s and 150

kc/s. --Author's abstract.

A-418 Ferraro, A.J. and Gibbons, J.J. (Ionosphere Res. Lab., Pennsylvania State Univ., Pa.), Polarization computations by

means of the multislab approximation. Journal of Atmospheric

and Terrestrial Physics, 16(1/2): 136-144, Oct. 1959. 6 figs. , 2 tables, 7 refs. , 4 eqs. DWB, DLC -Becker et al. (1951-1958)

discussed a step-discontinuity approximation method for rapidly determining the polarization of low frequency echoes including the effect of collisions and the earth's magnetic field. In

the present paper, the results of this method are compared

with those of a multislab approximation, and it is shown that

the step method yields satisfactory results. For two electron

density profiles (one near critical coupling and one far removed)

the Rydbeck coupling region was subdivided into slabs of uniform media; by matching the fields between adjacent slabs, N-l

simultaneous equations (for N slabs) were obtained. Because

of the complexity of these equations, digital computer techniques were employed to obtain the desired solutions. The rate

of convergence was estimated by using an increasing number

of slab approximations (as high as 10). --Authors' abstract.

A-419 Ferrell, O. P. , Upper-atmosphere circulation as indicated by

drifting and dissipation of intense sporadic-E clouds. Institute

of Radio Engineers, New York, Proceedings, 36:879-880, July,

1948. 7 figs. , 11 refs. DWB--Co-operative research program

was initiated by author in 1947 to study effects of sporadic-E

reflections in the radio amateur band (50-56 Mc). Observations
126

of two sporadic -E clouds show drifts in one case due west

with a speed of 130 m/sec and in the second a northwestward

drift of 40 m/sec. --G. J. E.

A-420 Findlay, J. W. , Measurements of changes of the phase-paths

of radio waves in the ionosphere. Nature, London, 159(4028):

58-59, Jan. 11, 1947. 3 figs. , 3 refs. -A modification of the

pulse method to determine both the magnitude and the sense

of a change of pulses from E and F layers using 150 m and 75

X show an accuracy better than 100 m in path change occurring in some few minutes. An explanation for the change is

offered. --W. N.

A-421 Findlay, J. W. , An investigation of sudden radio fadeouts on

a frequency near 2 Mc/sec. Journal of Atmospheric and Terrestrial Physics, 1(5/6) :367-375, 1951. 2 figs. , 3 tables, 12

refs. , 8 eqs. DWB--Observations on 105 fadeouts were made

on frequencies near 2 Mc/sec"* to determine the height at

which extra ionization is produced during a sudden fadeout.

This height was found less than 101 km with a collision frequency of about 4. 105 sec "*. --A. A.

A-422 Findlay, J. W. , The phase and group paths of radio waves re- turned from region E of the ionosphere . Journal of Atmospheric

and Terrestrial Physics, 1(5/6): 353-366, 1951. 11 figs. , 2 tables, 18 refs. , 14 eqs. DWB--In measuring the daily and seasonal variations of phase paths of radio waves of the frequency

2.4 Mc/sec"' returned from the E layer it is found that the re- sults disagree with those found for Chapman-region. --A. A.

A-423 Fitch, E. , The problem of introducing ionospheric scatter com- munication systems into the European frequency region.

AGARDograph, Paris, No. 26:43-56, July 1957. 9 figs. , table,

3 refs. DWB (629. 1332 N864a) -Radio propagation (at 37. 3

Mc/s) by scatter from the ionosphere or meteor trails, and problems due to interference from local sources, troposphere, meteor trails, sporadic E, F2, etc. both from a scatter system to

other systems, and to a scatter system are discussed. Based

on 1955 studies at Malta and 1956 and 7 from Gibralter or Keflavik to England conclusion is that choice of highest possible

frequency minimizes these interferences and eliminate the F2

layer interference. Examples of types of interference are shown

on records; careful site location (e.g. on a coast backed by a high cliff) will eliminate local interference. Most of the ener- gy will come from meteor trail scatter - some from turbulent

scatter. --M. R. e
127

A-424 Fleming, John Adam, (ed. ), Terrestrial magnetism and electricity. Contributors, J. Bartels and others. (Reprinted with

corrections.) N. Y. , Dover Publications, (1949). numerous

figs. , tables, eqs. Physics of the Earth, v. 8. DLC--An ex- cellent reference work on all aspects of the subject. It contains 12 chapters written by experts in the fields, and a comprehensive bibliography of 1523 refs. in ch. 13. Three chapters particularly applicable to this bibliography are: ch. 9,

Berkner, L. V. , Radio exploration of the earth's outer atmos - phere (p. 439-491). Ch. 10, Hulburt, E. O. , The upper atmos - phere (p. 492-572) . Ch. 13, Harradon, Harry Durward, Bibliographic notes and selected references (p. 679-778). Section D of the bibliography (p. 749-758) contains 183 references

to works on the ionosphere. The bulk of the material was published in the 1920's and I930's.--M.L. R.

A-425 Florian, Endre, Radiohullamok az ionoszferaban. (Radio

waves in the ionosphere.) Termeszet es Tarsadalom, Budapest, 115(6) :355-359, June 1956. photos, diagrs. DLC--The

role of various atmospheric layers in the propagation of radio

waves of different lengths is discussed; the geometry of ionospheric reflection is explained with the help of schematic diagrams. Since 1955 regular hourly measurements of ionospheric

parameters have been made at Budapest (height and density of

ionospheric layers, etc.). Ionospheric research activities in

Hungary are being conducted with two objectives in mind,

namely (a) to determine (and soon to forecast) radio propagation conditions and (b) to find relationships between ionospheric anomalies, temperature variations, etc. and weather development in the lower atmospheric layers. --G. T.

A-426 Forsgren, Sven K. H. , Some calculations of ray paths in the

ionosphere . Gothenburg, Sweden. Chalmers Tekniska Ho'gskola, Handlingar, No. 104, 1951. 22 p. graphs, diagrs.

,

refs. Price Kr. 3. (Gothenburg, Sweden. Chalmers Tekniska Hogskola, Research Laboratory of Electronics, Report

No. 17. ) DWB--Due to earth's magnetic field, waves in the

ionosphere deviate horizontally. Purpose of this paper is an

attempt to calculate the magnitude of the different deviations

of waves. During ionospheric disturbances, when large horizontal gradients of electron density occur, the phenomenon

becomes more marked. The site of Kiruna is favorable for

these studies. Results are presented in elaborate diagrams

and approximate theory developed for the refractive index and

deviations at vertical incidence. --W. N.
128

A-427 Forsterling, Karl and Wuster, Hans -Otto, Uber die Entste - hung von Oberwellen in der Ionosphare. (Generation of higher

harmonics in the ionosphere. ) Journal of Atmospheric and Terrestrial Physics, 2(1) -.22-31, 1951. 5 refs. , eq. English summary p. 22. DWB--It is shown, in continuation of earlier work

on the propagation of plane electromagnetic waves in an inhomogeneous stratified medium, that the strength of the electric

field parallel to the plane of incidence shows a singular point

near a zero of the dielectric constant and, in the absence of

damping, becomes infinite. Power series are developed for

the case of a single null point. With a double null point the

singular points can be represented by known functions. The

singular points so determined give rise to higher harmonics

which are not radiated by the transmitter. --C. E. P. B.

A-428 Forsyth, P. A. ; Currie, B. W. and Vawter, F. E. , Scattering of

56 Mc/s radio waves from the lower ionosphere. Nature, London, 171(4347) :352-353, Feb. 21, 1953. ref. DWB--A persistent scatter echo was recorded at Saskatoon (52. 1 N, 106.6 W).

It was strongest in March and in the morning hours. Estimated

height of scattering region 85 km. --C. E. P. B.

A-429 Franklin Institute. Laboratories for Research and Development, Phila., Development, design, instrumentation. Blos - som 4 series . Contract AF 19(122) -33, Final Report F-2106,

March 1, 1950. 2 V. (401 p.) numerous figs, (some fold.,

also many photos, some in color), refs. (vol. 2, p. 306-308),

bibliog. (Vol 2, p. 401. ) DWB--The details of history, organization, design, development, instrumentation and launching

of the V-2 rockets at White Sands (Blossom I, II-A, II-B and

III and Aspect I, II, and III from Feb. 29, 1947 to June 11, 1949

in Missiles No. 20, 28, 37 and 39) are treated in Vol. 1, along with complete information about the development of the

V-2 and other rockets in Germany from 1932-1942. The second

volume deals with the design, development and instrumentation of the Blossom IVseries. Blossom IV -A was carried by

V-2 rocket No. 41 fired on March 21, 1949. Radiation, electrical pressure, temperature, ionospheric and other data were

obtained by parachute, radar, radio and optical methods. Blossom IV-B was fired June 14, 1949. --M. R.

A-430 Friedman, Bernard and Russek, Joy (N. Y. Univ. Wash. Square

Coll. ), Addition theorems for spherical waves . N. Y. University. Washington Square College of Arts and Science. Mathematics Research Group, Contract AF 19(122) -42, Research Report, No. EM-44, June 1952. 19 p. 10 refs. , 39 eqs. DWB--
129

Expansions or "addition theorems" for the spherical wave functions:

J (KR)P (m) (Cos 0) e im d hn(1) n n r

(KR)P (m) (Cos 0) e im and h (2) (KR) (m) (Cos 0)

TM^'

n n

With reference to the origin 0, have been obtained in terms of

spherical wave functions with reference to the origin 0; where

has the coordinates (h , O

) with respect to 0. Using

the above mentioned addition theorems, we have obtained an

expansion for . , e

* * r 12

r 12 a wave which is spherically symmetric about the source Q,

where Q is referred to the origin 0, in terms of products of

spherical waves with respect to origin and spherical waves

with respect to 0'. --Authors' abstract.

A-431 Friedman, Herbert, Rocket observations of the ionosphere.

Institute of Radio Engineers, Proceedings, 47(2):272-280, Feb.

1959. 9 figs. , 2 tables, 26 refs. , 2 eqs. DLC. Correction

in Ibid, 47(4): 567, April 1959, Eq. no. 2 on p. 275 should

Np + -*-N0 + N. --Daytime electron density profiles

measured at Fort Churchill have been found to be similar to

those observed at White Sands. One winter nighttime flight

showed very little ionization, less than 20, 000 electrons per

cc up to 165 km. Polar blackout produced strong enhancement

of the D-region electron density down to 55 km. NO+ is the

predominant ion below 200 km during the night, but + becomes

the most abundant ion above 150 km during the day. Solar

flares are accompanied by X-ray bursts capable of penetrating

to the 60 km level and sufficiently intense to account for sudden ionospheric disturbances. At night a diffuse glow of Lyman -06 is visible over the entire sky. From the observed intensity it is possible to estimate the electron density of interplanetary space. --Author's summary.

A-432 Fuchs, J. , Eine Radio Methode zur Bestimmung de Absolut- tentemperatur der Ionosphare. (A radio method for determination of the absolute temperature of the ionosphere. ) Meteorologische Zeitschrift, 53(2):41-44, Feb. 1936. tables, 10 refs. , 13 eqs. DLC--The method is used here to show that the Fregion temperature of 400 - 1, 000 C near the equator largely

depends on the electron density indicating that the temperature aloft is controlled by the absorbed UV-energy in the ionization process. --W. K.
130

A-433 Fulton, B. ; Sandoz, O. and Warren, E. (all, Defence Res.

Telecommunications Estab. , Ottawa, Canada), The lower

frequency limits for F-layer radio propagation. Journal of Geophysical Research, Wash., D.C., 65(1): 177-183, Jan. 1960.

12 figs. , 4 refs. , 13 eqs. DWB, DLC--The band of frequencies propagated via the ionosphere by the high-angle ray and

that propagated by the low-angle ray are both limited at their

low-frequency ends by reflections that occur at lower ionospheric heights. Methods are developed in this paper for the

calculation of these limits. --Authors' abstract.

A-434 Furutsu, K. , One communication in the sea by VLF electromagnetic waves. Japan. Radio Research Laboratory, Journal,

5(19):19-33, Jan. 1958. 15 figs. , ref.

A-435 Gallagher, P. B. , Analysis of a new type of radio scattering

from the ionospheric E-reqion. Stanford University, Electronics Laboratories, Contract N6 onr 251(07), Technical Report

No. 107, May 7, 1956.

A-436 Gallagher, P. B. and Villard, O. G. , Jr. , Radio reflections

from artificially produced electron clouds: Smokepuff II . Stanford University, Electronics Laboratories, Contract AF 19(604)-

2075, Scientific Report No. 1, Dec. 1958.

A-437 Gallet, R. M. and Helliwell, R.A. , Origin of "Very-low-frequency emissions". U. S. National Bureau of Standards, Journal of Research, 63D(l):21-27, July-Aug. 1959. 4 figs. , 2 tables, 14 refs.

A-438 Gallet, R. , Une nouvelle station ionospherique a Dakar. (A

new ionospheric station at Dakar. ) Annales de G4ophysique,

5(3):248-249, July-Sept. 1949. 3 refs. , eq. MH-BH--The author discusses the value of this station for studying the following ionospheric phenomena; the effect of longitude upon the

ionization of the F2 layer, the characteristics of the sporadic

E layer at equatorial latitudes, precise measurement of the

critical frequency of the normal E layer, absorption in the D

layer and "fade out. " The geographic and geomagnetic coordinates of the station are given. --I. L. D.

A-439 Gallet, Roger, Sur la nature de la couche E sporadique et la

turbulence de la haute atmosphere. (On the nature of the sporadic E layer and the turbulence of the upper atmosphere.

)

Academie des Sciences, Paris, Comptes Rendus, 233(25) :1649-

1650, Dec. 19, 1951. ref. , eq. DWB-An attempt to formulate

the relation between the optical turbidity, the changes in molecular density (turbulence) and the electronic density in the high

atmosphere as a method of explaining and measuring the fluctuations in the ionospheric E layer. --M. R.
131

A-440 Gallet, R.M. (Nat. Bur. Standards, Boulder, Colo.), Aerodynamical mechanisms producing electronic density fluctuations in turbulent ionized layers . Institute of Radio Engineers,

N.Y. , Proceedings, 43(10): 1240-1252, Oct. 1955. 8 figs. , table, 7 foot-refs. , bibliog. p. 1252, numerous eqs. DLC --Various radio effects of the turbulence in the low ionosphere are discussed with a view toward determining the order of magnitude of the turbulence parameters in this region. These effects include vhf scattering, sporadic E layer phenomena, and

diffraction patterns in reflection. The required electron density fluctuations (aN lKr fluctuate around 10

_i* and the scale

of the turbulence is roughly 100 to 200 m. The latter quantity measured directly in the troposphere is of about the same

order of magnitude. The underlying purpose of the paper is to

study the aerodynamical mechanisms of turbulence. Pressure

fluctuations result from the "collisions and extensions between

turbulent eddies" in a uniform gas, or from vertical transport in

the atmosphere with its varying pressure. It is shown that

such pressure fluctuations are soo small, by a factor of about

10"4

f to produce the observed density fluctuations. However,

the vertical transport mechanism produces two other effects

which are independent of the energy of the turbulence and are

of the right order of intensity. First, in a nonadiabatic atmosphere the vertical transport of air masses produces fluctuations

of temperature. These, in turn, give rise to air density fluctuations, and proportional electron density fluctuations. Second, fluctuations of electron density result directly from transport in the presence of a gradient of electron density. These

two effects, for the same uniform turbulence, occur at different levels in an ionospheric layer. They are sufficient to ex- plain the stratification properties of sporadic E. An expression for the scale of turbulence is obtained from the gradients

of winds circulating in the low ionosphere. Hence, the properties of sporadic E phenomena should be interpreted in terms

of meteorological factors (winds, synoptic masses of air,

fronts, etc. ). It is pointed out that the same transport mechanisms are acting in the troposphere, the gradients of water

vapor content playing the role of the gradients of electron density. --Author's abstract.

A-441 Gallet, Roger M. (Nat. Bur. of Stands. , Boulder, Colo.),

The spectrum of the electron density fluctuations in the ionosphere. (In: Polar Atmosphere Symposium, Oslo, July 2-8,

1956, Proceedings, Pt. 2, Ionospheric Section. N. Y. , Pergamon Press, 1958. p. 165-170, fig., 4 refs. , 18 eqs. ) Also

issued in Journal of Atmospheric and Terrestrial Physics, London, Special Supplement, Pt. 1, 1957, pub. 1958. p. 165-170.

DWB, DLC--
132

A theory of atmospheric temperature and density fluctuations

and of their effect upon ionospheric electron density is developed and the application of this theory to the scattering of

radio waves is discussed. --G. T.

A-442 Gallet, R.M. and Helliwell, R. A. , Origin of "Very-Low-Fre - quency Emissions". U. S. National Bureau of Standards, Journal of Research, Sec. D, 63(l):21-27, July/Aug. 1959. 4 figs.

,

2 tables, 14 refs. , 9 eqs. DLC, DWB--Selective travelingwave amplification in the outer ionosphere is postulated to

explain very-low-frequency emissions, a class of very lowfrequency (1 to 30 kilocycles per second) natural noise. By

analogy with the mechanism of traveling wave tubes, low-level ambient noise in the outer ionosphere is amplified in streams

of incoming ionized solar particles at frequencies for which

the stream and wave velocities are equal. Required velocities

are in the range 0. 01 to 0. 1 c (where c is the velocity of light).

Streams with densities of the order of one electron per cubic

centimeter would provide sufficient energy. Phenomena which

can be explained qualitatively by the theory are the hiss, quasiconstant tones, dawn chorus and related transients, and very

long trains of whistler echoes. A quantitative example shows

how the theory can reproduce the general form of certain characteristic discrete spectra "hooks" of emissions, and how this

leads to definite values of particle velocity and a law for the

distribution of electron density in the outer ionosphere. -- Authors' abstract.

A-443 Gardner, F. F. , The use of atmospherics to study the propaga- tion of very long waves. Philosophical Magazine, London,

41(323): 1259-1269, Dec. 1950. 6 figs. , 4 refs. DLC--The

'level" of integrated atmospherics received on narrow-band re- ceivers tuned to a series of different frequencies between 3. 5

and 50 kc/s has been recorded and the results analyzed. The

most significant effect is a marked attenuation of waves of

frequency below 10 kc/s when travelling over distances of

1, 000 km or more. This attenuation is discussed and is re- lated to the quasi-sinusoidal waveform often assumed by atmospherics which have travelled great distances. A decrease

in the level of atmospherics has been found to occur during

sudden ionosphere disturbances on frequencies below about

10 kc/s. This contrasts with the known increase on frequencies above about 20 kc/s. --From author's abstract.

A-444 Gardner, F. F. and Paws ey, J.L. , Study of the ionospheric Dreqion using partial reflections . Journal of Atmospheric and

Terrestrial Physics, 3(6):321-344, July 1953. 18 figs. , 2 tables, 9 refs. , 6 eqs. MH-BH--
133

A method is described of regularly observing echoes at vertical incidence down to 60 km, using high sensitivity on 2

Mc/s at a low-noise site near Sydney, Australia, and of determining electron density and collision frequency from them.

It is found that the ionosphere below the normal E region includes a region at about 70 km with maximum ionization at

midday, disappearing at night, and one at 90 km extending

up to normal E region and, by day, descending to merge with

lower region. This is the main cause of medium and short

wave attenuation. --C. E. P. B.

A-445 Gardner, F. F. , Ionospheric thermal radiation at radio frequencies. II. : Further observations. Journal of Atmospheric

and Terrestrial Physics, 5(5/6): 298-315, 1954. -Observed ionospheric noise at 2 Mc/s at a quiet location in Australia.

Found midday temperature of 200 to 250 K. During SID's the

temperature went up 40 K, probably due to a change in height of the absorbing region. By comparing and X noise, it was shown that the temperature decreased with height. Explains results in terms of a fixed temperature -height model

similar to that determined from rocket measurements, but

having a minimum of 217 K at 80 km. Used a single horizontal dipole antenna 80 feet high and 235 feet long. Measured aerial temperature by comparison with a dummy antenna.

-L.A.M.

A-446 Gardner, F. F. , The effect of sudden ionospheric disturbances

(SID) on 2. 28 Mc/s pulse reflections from the lower ionosphere. Australian Journal of Physics, 12(l):42-53, March 1959.

7 figs. , 2 plates, 10 refs. . A-447 Garriott, O. K. , A note on whistler propagation in regions of

very low electron density. Journal of Geophysical Research,

63(4): 862 -865, Dec. 1958. 4 figs.

A-448 Gates, D. M. , Preliminary results of the National Bureau of

Standards radio and ionospheric observations during the Inter- national Geophysical Year. U.S. National Bureau of Standards,

Journal of Research, 63D, No. 1:1-14, July-Aug. 1959. 10 figs.

2 tables, 18 refs.

A-449 Gautier, T.N., Jr. and Sargent, C. J. , Prediction of the likelihood of interference at frequencies of 30 to 42 megacycles

in Alaska. U. S. National Bureau of Standards, Journal of

Research, 52(1):21-31, Jan. 1954. Research Paper, No. 2468.

50 figs. , 3 refs. DLC--The likelihood of interference with

very-high-frequency networks in Alaska from stations operating on similar frequencies in other parts of the world, as a function of season, sunspot number, and time of day, is
134

presented. This example serves as a model for similar computations for other communication links. Calculations are based upon regular reflection from the F2 layer, and data are supplied for estimating the probability of interference from

sporadic E reflections. --Authors' abstract.

A-450 Gerson, Nathaniel C. , Large-scale sporadic movements of

the E-layer of the ionosphere. Nature, London, 166(4216) :316-

317, Aug. 19, 1950. fig. DWB--Preliminary results given of

work on sporadic movements of E-layer, undertaken by radio

amateurs (operating on 50 Mc/s) situated in various parts of

North America. Observed direction of movements and speeds

of 4 reflecting regions suggest an anticyclonic circulation.

--G.J.E.

A-451 Gerson, N.C., Noise levels in the American Sub-Arctic.

Institute of Radio Engineers, Proceedings, 38(8): 905-916,

Aug. 1950. 15 figs. , table, 6 refs. DLC --Detailed results

of a six months study of the atmospheric static intensity at

150 Kc in northern and southern Canada are discussed. The

noise equipment comprised an 18-tube superheterdyne receiver

(Kammarlund Super Pro, Type BC-779-A along with an automatic recorder (Esterline Angus). --W. N.

A-452 Gerson, N.C., Summary of a meeting on mathematical problems in ionospheric research. U. S. Air Force, Cambridge

Research Center, Geophysical Research Papers, No. 7; 175-

176, Dec. 1950. DWB--Short discussion on a number of problems, mainly in the fields of the propagation of short and long

radio waves, the magnetoionic theory, and tropospheric influences and the solar ionosphere. --A. A.

A-453 Gerson, N.C., Continental sporadic E activity. American

Geophysical Union, Transactions, 32(l):26-30, Feb. 1951. 8

figs. , 2 refs. MH-BH--Numerous reports of abnormal radio

propagation, due to reflections from a sporadic E layer, were

received from ham radio operators all over the United States

and are plotted on hourly charts for the period 2300 GMT, June

17 to 0500, June 18, 1949. Movements of the centers of mass

of the Es layer are also shown on a composite map. One layer

was in the southeast (moving west), one in the Montana area

(moving south) and one in the Nevada area (moving west). -- M.R.

A-454 Gerson, N. C. , Abnormal E region ionization. Canadian

Journal of Physics, 29(3):251-261, May 1951. 10 figs. , 12 refs.

DWB--The occurrence and sweep of sporadic E over North America was studied with the cooperation of radio amateurs transmitting in the frequency range 50-54 mc/sec. The movement
135

and geographical extent of the reflection areas were determined by oblique incidence radio observations. The behaviors of two sporadic E centers observed on June 13, 1949 are described. --I. L.D.

A-455 Gerson, Nathaniel C. (Air Force Cambridge Res. Labs. , Mass. ), Sporadic E investigations . International Council

of Scientific Unions, Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 121-125. fig. , 3 refs. DWB--Methods of exploring the ionosphere with radio

(vertical incidence back scatter, and by networks of amateur

stations) are reviewed, and the program initiated by the U. S.

Air Force for collection of sporadic E layer data by the last

named method described. Charts of sporadic E layer reflection points for 0100Z and 0500Z May 20, 1949, when 426 radio

contacts were reported show a "cloud" moving from Arkansas

toward the NNW at average velocity of 125 km/h. --M. R.

A-456 Gerson, N. C. , Bewequnqen der abnormalen E-Schicht der

Ionosphare. (Movements of the abnormal E layer of the ionosphere. ) Zeitschrift fur angewandte Physik, 4(3):81-82, March

1952. 3 figs. DLC -Observations of Es "clouds" (with the help

of radio amateurs) at about 110 km in U. S. June 16-17, 1949, are plotted. One in the northeast moved from ENE at 130 km/h.

A smaller one in 100 W moved from SSE, 300 km/hr, and a

third near 40°N, 115°W moved from E at 100 km/hr. The sudden appearance and disappearance of the clouds is attributed

to vertical movements. --C. E. P. B.

A-457 Gerson, N.C. (Geophysical Res. Dir. , Cambr. , Mass.),

A note on the conference on ionospheric physics. U. S. Air

Force. Cambridge Research Center, Geophysics Research

Papers, Ho. 11:13-14, 1952. DWB--The author, in his introductory remarks to the conference reports, brings out the fact that

physicists have neglected many important fields of research

such as were represented in this conference (physics of the

high atmosphere and study of planetary atmosphere) while concentrating on nuclear and cosmic ray research. The atmosphere is considered as comprising several shells; the ionosphere (80-400 km), the mesosphere (400-1000 km) and the exosphere (above 1000 km). Specific problems which are being

solved are: dissociation and recombination processes, corre- lation of solar and ionospheric phenomena, improvement of

spectroscopic methods and microwave observational techniques. --M. R.
136

A-458 Gerson, N. C. f Sporadic E propagation. Journal of Atmospheric and Terrestrial Physics, 6(2/3): 113-116, March 1955. fig.

DWB--Observations in N. America mostly in summer of long

range communication on 50 Mc/s due to Es reflection showed

most frequent station separation around 1500 km. Results are analyzed into single hop, double hop (one cloud, peak about

1300 km) and a few double hop (2 clouds). Es cloud diameter

is 600-1250 km (mean 925 km) E - W, probably more N - S.

Possibility of 50 Mc/s communication up to 7000 km is discussed. --C. E. P. B.

A-459 Gerson, N. C. (AVCO Manufact. Corp., Boston, Mass.),

Latitude effects in sporadic E observations . AGARDOgraph,

Paris, No. 34:81-96, Sept. 1958. 11 figs. DWB (629. 1323

N864a) --During the period 1949-1951, North American radio

amateurs participated in a cooperative study of abnormal propagation conditions in the VHF band. About 350 amateurs

were involved, mainly from the United States and Canada,

but also from Mexico and Central America. The study was

made at a radio frequency of 50 Mc/s with some observations

also obtained at 144 Mc/s. Reports were prepared by the amateurs whenever they contacted or received another transmitter

operating in this frequency range, because of unusual propagation effects. The reports provided such factors as the terminal points of the propagation path, the time, signal strength,

character of the signal, and so on. Several conclusions have

been drawn regarding the geographical distribution of sporadic

E but, to determine the long-term Es climatology, additional

observations over many years are necessary. --Author's abstract.

A-460 Gerson, N. C. (Trapels Road, South Lincoln, Mass.), Annual

distribution of sporadic E. Journal of Atmospheric and Terrestrial Physics, N.Y. , 16(1/2): 189-191, Oct. 1959. 2 figs. , DW$

DLC--This study is based on some 19, 000 VHF contact reports

during 1949 over North America. The Es cloud location from

each contact was determined and summarized into number of

hours of occurrence of reflections within a degree square (area

bounded by 1 lat. and 1 long) and mapped in isopleths. A diagram featuring monthly distribution of sporadic E shows it is

almost entirely a summer phenomenon in the northern hemisphere. --W. N.

A-461 Gerson, N.C., Very long distance ionospheric propagation.

Journal of Atmospheric and Terrestrial Physics, 13(1/2): 169-1 72,

Dec. , 1958. 2 figs. , table, 26 refs.
137

A-462 Gherzi, Ernest, Ionospheric reflections and weather forecast- ing for Eastern China. American Meteorological Society, Bulletin, 27(3): 114-116, March 1946. 4 refs. MH-BH--Investigations at the Zi-Ka-Wei Observatory (Shanghai) during the last

5 years show: (1) with dominant Pacific trade wind air mass:

E layer reflection, (2) with Siberian air mass: F layer reflection and (3) with tropical air mass, in most cases: F2 layer

reflection.

A-463 Gherzi, Ernest (Macao Met. Ser. ), A ionosfera eo tempo.

(Ionosphere and weather. ) Aquaceiros em Macau durante a Moncao de sudoeste. (Showers at Macao during the south

western monsoon. ) Macao. Servico Meteorologico, Notas

Cientificas, Nos. 3 and 4, 1952. 2 pieces. In English and

Portuguese. DWB--In contrast to a number of bad forecasts

made in 1949-51 by Far East weather services, the author maintains that his method (first used in 1939) of predicting weather

from the height of the ionospheric layer which reflects pulses

(6 Mc) would have given correct forecasts every time. If the

reflecting layer is at 230-280 km then Siberian (polar continental) air is expected for 12 hours, and if it is an F layer at

^ 300 km, then a tropical air mass is expected. If a typhoon is about 400 km from Macao it will not reach station if echo is from 230-280 km, but will from 300 km region. -- M R.

A-464 Ghosh, Mrinmayee, Determination of the F-reqion collisional

frequency over Calcutta. Journal of Atmospheric and Terrestrial Physics, London, 8(1/2):116-118, Feb. 1956. 2 figs. , 2

refs. DWB--The diurnal variation of the collisional frequency

of the F region, calculated from the absorption of a radio wave

passing through it, varies from 102/sec at midnight to 5 X 10^

/sec near noon. The rate of rise increases with cos X, which

is explained by a rapid rise of temperature in the F region with

the approach of noon. --C. E. P. B.

A-465 Ghosh, S.N., (Harvard Univ. ), Methods for the measurement

of upper atmospheric characteristics. Journal of Scientific and

Industrial Research, Sec. A, New Delhi, 14(6): 277-284, June

1955. 6 figs. , 12 refs. , 2 eqs. DWB--A review of technical

methods, both direct and indirect, for sounding the upper atmosphere. Indirect methods include radio echoes for probing

ionosphere, acoustical sounding, searchlight methods for determining density, meteor and auroral observations and spectroscopic studies of dissociation and recombination. Direct

methods include airglow, rocket and balloon measurements

and direct determination of temperature, winds and ionization

in the ionosphere. Laboratory and theoretical studies of microwave propagation and photochemistry are also outlined and

illustrated. --M. R.
138

A-466 Ghosh, S. P. , Long distance radio communication. Application of records kept at ionospheric observatories. Science

and Culture, Calcutta, 6:199-204, 1940. 6 figs. , table. DLC

--First is the role of the ionosphere considered, then the characteristics for both vertical and oblique propagation, and finally, some frequency problems are discussed. Plottings of

MUF data per se and vs. local time is shown and how to obtain optimum frequencies over a given distance are graphically presented. --W. N.

A-467 Gibbons, J.J. and Nertney, R. J. , A method of obtaining the

wave solutions of ionospheric ally reflected long waves, including all variables and their height variation. Journal of

Geophysical Research, 56(3):355-371, Sept. 1951. 8 figs.

,

table, 3 refs. , 25 eqs. MH-BH—Solution of one-dimensional

wave equation with application of wave theory to study of

wave propagation in the ionosphere. Reflection coefficients

are presented graphically for several distributions of electron

density and results compared with experiment. Solution presented here is compared with W. K. B. method. The author's

method gives heights far too low for E layer, but phase heights are consistent with experimental data. --M. R.

A-468 Gibbons, J.J. and Nertney, R.J. (Penna. St. Col., Ionospheric Res. Lab. ), Wave solutions, including coupling, of ion- ospherically reflected long radio waves for a particular E re- gion model. Journal of Geophysical Research, 57(3): 323-338,

Sept. 1952. 9 figs., table, 10 refs. , 10 eqs. DWB--This paper

extends previous work to the solution of coupled wave equations arising in ionospheric wave propagation to diurnal and

seasonal models of E-region above Pennsylvania, in which a Chapman E-region has maximum electron density at constant

height. A wave traversing a coupling region below the "reflection" level excites a new wave propagated in the same direction and a reverse back-scattered wave, which appears as a reflected wave. In 150 kc/sec waves these effects occur near

N = 300 e/cm3. At night the increase in height of the bottom

of the layer increases the effect and causes stronger split

echoes and greater polarization, but the experimental results

require also a D-layer. --C. E. P. B.

A-469 Gibbons, J. J. and Bellas, F. E. , Pt. I. A method of treating

the plane wave equation. Pt. II. The coupling problem at 150

Kc/sec. Pennsylvania. State College, Ionosphere Research

Laboratory, Contract AF 19(122) -44, Scientific Report, No. 42,

Oct. 15, 1952. 22 p. 2 figs. , 5 refs. , 16 eqs. DWB--This re- port is concerned with two separate topics: (I) a method of attacking the wave equation in an inhomogenous medium and (2) a method of reducing the coupling between ionospheric modes.
139

so as to treat the coupling problem as one of regular reflection

due to a variation in refractive index. It was first thought that

the method of (1) would be applied to the coupling problem (2),

but actual calculation showed this to be pointless; the solutions were so closely W. K.B. that the problem would be no

test of any practical computation method. Moreover, some

questions of boundary conditions in problem (1) are not yet settled; we prefer to consider that part of the report as a preliminary investigation. --Authors' abstract.

A-470 Gibbons, J. J. , Schrag, R.L. and Waynyck, A. J. , Long delay

ionospheric echoes at 150 kc/s . Nature, London, 171(4349):

444-445, March 7, 1953. fig. , 7 refs. DWB--Authors find

virtually total reflection from a virtual height of 940 km. Records for Nov. 10, 1952, shown. Possible causes are discussed. --C. E. P. B.

A-471 Gibbons, J. J. and Rao, B. R. , Calculation of group indices

and group heights at low freguencies . Pennsylvania State

Univ. Ionosphere Research Laboratory, Contract AF 19(604)-

1304, Scientific Report No. 92, April 1, 1957. 35 p. 7 figs.,

3 tables, 7 refs. , 59 eqs. DWB--In this report is given a method of obtaining a set of curves from which the group height to be expected from a given electron density profile at a given frequency can be quickly determined. Such curves are presented for 75 kc/sec, 150 kc/sec, and 500 kc/sec. A

formula is derived from which the group index u' is easily

computed as a function of u and x. --Authors' abstract.

A-472 Gibbons, J. J. and Waynick, A. H. , The normal D region of

the ionosphere. Institute of Radio Engineers, Proceedings,

47(2):160-161, Feb. 1959. 10 refs. , eqs. DLC--The general

theory of low frequency sounding in the lower ionosphere is

discussed in order to indicate the radio transmission characteristics which a D -layer model must satisfy. D layers based

on the fundamental physical processes from 60 to 90 km,

which have been presented up to now, have not been completely satisfactory. There is indication that the more ac- curately determined values of fundamental parameters now

available, such as reaction rates, will lead to a more satisfactory model. --Authors' summary.

A-473 Ginzburg, V. L. , O vliianii mezhduelektronnykh soudarenii

na pogloshchenie radiovoln v F-sloe i v solnechnoi korone.

(The influence of collision among electrons on absorption of

radiowaves in F layer and in the solar corona. ) Zhurnal Tekhnicheskoi Fiziki, Moscow, 21(8): 943-947, Aug. 1951. 10 refs.,

9 eqs. DLC--
140

Using the previous results obtained by himself and other authors, the author derives a formula for the calculation of the frequency of the impacts between electrons and molecules. The

use of this formula, however, requires the knowledge of the

temperature of the ionized layer, or other corresponding data,

which must be obtained independently of the measurement of

the absorption of the radio waves. In principle, as the author

shows, the measurements of this absorption might be sufficient to determine the frequency of electron-electron impacts,

but this could hardly be applied in actual practice, because

the electron-electron impacts would have but very little influence upon the absorption in comparison with the electron-molecule impacts, unless the wavelength is very much larger than

200 m, and this does not seem to be of practical interest. The

author suggests, however, that means for the measurements

necessary for the calculation of the frequency of electronmolecule impacts in the ionized layers could be devised. -- Physics Abstracts, No. 338, 1953.

A.474 Gnanalingam, S. , An apparatus for the detection of weak

ionospheric echoes. Institution of Electrical Engineers, London, Proceedings, Pt. Ill, 101(72) :243-248, July 1954. 6 figs.,

7 refs. , 12 eqs. DWB--Transmitting frequency follows a cycle,

increasing linearly for a time and then returning rapidly to the

original value. A point some distance away receives each

signal twice, by ground path and ionosphere reflection, the

resulting interference giving an oscillation with beats at

which there are wave discontinuities. The beat frequency

can be detected with a narrow band filter. Wiring diagram,

detailed theory, determination of echo height and calibration

are described. With a transmitted power of 250 watts and

output band width of 1 c/s, echoes could be detected with a reflection coefficient of 3 X 10"°. Height determination is

accurate to 1. 4 km. --C. E. P. B.

A-475 Goldstein, L. ; Anderson, J.M. and Clark, G.L. (Univ. of

Illinois, Urbana. ), Interaction of microwaves propagated

through a gaseous discharge plasma. Physical Review, 90(1):

151-152, April 1, 1953. 2 figs. , 8 refs. DWB--Experimental

test of the extended theory of ionospheric cross modulation

proved that a transmitted wave can be increased and/or decreased in attenuation as a result of interacting of a disturbing pulse. A predicted modulated wave was produced in helium at 12 mm Hg and in argon at 2. 7 mm Hg. --W. N.

A-476 Golitsyn, G. S. (Academy of Sciences, Moscow), On the influence of the magnetic field on the character of turbulence in

the ionosphere. Journal of Geophysical Research, Wash. ,D. G

64(12) :2212-2214, Dec. 1959. table, 4 refs. , 11 eqs. DLC-
141

The influence of the earth's magnetic field on the character of

turbulence in the ionosphere is considered on the basis of the

equations of magnetohydrodynamics. The estimates given

show that its influence in the lower ionosphere up to heights

of 150 to 200 km can be neglected. At heights greater than

200 km the influence of the earth's magnetic field must be

considered in the dynamics of the medium. The fact that the

gases are highly rarefied constitutes an additional problem in

formulating a theory of turbulence for the upper regions of the

ionosphere. It is shown here that the ratio of Kolmogoroff 's inner scale of turbulence to the mean free path of neutral molecules decreases with the decrease in number of particles n

and n

/4 reaching the value of the order 30 or less at the height

of 250 km. Therefore, the theory of turbulent motions at such

heights should not entirely neglect the molecular structure of

the medium. --Author's abstract.

A-4'77 Goodwin, G.L. (Physics Dept. Adelaide Univ. Australia),

The movements of sporadic E layer clouds. Journal of Atmospheric and Terrestrial Physics, London, 11(3/4): 177-186, 1957.

3 figs. , table, 10 refs. , 5 eqs. DLC--An account is given of

some measurements of the magnitude of the drift velocity of

isolated sporadic E clouds, using a C. W. technique. The

method involves determining the rate of change of phase path

of a wave reflected at almost vertical incidence, by measuring

the rate of fading of the received signal due to interference between the reflected and ground waves. A method using two

spaced loop-aerials is suggested for determining the direction

of drift. Some experimental evidence is described indicating

that the angular spread of scatter from Es clouds is larger at

night than during the day. --Author's abstract.

A-478 Goodwin, G.L. (Dept. of Physics,. Adelaide Univ. ), A discussion of ionospheric demodulation near gyro frequency.

Australian Journal of Physics, Melbourne, 12(2):157-163, June

1959. 4 figs. , 15 refs. , 3 eqs. DLC--Observations made in

Adelaide of the ionospheric demodulation of radio waves near

gyro frequency at vertical incidence are discussed. The effect occurs in the region of about 90 km, and does not appear

to decrease through dawn. An F layer reflected wave is demodulated by unequal amounts during its two passages through

the region. The large magnitude of the effect and its lack of

dependence on modulation frequency seem to be inconsistent

with the theory of wave interaction. --Author's abstract.
142

A-479 Goody, R. M. (St. John's College, Cambridge), The physics

of the stratosphere. Cambridge, Eng. , University Press, 1954.

137 p. 60 figs. , 17 tables, bibliog. p. 176-181, eqs. Price:

$5.00. Cambridge Monographs on Physics. DLC--A simple

but up-to-date and accurate treatment of the structure, composition and energy conditions in the upper atmosphere, with

emphasis on experimental rather than theoretical results. The

latest equipment, including rockets, is considered. The layer

between that wherein "weather" plays an important role, and

the ionosphere (e. g. , from 12 to 80 km) is emphasized. The

several chapters take up the following subjects: 1) Discovery

and nomenclature of stratosphere; 2) Temperature and its measurement by sound propagation, meteor and rocket techniques;

3) Composition (H^O, C0~, rare gases, etc.); 4) Ozone; 5)

Winds and turbulence in tne stratosphere; 6) Radiation. The

last chapter is especially complete and up-to-date, taking up

the latest theoretical and experimental knowledge of the radiation balance in the stratosphere, the effects of various gases

(H^O, COp, NO and 2

) on the absorption of solar and terrestrial radiation, line shapes, spectroscopy and, finally, the

effect of radiation balance on tropopause temperatures and

vice versa. --M. R.

A-480 Goroshankina, A. A. , K voprosu o lokalizatsii neodnorodnos - tei v ionosfere. (Localization of heterogeneity in the ionosphere. ) Akademiia Nauk SSSR, Doklady, 93(3):45S-461, Nov.

21, 1953. 2 figs. , 6 refs. DLC--Inhomogeneities, which

cause oscillations of signal amplitudes reflected from the F

layer can be located, according to the author, by means of

ionospheric soundings at different points at different frequencies simultaneously. Preliminary results of 14 observations

carried out by the author are presented and discussed. -- A.M. P.

A-481 Goudet, G. , Radiation and propagation of electromagnetic

waves of short wavelength. Annales des Telecommunication,

3:74-84, 113-125, 155-179, 182-208, 233-256, March-July, 1948.

--A survey of recent work both theoretical and experimental on

cm and dm waves, with a bibliography of 137 important papers

mentioned in the text. Part 1 discusses electromagnetic radiation theory and cm-wave equipment. Part 2 discusses reflection, refraction, diffraction, properties of the ionosphere, and

the effect of meteorological conditions. Radar receives special attention.
143

A-482 Grace, Clinton H. ; Kelso, J. M. and Miller, J. W. , The ex- perimental determination of the scale height, height of the

bottom and true height of the maximum ionization of the Elayer under undisturbed conditions . Pennsylvania. State College. Radio Propagation Laboratory, Contract AF( 122) -44,

Technical Report, No. 3, June 15, 1949. 15 p. 28 figs. , 7

tables, 8 refs. , 10 eqs. DWB--Since published data pertinent

to the subject can be classified into (1) undisturbed and (2)

disturbed categories, authors determined and developed the

respective parameters and present the detailed data obtained

for the normal conditions of the E layer which are discussed

in relation to the data for abnormal or disturbed conditions.

--W.N.

A-483 Grace, Clinton H. and Underhill, C. R. (Penna. St. Coll.,

Radio Propag. Lab.), Measurements of sporadic E ionization

at State College. Pennsylvania. Pennsylvania. State College.

Radio Propagation Laboratory, Contract AF 19(122) -44, Basic

Ionospheric Research, Technical Report, No. 14, June 30,

1950. 18 + p. 7 figs. , tables. DWB--The detailed data on

sporadic E layer for the year 1949 are presented. Sporadic E

layer is more prevalent in summer than in winter. However

the highest frequency at vertical incidence, approximately 18

Mc, occurred on Nov. 1st. An example of the unpredictability

of the sporadic E layer is presented as well as details of the

stormy conditions of Nov. 2, 1949. --W. N.

A-484 Grace, Clinton H. (Penna. St. Col. Ionos. Res. Lab.), High- power manually-operated vertical incidence ionospheric height

measuring equipment. Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic Ionospheric Research, Technical Report, No. 22, June 25, 1951.

39 p. 17 figs. , 4 refs. DWB--Detailed description in text,

photos and block diagrams of the new and modified measuring

equipment used to determine the vertical incidence equivalent

height of ionosphere layers by the Breit-Tuve method. The

equipment is capable of operating continuously from 250 kc/s

to 5 Mc/s in several bands. Peak power output approaches

100 kw. --W.N.

A-485 Granalingam, S. and Weekes, K. , Weak echoes from the ion- osphere with radio waves of frequency 1.42 Mc/s. Nature,

London, 170(4316): 113-114, July 1952. ref. DWB--By a new technique, reflections were observed from 75-80, 90-95, and 112 km

in winter, and 102-105 km since mid-March. --C. E. P. B.

A*486 Grant, J. P. , More on the 'Plymouth effect". Wireless World,

64(12): 587-590, Dec. 1958. fig., table, 4 refs.
144

A-487 Great Britain. Dept. of Scientific and Industrial Research.

Radio Research Board, Fundamental principles of ionospheric

transmission produced by the Inter-Service Ionosphere Bureau

at the Great Baddow Research Laboratories of the Marconi

Wireless Telegraph Company Ltd. . Sept. 1943. Its Special Report, No. 17, 1948, reprinted 1952. 81 p. 69 figs. , eqs. DWB

--A thorough and systematic survey of knowledge of many as- pects of ionospheric transmission or reflection of electromagnetic waves. History, structure, physics, geometry, geography, ionization, polarization, formation of ionosphere,

diurnal and seasonal variation, reflection from multiple layers,

effect of frequency, corpuscular radiation, expansion, sunspot cycle, fading, magnetic storms, abnormal E, long distance scatter and spread F echoes. The name "Ionosphere" is

said to have been suggested by WATSON-WATT. -M. R.

A-438 Great Britain. Dept. of Scientific and Industrial Research.

Radio Research Board, Characteristics of the ionosphere observed in Great Britain 1930-1946: Measurements made at the

Radio Research Station, Slough, England, 1930-1946 and at

Burghead. Scotland. 1941-1946. Its Special Report No. 23,

1953. Vi + 16 p. 9 figs., tables, 21 refs. DLC, GB-MO--

The introduction gives a history of the methods of ionosphere

investigation — critical frequency, pulse method, etc. In

Pt. 2 the observations at Slough and Brughead, Scotland, are described. Appendixes define units and symbols and list the

hourly measurements. Microfilm or enlarged copies can be

bought.

A-489 Great Britain. Hydrographic Office, The Admiralty list of

radio signals. Vol. 4, Meteorological observation stations.

London, 1954. 263 p. printed on one side only. DWB-Complete list of some 12, 000 world meteorological stations ar- ranged by countries, with station no. , lat. , long. , and altitude (ft). -C.E. P. B.

A-490 Greenhow, J. S. and Neufeld, E. L. , Large scale irregularities

in high altitude winds . Physical Society of London, Proceedings, 75(2): 228. Feb. 1. 1960.

A-491 Gregory, J.B. (Canterbury Univ. College, Christchurch,

N.Z. ), Ionospheric reflections from heights below the E re- gion. Australian Journal of Physics, Melbourne, 9(3):324-342

Sept. 1956. 6 figs., 5 tables, 2 plates, 18 refs. DLC-The

pulse method of radio sounding has been used at 1. 75 Mc/s to

detect low ionospheric regions whose voltage reflection coefficient exceeds 4 X 10-6

. Observations from Feb. to July 1955

have revealed reflections, from 95 km vertical height and of
145

day-time occurrence only, which are believed to originate in

the lower E region. A region with a lower boundary predominantly at 85 km has been found to exist continuously, and

previous suggestions as to its meteor origin are aueried.

A series of complex partial reflections have been detected

during day-time only down to 53 km, with significant heights

near 75, 67, and 55 km. The occurrence and strength of thesa

lower reflections increases markedly during winter. From re- cords of high absorption conditions during winter days, a connection between the decrease in strength of E region reflections and the increase in strength of partial reflections between

63 and 88 km approximately is demonstrated. --Author's abstr.

A-492 Gregory, J. B. (Physics Dept. , Canterbury Univ. College,

Christchurch, N. Z. ), The relation of forward scattering of

very high frequency radio waves to partial reflection of med- ium frequency waves at vertical incidence. Journal of Geophysical Research, Wash., D.C., 62(3): 383-388, Sept. 1957. 5

figs. , 7 refs. DLC--A comparison is made between published

VHF forward-scatter data and results of vertical-incidence investigations of the lower ionosphere, mainly at a frequency of

1. 75 Mc/s. The received waves in each type of transmission

are shown to have many similar characteristics, such as temporal variations, and to originate in the same height regions.

It is concluded that the two types of transmission have a common origin. --Author's abstract.

A-493 Grenet, Gaston, La conductivite electrique de 1 'ionosphere

et les perturbations du champ magnetique terrestre de frequence musicale et plus basses. (Electric conductivity of the

ionosphere and geomagnetic field disturbances in the audible

and lower frequency ranges. ) Academie des Sciences, Paris,

Comptes Rendus, 242(3): 401 -403, Jan. 16, 1956. table, 2 refs.

Also: Benoit, Rene, Sur le bruit radio-electrique basse frequence du champ magnetique terrestre . (On the radioelectric

low frequency noise of the geomagnetic field.) Ibid., 242(21):

2534-2535, May 23, 1956. fig. DLC--The first paper contains

theoretical considerations (involving ionospheric critical frequencies, conductivities and layer thickness) from which it appears that low-frequency electromagnetic waves cannot pass

through the ionosphere and consequently the origin of geomagnetic field disturbances in the audible range must be other than

extraterrestrial. BENOIT reports measurements of low-frequency

noise, made by himself in Bani-Abbes (Algerian Sahara). During a ten-day period only isolated noises (due to sferics) registered at the rate of one per min. It is concluded that either

the time and place of measurement were exceptionally calm or low-frequency radio noise is entirely due to sferics, or both

assumptions are true, which would confirm GRENET's theory.

--G. T.
146

A-494 Griffiths, H. V. , Focusing of waves in radio reception. Nature,

London, 1 75(4465) :S48-949, May 28, 1955. 2 figs. DWB--

Describes occasional sudden increases for about 20 min from

1 to 20-30 mv/meter on 9700 kc/s transmission from Sofia re- ceived in S. E. England. --C. E. P. B.

A-495 Griffiths, H. V. , Long distance V. H. F. reception. Observations and an analysis of the causes of interference in band 1 . Wireless World, 65(4): 179-181, April 1959. 2 figs., 3 tables.

A-496 Gringauz, K. S. , Raketnye izmereniia elektronnoi kontsentratsii v ionosfere pri pomoshchi urtrakorotkovolnovogo dispersionnogo interferometra . (Rocket measurements of the electron concentration in the ionosphere by means of an ultrashort

wave dispersion interferometer. ) Iskusstvennye Sputnik Zemli, Moscow, No. 1:62-66, 1958. 4 figs. , 8 refs. , 4 eqs.

DLC. Translation issued in Soviet Physics, Doklady 3(3):6209,

1959. --The author presents the results of measurements of the

vertical distribution of electron concentration in the ionosphere from high altitude geophysical rockets released in the

U. S. S. R. during 1954-1958 - one rocket attained a height of

473 km. The determination of electronic concentration involved the use of a dispersion interferometer to measure the dispersion of radio waves emitted by a rocket. The rocket, which

was released at a small angle to the vertical, was equipped

with a transmitter emitting radio waves in the ultraviolet range

with a frequency of f \ and f2 = Pf 1- The radiowaves from the

rocket were received at two points on the earth and the phase

differences and level of oscillations received were recorded

continuously. The coordinates of the rocket were measured

simultaneously by optical radio methods and the ionosphere

was probed by means of a panoramic ionosphere station close

to the point of rocket release. The results of measurements

which are presented concern frequencies of f \ = 48 X 10° Hz

and f 2

= 144 X 106 Hz (p = 3). The coefficient of refraction

*? 1 was computed by the equation

T NLsJi

2«Tmf

(N - effective concentration of electrons, e and m - charge and

mass of electron, f - frequency Hz). The phase difference of

the two receivers referred to the higher freauency is given by

o

The variation of with variation of L from L to L + aL, taking into account *»? is given by
147

L + A L

* ^ = -#£7, (

P %~ ' ) / N <U

and the mean value of N over a L is given by

AL J „% £,2. - / . . a L

The rockets were released in middle latitudes. The results of

the measurements relative to the region lying below the maximum F ionization indicate that a clearly marked E layer does

not exist. The active height, at which radiowaves of the ionospheric station in the F layer are reflected lies 50-150 km

lower than the active heights recorded by the ionospheric station. --I. L. D.

A-497 Groenewold, H.J. (Royal Netherlands Met. Inst., DeBilt),

Triple splitting in a regular layer. International Council of

Scientific Unions. Mixed Commission on Ionosphere, Second

Meeting, Brussels, Sept. 1950. Proceedings, pub. 1951. p. 201-

205. 8 refs. , 8 eqs. DWB--Solution to equations to account

for observed types of triple splitting of the ionospheric layer

in mid-latitudes. Like reflection, it is explained as coupling

between elementary ray solutions. For vertical incidence

Bremmer's solution is presented in a more tractable form. -- From author's abstract.

A-498 Grosskopf, J. , Einige Bemerkungen zur Schwundanalyse im

M und DM-Bereich. (Some remarks to the fading analysis pertaining to the meter and decimeter regions.

)

Nachrichtentechnische Zeitschrift, 11(11) :577-586, Nov. 1958. lOfigs.,

9 refs. DLC.

A-499 Grosskopf, J. , Hohenabhangigkeit und Einfallswinkel bei

Streustrahlung im 100 MHz-Bereich. (Dependency of height

and angle of incidence of the scatter radiation in the 100 Mc/s

region.) Nachrichtentechnische Fachberichte, 12:99-102, 1958.

9 figs. DLC.

A-500 Grosskopf, J. , Die uberreichweiten extrem kurzer Wellen.

(The propagation range of ultra-short waves. ) Elektrische

Fernmeldewesen, Jahrbuch (Germany), Vol. 10:34-72, 1958.

32 figs. , 14 refs.

A-501 Gusev, V. D. ; Huang, Si-wen and Li, Jun, On the use of the

correlation method for determining the parameters of the inhomogeneities of the ionosphere. Acta Scientiarum Naturalium Universitatis Wuhanensis, No. 6:23-28, 1959. Original in Chinese unchecked. Abstract in English in Science Abstracts of

China: Earth Sciences, Peking, No. 6, 1959, Abstract No. 176.
148

--In applying the correlation method to the study of the parameters of the inhomogeneities in the structure of the ionosphere, it is generally assumed that the contour surfaces of concentric ellipsoids for P , the correlation function of the amplitudes of reflected waves, are similar. In this article, the

authors have taken up a study of the methods of examining

this hypothesis. Examination of the records made both at Wuhan and at Moscow shows that for 70% of the cases the contour surfaces for P are ellipsoidal. But for different values

of P , there are only a few cases which have similar surfaces,

therefore for different contours, the parameters for the inhomogeneities are different. --Authors' abstract.

A-502 Haas, Herbert W. , Telemetering notch antenna 225. Mc/Sec

Aerobee Hi rocket. New Mexico. College of Agriculture and

Mechanic Arts. Physical Science Laboratory, Contract AF

19(604) -409, Scientific Report, No. 2, Feb. 6, 1956. 35 p.

27 figs. (incl. photos. )--The design and development of a 225. Mc/Sec notch antenna for the Aerobee Hi rocket is presented. A detailed radiation pattern study has been made of

the antenna installed in a full scale size rocket mockup. The

radiation patterns have been measured for linear, right circular and left circular polarization. Measured power contour

plots are presented to show the distribution of power in the

aft region of the missile. A number of photographs of the an- tenna, rocket mockup and antenna range facilities are included in this report. Electrical and mechanical details of the an- tenna are shown by the drawings. --Author's abstract.

A-503 Hachenberg, Otto, Sonnentatiqkeit und Ausbreitunq der elektrischen Wellen in der Erdatmosphare. (Solar activity and

propagation of electrical waves in the earth's atmosphere.)

Leipzig, Urania-Verlag, 1955. 27 p. 10 figs. Gesellschaft

zur Verbreitung Wissenschaftlicher Kenntnisse. Vortragsreihe

Naturwissenschaften, Vol. 13. DLC--A pamphlet giving the

basic material, with illustrations, of a popular science lecture

on the ionospheric structure, ionospheric propagation of radio

waves and sounding by impulses or waves, and solar ionizing

influences on the ionosphere. The separate layers (D, E, Fl

and F2) and their formation are treated in detail, and records

are reproduced showing variations and characteristics of these

layers, or of disturbances in the layers. --M. R.

A-504 Hacke, James E. , An approach to the approximate solution

of the ionosphere absorption problem. Institute of Radio Engineers, Proceedings, 36(6): 724- 727, June 1948. 5 figs. , 5 refs. , 24 eqs. DLC--The general problem of group delay and absorption is mathematically discussed. --W.N.
149

A-505 Hafstad, L. R. and Tuve, M. A. , Further studies of the

Kennelly-Heaviside layer by the echo-method. Institute of

Radio Engineers, Proceedings, 17(9): 1513-1522, Sept. 1929.

10 figs. , table 6 refs. DLC--The results of experiments with

multivibrator modulation are discussed. Two 24-hour series

of observations showed a distinct diurnal variation in the

height of the layer. Daytime heights, during a number of

Autumn days in 1928, are given.

A-506 Hagen, John P. (Naval Research Lab. ), Radio tracking, orbit

and communication for the earth satellite. Aeronautical Engineering Review, N.Y. , 16(5):62-66, March 1957. 3 figs.

DLC--A chain of receiving stations, extending from Washington, D.C., to Santiago, Chile, is being set up to create a radio fence which will intercept a satellite each time it circles the earth. This system was chosen to prove that a satellite is in orbit and to derive geophysical information from perturbations of that orbit. --Author's abstract.

A-507 Hagfors, Tor (Norwegian Defence Res. Establishment), Results of scatter measurements at 36 Mc/s over a 1200 Km path. Journal of Atmospheric and Terrestrial Physics, London, Special Supplement, 1957 (Proceedings of the Polar Atmosphere

Sympos ium, Oslo, 1956, Pt. 2), issued 1958. p. 205-209. 5

figs. , 5 refs. , 3 eqs. DLC--The experimental set-up of this

work consisted of a transmitter situated in the south of Norway

and a receiver in the north with a distance of 1130 km separating the two. The results of the experiment include the diurnal

signal variation, the relation between field strength and ionospheric and magnetic data, the angular dependence of scattering cross section, frequency dependence of transmission loss

and the signal fine structure. --N.N.

A-508 Hagfors, Tor (Norwegian Defence Research Establishment,

Kjeller, Norway), Preliminary results of studies of the angu- lar distribution of a VHF ionospheric forward scatter signal.

Journal of Atmospheric and Terrestrial Physics, N. Y. , 12(4):

340-341, 1958. 2 figs. , 4 refs. DLC--This is a brief report on

results obtained at 46. 8 Mc/s over an 1150 km NS path at the

Norwegian Defence Research Establishment, Kjeller, Norway,

Oct. 28, 1958. The experiment described was made in order

to determine the angular spectrum of the received waves by

measuring the correlation over the wavefront. The graphical

presentation of the recording yields valuable information on

the background signal and on the angular spectrum. --W. N.

A-509 Hagfors, Tor, Investigation of the scattering of radio waves

at metric wavelength in the lower ionosphere . Geofysiske

Publikasjoner, Oslo, 21(2), Aug. 1959. 58 p. 6 figs. , 6 +

tables, 16 + eqs. , 41 refs.
150

A-510 Hagg, E.L.; Muldrew, D. and Warren, E. , Spiral occurrence

of sporadic E. Journal of Atmospheric and Terrestrial Physics,

13(3/4): 345-347, June 1959. 2 figs. , table, 5 refs.

A-511 Hagihara, Y. , Rapport du Commite de Recherches ionospheri- ques Japonais de 1946 a .1948. (Committee report of the Japanese ionospheric research 1946-1948. ) URSI, Bulletin No. 63:

8-17, 1950.

A-512 Hajkova, Jaroslava and Mrazek, Jiri (both, Geophysical Inst,

of Czechoslavakia, Akad. d. Wiss. , Prag), Ein Zusammenhang der nachtlichen E-Schicht mit der geomagnetischen Akti- vitat. (Relationship of the nocturnal E-layer to geomagnetic

activity.) Studia Geophysica et Geodaetica, Prague, 3(2):

195-198, 1959. 4 figs. , 4 refs. , eq. Russian summary, p.198.

DWB--Based on observations at the ionospheric observatory at

Lindau (50 39'N, 10 8'E), and the geomagnetic observatory at

Wingst (53°45'N, 9°4'E), the relationship between the night

sporadic E (Es) and geomagnetic activity is shown. More often geomagnetic disturbances result from Es changes than Es

changes follow geomagnetic disturbances. The various types

of geomagnetic phenomena must be tested separately: geomagnetic storms, bay disturbances and pulsations. --M. R.

A-513 Halley, R. ; Lepechinsky, D, and Mouchez, P. , Comparison

des methodes de prevision a long terme du CRPL du SPIM . (Comparison between the CRPL's and SPIM's methods of long

range forecast.) Annales des telecommunications, Paris, 13

(9/10) -.254-264, Sept.- Oct. 1958. 6 figs. , 7 refs. DLC--Recall of the leading ideas of the two principal methods used for

studying ionospheric propagation; the method of the Central

Radio Propagation Laboratory (CRPL) and that of the Service

de Previsions Ionospheriques Militaire (SPIM). The authors

s how the points through which these methods are divergent.

The second part of the article introduces and gives an interpretation of the differences appearing in forecast established

through the two methods although starting from the same physical parameters of the ionosphere. --A. V.

A-514 Hanson, G.H. ; Serson, H. V. and Campbell, W. , Maximum

usable frequencies and lowest usable frequencies for the path

Washington and Resolute Bay. Journal of Geophysical Research, 58(4):487-491, Dec. 1953. 3 figs. , 3 refs. DLC--The

standard frequency transmissions of WWV were monitored at

Resolute Bay for one year. Using a method developed by

SCOTT, maximum usable (MUF's) and lowest usable frequencies (LUF's) have been obtained for the path Washington to

Resolute Bay for that period. Comparison with the predictions

made by the Central Radio Propagation Laboratory in Washington
151

indicates that the predicted MUF's are too low during the

night and, for some months, too high during the day. The

LUF's are lower than would be expected if the propagation

were all by one reflection from the F2 layer. --Authors' abstract.

A-515 Harang, Leiv (Norwegian Defence Res. Establishment), Results of ionospheric drift measurements in Norway. Journal of

Atmospheric and Terrestrial Physics, London, Special Supplement, 1957 (Proceedings of the Polar Atmosphere Symposium,

Oslo, 1956, Pt. 2), issued 1958? p. 23-32. 12 figs. , ref.

DLC --During 1953-1955 E-layer drift measurements were made

in Norway according to the Mitra method. The graphs presented show the diurnal variations during the year together

with the annual means for the two years. Values of drift for

Kjeller, Norway are compared with similar recordings from

Washington and Cambridge. The wind vectors for Kjeller are schematically illustrated together with the distribution curves. --N.N.

A-516 Harang, L. , Scattering of radio waves from great vertical

distances. Terr. Magn. Atmos. Elect. 50, 287-296, Dec.

1945. --Using a pulse-transmitter of high power, scattered re- flections corresponding to virtual reflection-distances of 500

to 2, 500 km have been obtained. The test frequencies used

(10-11 mc/s) were usually greater than the critical penetration

frequencies of the F2 layer. Records on a fixed frequency

over a number of days have been taken in order to study the

diurnal variation and dependence on geomagnetic activity and

aurora. Four different phases in the diurnal variation have

been recorded. During the two day phases it has been shown

that the scattered reflections cannot come in vertically as they are not cut off by the F layer. During the zenith at

heights of 500 and 800 km, small geomagnetic disturbances

increased the scattering at these heights. Stronger perturbations were accompanied by scattering from down to 100 to 200

km.

A-517 Hardwick, B. , Two cases of large F2 region disturbance as- sociated with small magnetic disturbance . Journal of Atmospheric and Terrestrial Physics, 3(6):347-349, July 1953. fig.,

ref. MH-BK-- Large but local ionospheric disturbances were re- corded on International Magnetically Quiet Days, at Canberra

on Oct. 26-27, 1947 and at Chungking, Palmyra and Rarotonga

on Jan. 11, 1947. -C. E. P. B.
152

A-518 Hamischmacher, Ewald, Prevision de la propagation ionosphericme pour les distances superieures a 10, 000 km. (Forecasting ionospheric propagation for distances over 10, 000 km.

)

Academie des Sciences, Paris, Comptes Rendus, 237(18): 1071-

1073, Nov. 2, 1953. 3 refs. DWB--A method is outlined lor

determining mixed trajectories of long-distance ionospheric

radio wave propagation. The method accounts for the fact

that radio waves follow trajectories adapted to ionospheric

conditions. The accuracy of a propagation forecast for a distance of 17, 000 km was confirmed in experimental operation.

-G. T.

A-519 Harnischmacher, Ewald and Rawer, Karl, L 'interpretation des

observations du vent ionospherigue suivant la methode des

"fadings. " (Interpretation of ionospheric wind observations

by the "fading" method. ) Academie des Sciences, Paris, Comptes Rendus, 243(9): 747-750, Aug. 27, 1956. table, 4 refs.

Also their: Resultats d 'observations systemaiigues du vent

ionospherigue dans la region E. (Results of systematic observations of ionospheric wind in the E region. ) Ibid. , 243(10):

782-783, Sept. 3, 1956. DLC-KRAUTKRAMER's method of

ionospheric wind determination by means of comparison of fadings using three antennas, is found to be more accurate than

anticipated on the basis of theory. Regular observations made

by this method at Neuf-Brisach between Dec. 1955 and Aug.

1956 show average monthly wind velocities of 60-100 m/s in

winter and 40-70 m/s in summer. Wind direction undergoes

two complete revolutions in 24 hrs on 80% of all days in winter and one revolution at night in summer. --G. T.

A-520 Harnischmacher, E. and Rawer, Karl, Ergebnisse ionosphar- ischer Windmessungen in der E-reqion. (Results of ionospheric wind measurements in the E-region. ) Beitrage zur Physik

der Atmosphare, Frankfurt a. M. , 29(4): 253-268, 1957. 13

figs., 4 refs. German, English and French summaries p. 253.

DWB, DLC--The ionospheric drift in the E-layer is observed

with KRAUTKRAMER's fading method. The evaluation is

simply based on the median of several successive determinations of the apparent drift-vector. Results in terms of amplitude and direction are given in graphical form from Nov. 1955

until Oct. 1956. -Authors' abstract.

A-521 Harnischmacher, E. , Observation du vent ionospherigue . (Observation of ionospheric wind. ) Annales des Telecommunications, Paris, 12(5): 159-161, May 1957. 6 figs. , 2 refs. DLC

—Measurements of ionospheric winds made by the method of

fadings at Neuf-Brisach, France (since Nov. 1955), at Cambridge, Eng. , and at Kootwijk, Netherlands, are compared and

found to be in fair agreement in respect to direction but less

good for speed. --G. T.
153

A-522 Hamischmacher, E. , Ionospheric drifts in Puerto Rico obtained by the method of analysis developed in Neuf-Breisach.

Puerto Rico Univ. College of Agriculture and Mechanic Arts,

Contract AF 19(604) -2036 (Study of ionospheric winds), Scientific Report No. 5, Dec. 1958. 15 p. 28 figs. , table. DWB

--The method of similar fades for determination of ionospheric

drifts with spaced receivers is first discussed together with

modification and simplifications in the calculating procedure

introduced at Neuf-Breisach. The records used and their analysis according to this method are then discussed. The re- sults are then set forth together with comments on certain re- gularities observed in the ionospheric drifts. --Author's abstract.

A-523 Hamischmacher, E. and Rawer, K. , Ionospharische Wind- messungen in der E-reqion Nov. 1956 bis Jan. 1957. (Ionospheric wind measurements in the E region Nov. 1956 - Jan.

1957. ) Beitrage zur Physik der Atmosphare, Frankfurt, A. M.

,

31(1/2): 131-134, 1958. 3 figs. DWB, DLC. Continuation of

the measurements published Ibid. , 29(4): 153-168 (see 520).

Graphs giving mean hourly ionospheric wind velocities in

m/sec in the E layer obtained during November and December

1956, and January 1957, are presented. —I. L. D.

A-524 Hamischmacher, E. and Rawer, Karl, Drift observations

evaluated by the method of "similar fades". Journal of Atmospheric and Terrestrial Physics, London, 13(1/2): 1-16, Dec.

1958. 12 figs. , 12 refs. , 16 eqs. DLC--A regular interference

model of the fading pattern is considered as opposed to the

usually accepted purely random model. It would appear that

some of the observed features are well explained by a model

which is intermediate between these two types insofar as re- gular interference perturbations are concerned, but one in

which a finite lifetime for the irregularities is supposed. It appears that with the "similar fade" analysis there is a marked

tendency to select those periods where the interference is

quite regular and the rather small angular dispersion found in

most sets of observations can thus be explained. The observed big dispersion of the speed is at least partially due to a small vertical component of the movement. --Authors' abstract.

A-525 Harris, K. E. (Dir. of Development, A. C. Cossar, Ltd. ), Secondary radar applications . Communications and Electronics,

London, 1(3):57-61, Dec. 1954. photos, diagr. , table. DWB

--The various uses for radar are outlined and secondary uses

such as for upper air wind measurement emphasized. Illustrations of use of Mullard Radar Sonde System including diagram

of complete radar wind, radar sonde and ground station equipment are presented, with specifications listed. —M. R.
154

A-526 Hartman, L. M. and Haviland, R.P. (both, Gen. Elec. Co.),

A satellite propagation experiment. (In: Van Allen, James A.

(ed. ), Scientific uses of earth satellites. Ann Arbor, Univ.

of Michigan Press, 1956. p. 268-275. table. ) DWB--A satellite ionosphere and propagation experiment is proposed. Satellite equipment consists of a low-power c-w transmitter operating on a frequency near the ionosphere cut-off frequency

corresponding to maximum geometric line-of-sight distances

from the satellite. Statistical data on coverage are sought by

enlisting aid of operators in the Radio Amateur Service. Particular measurements to be made at specially equipped stations are reviewed. --Authors' abstract.

A-527 Hartsfield, W. L. and Silberstein, R. , A comparison of CW

field intensity and backscatter delay. Institute of Radio

Engineers, Proceedings, 40(12): 1700-1 706, Dec. 1952. 6 figs.,

14 refs. DWB--The relationship of back-scatter to skip phenomena was studied for several months by comparing the field

intensity of 15, 000 kc/s (15 Mc/s) W. W. W. signals received

at White Sands Proving Ground, New Mexico with recorded

delay times of the back-scatter received over the 2700 km distance at Sterling, Va. The results are given in A-scope photos,

graphs and curves. Back-scatter data may provide an indicator even better than the direction finder technique in forecasting disturbances. --W. N.

A-528 Harvard College Observatory. Rocket Panel , Pressures, den- sities, and temperatures in the upper atmosphere. Physical

Review, 88(5): 1027-1032, Dec. 1, 1952. 3 figs. , 3 tables.

DWB--Smoothed curves of pressure, density and temperature

from to 220 km from results of 68 V-2, 63 Aerobee and 7

Martin Viking rocket ascents at White Sands, N. Mexico.

The panel is not so foolish as to call this a standard atmosphere, but merely the combined results of numerous investigations as of Jan. 1952. Temperature calculations by many

groups are tabulated and the weighted means and adopted

values shown. Below 30 km values are obtained from radiosonde ascents at White Sands. No correlation has been made

for dissociation of 02 > 80 km, nor for seasonal effects, daylight effects or instrumental errors (the latter may be greater

than real variations). Other soundings with rockets (on the

equator) or by meteors and acoustical means in the Arctic

(Fairbanks) and tropics are related to these data. The whole

matter is still pending. --M. R.

A-529 Harvey, J. A. (Electrical Eng. Dep. , Univ. of Sydney), Move- ment of sporadic E ionization. Australian Journal of Physics,

Melbourne, 8(4):523-534, Dec. 1955. 10 figs. , table, 13 refs.

DLC--
155

The horizontal movement of patches of daytime sporadic E

ionization has been observed by using a system of spaced

pulse transmitters and a central recorder. The directions of

movement are mainly towards the north and west, with speeds

mainly between 40 and 80 m/sec. These velocities differ in

direction from the F region disturbances recorded at the same

time and have only about half the speed. —Author's abstract.

A-530 Harwood, J. , Spaced-receiver experiments on radio waves of

19 km wavelength. Institution of Electrical Engineers, Proceedings, Pt. 4, 101(7): 183-196, Aug. 1954. 3 figs. , 11 refs.

DLC—The signals from the Post Office sender GBR at Rugby on

a frequency of 16 kc/s (wavelength 19 km) were received at a

distance of about 100 km at two sites whose distance apart

was, on one occasion, 15 km, and on another occasion 40 km.

Examination of the fading records of the amplitude of the wave

reflected from the ionosphere showed that it consisted of a

steady component on which was superimposed a randomly varying component. The correlation between records at two points

15 km apart was about 0. 8, and at 40 km was 0. 35. The time

variations of the random component could have been produced

by reflection from scattering centers in the ionosphere which

moved with random velocities having an r. m. s. value of about

8 m/s in the line of sight, or which drifted steadily with a velocity of about 100 m/s in a direction predominently east-west.

-•Author's abstract.

A-531 Harwood, J. (Radio Research Station, Eng. ), Atmospheric

radio noise at frequencies between 10 KC/S and 30 KC/S.

Institution of Electrical Engineers, London, Proceedings, Pt.

B, 105(2) :293-300, May 1958. 9 figs. , 2 tables, 4 refs. , 11

eqs. Abstract in Institution of Electrical Engineers, Journal,

4(41): 265, May 1958. DLC-Measurements of the characteristics of very-low frequency atmospheric noise in southern England have been made with automatic equipment during the last

few years. The results are described in terms of statistical

parameters of the envelope at the output of a narrow-bandwidth

receiver (300 c/s between 3 dB points). A 2-form structure of

the envelope is described. Intensity and structure variations.

with frequency and bandwidth were examined.-- From Author's

abstract.

A-532 Haselgrove, J. (Univ. Math. Lab. , Cambridge), Oblique ray

paths in the ionosphere. Physical Society of London, Proceedings, Pt. B, 70(7): 653-662, July 1, 1957. 6 figs. , 6 refs.

,

eqs. DLC, DWB—An electronic digital computer has been used

to calculate ray paths in a parabolic ionospheric layer when

the waves are incident in the plane of the magnetic meridian.

This is a special application of a very general method. The
156

results of the calculations are compared with what would be

deduced from vertical soundings by the standard approximations of using Martyn's and Breit and Tuve's theorems as if there were no field. --Author's abstract.

A-533 Haubert, A. , Echos radioelectriques observes sur la houle a

la station de sondaqes ionospheriques de Casablanca. (Radio

echoes from sea waves observed at the ionospheric station of

Casablanca.) Annales de Geophysique, Paris, 14(3): 368-372,

July/Sept. 1958. 7 figs., 3 refs. , 7 eqs. DLC--Echoes thought to be reflected from virtual heights lower than 100 m (D re- gion of the ionosphere), have been recorded since the end of

1953, at the ionospheric station of Casablanca. The particular forms of these echoes suggested possible reflections from

sea waves, the ionospheric station being located near the sea

shore. The results of experiments are in agreement with the

theory of a Doppler effect of sea waves. Consequently, the

measurements of sea wave periods and lengths, from distances

as far as 100 km, would be possible by means of ionospheric

sounders equipped with special devices. --Author's abstract.

A-534 Haubert, A. , Le renforcement du champ en ondes longues et

les evanouissements en ondes courtes. (Intensification of

field strength of long waves and the fading of short waves.

)

Journal of Atmospheric and Terrestrial Physics, 13(3/4) :379-

381, Feb. 1959. 2 figs. , ref

.

A-535 Haviland, R. P. (Special Defense Projects Dept. , General

Electric, Philadelphia), What the future holds for the earth

satellite. General Electric Review, Schenectady, N.Y.

,

59(5):10-16, Sept. 1956. 10 figs., 2 tables. DLC-The possible orbits and respective areas of the earth which could be

seen from a satellite at 300 mi, 4000 mi; or the areas over

which a satellite at 22, 300 mi height could relay radio or TV

signals from hemisphere to hemisphere or within the Western

Hemisphere are shown on maps. Tables give distances of

vision, field of view, etc. for heights of 257, 620, 1210,

2222, 4000, 7650, 19, 000 and 22, 300 mi. Weather charting

and forecasting possibilities are also considered. Hurricanes,

clouds, albedo and solar radiation could be measured or observed from such a station. --M. R.

A-536 Haycock, Obed C. , Experimental plan and instrumentation

for the determination of the electron density in the ionosphere.

Utah. Univ. Upper Air Research Laboratories, Contract AF

19(604) -384, Scientific Report, No. 1 (and) Final Report on the

Contract, June 1, 1952-April 30, 1957, pub. May 21, 1957.

129 p. 37 figs. , foot-refs. --
157

A complete summarization of the essential results of a 10 year

study of the electron density of the ionosphere (E layer to 37

km) by pulse transmissions at or slightly above the critical

frequency (F ) of the layer penetrated by the sounding rocket,

compared with the non-delayed signal at a frequency so high

it would not be affected by the ionization of the layer in question. Both upward and downward transmissions were used.

Equipment was automatic but reduction of data was tedious.

Plan of experiment, of circuits, changes in plans as time passed, details of operation and results are presented graphically

and described. Electron density increases markedly from 85

km (0) to 2 X lOH per m3 at 115 and 130 km. --M. R.

A-537 Heading, J. and Whipple, R. T. P. , The oblique reflection of

long wireless waves from the ionosphere at places where the

earth's magnetic field is regarded as vertical. Royal Society

of London, Philosophical Transactions, Ser. A, 244(887) :469-

503, April 3, 1952. 24 figs., 2 tables, 15 refs. , 92 eqs.

DWB--"Equations are developed for the electromagnetic field

in a horizontally stratified medium of varying electron density,

the presence of a vertical external magnetic field and the collision frequency of the electrons with neutral molecules being

taken into account. " In certain conditions the ionosphere

splits into two, for each of which the equations can be solved

exactly. --C.E. P.B.

A-538 Heading, J. , The reflexion of vertically- incident long radio

waves from the ionosphere with the earth's magnetic field is

oblique. Royal Society of London, Proceedings, Ser. A,

231(1186) :414-435, Sept. 6, 1955. 8 figs., 11 refs. , 89 eqs.

DWB—Approximate equations are developed for the reflexion

of plane electromagnetic waves from a horizontally stratified

anisotropic ionosphere, when the earth's magnetic field is in

an arbitrary direction. Two distinct regions of height arise in

the theory, each governed by its respective equations of propagation. For the special case of vertical incidence in an oblique magnetic field when the distribution of electron density

is exponential, the equations for the lower region are solved

analytically in terms of hypergeometric functions. The equations for the upper region are solved in terms of generalized

hypergeometric functions under more general conditions, namely for oblique propagation whea the plane of incidence coincides with the magnetic meridian. Explicit expressions in

terms of F functions of complex arguments are obtained for the

reflexion and transmission coefficients of the lower region,

and for the reflexion and conversion coefficients of the upper

region. The theory is illustrated numerically by a typical

model. --Author's abstract.
158

A-539 Heaviside, Sir Oliver and others. Telegraphy. Encyclopaedia Britannica, London & Edinburgh, Adam and Charles Black,

1902. 10th ed. v. 9 (i. e. v. 33 of 9th ed.), p. 213-235.

refs. , 20 eqs. DLC—On p. 215 of this comprehensive treatise

on the recent discoveries in theory of electromagnetic propagation in air, sea, earth and wires, and applications to wireless and land and submarine telegraphy, the author hints at

the possibility of "a sufficiently conducting layer in the upper

air" to serve as one plane of a wave guide— the other plane

being the sea surface. Then the theoretical equations for propagation of signals between two such guides are developed.

It was years before the author completely accepted his own

theory as there was no experimental proof other than the fact

of transatlantic propagation up to 2100 mi, but with legible

messages received at only 700 mi by day and 1500 mi by night

(p. 233).--M.R.

A-540 Hedlund, B. A. and Edwards, L.C., Polarization fading over

an obligue incidence path. Institute of Radio Engineers, Transactions, AP-6:21-25, Jan. 1958.

A-541 Heightman, D.W. , Propagation of metric waves beyond opti- cal range. Institution of Radio Engineers, Journal, 10( ):295,

1950. —A qualitative survey of tropospheric and ionospheric

wave propagation in the frequency band 30-200 mc. Theoretical treatment is limited to explanations of the basic principles involved. A knowledge of the easily recognized meteorological conditions associated with variations in tropospheric

propagation is useful in short-term prediction of radio conditions. Extended ranges are, in general,, of little practical

value owing to interference from distant transmitters. A selection of long-term observations over various land and sea

paths, both tropospheric and ionospheric, is presented in

graphical form and results are discussed.

A-542 Heitler, Walter, The guantum theory of radiation. 3rd ed.

Oxford, Clarendon Press, 1954. 430 p. 32 figs. , 13 tables,

numerous refs. and eqs. International Series of Monographs

on Physics. DWB--This 3rd edition of HEITLER 's text on quantum theory is greatly enlarged, but additions have been confined to the electrodynamics of electrons and positrons; while

the electrodynamics of mesons and nucleons, and nuclear physics have been omitted. The major sections are: I. Classical

theory of radiation, II. Quantum theory of pure radiation field,

III. Electron field, IV. Perturbation theory, V. Radiation

processes, VI. Radiative corrections and VII. Penetrating

power of high energy radiation. Emission and absorption, line

breadth, dispersion, Bremsstrahlung, etc. are discussed in

Sec. V and action of cosmic rays on matter due to collision
159

(cascade showers, etc. ) under Sec. VII. A subject and author index are provided. --M. R.

A-543 Helliwell, R.A. , Ionospheric virtual height measurements at

100 kc. Stanford University, Electronics Laboratories, Contract CST-10751. Summary, Aug. 1948.

A-544 Helliwell, R. A. ; Mallinckrodt, A. J. ; Kruse, F. W. , Jr. ; and

Wambaganss, B. A. , Pulse studies of the ionosphere at low

frequencies . Stanford University, Electronics Research Laboratories, Contract CST-10751, Technical Report, March 1950.

A-545 Helliwell, R. A. ; Mallinckrodt, A. J. ; Kruse, F. W. , Jr. and

Wambasganss, B. A. , Pulse studies of the ionosphere at low

frequencies . Stanford Univ. Electronics Research Laboratory,

Contract CST-8966, July 1, 1948-June 30, 1949. March 15,1950.

132 p. 55 figs. , eqs. DWB--A voluminous report of pulse

studies made at Stanford on low frequencies (100, 325, 350,

560, 850, 1120 and 1415 kc) from July 1948 to Sept. 1949.

Weak echoes occurred from 35-85 km but those below 65 km

are of doubtful origin. Apparatus for transmitting and receiving, notes on low level echoes, diurnal variation, splitting,

vertical gradients of ionization, night time critical frequency

of E region, diurnal and annual height trends, polarization,

sunrise effect and sferics are treated in detail. The ionospheric storm of May 11-13, 1949 is analyzed and discussed

at length. --M. R.

A-546 Helliwell, R. A. ; Mallinckrodt, A. J. and Kruse, F. W. , Fine

structure of lower ionosphere. Geophysical Research v. 56,

March 1, 1951. p. 53-62. --Pulse soundings of ionosphere at

vertical incidence taken at 100 and 325 kc show pronounced

splitting of echoes received at night; most echo components

found to lie between about 90 and 130 km; it appears that

lower ionosphere contains at night a system of reflecting

strata at discrete heights, capable of both reflecting and transmitting incident electromagnetic energy. --E. I. S.

A-547 Helliwell, R. A. , Sporadic E stratification and correlation

with low-frequency soundings. Institute of Radio Engineers,

Transactions, PGAP-3: 140-142, Aug. 1952.

A-548 Helliwell, R.A. (Stanford Univ. , Stanford, Calif.), Graphical solution of sky-wave problems. Electronics, 26(2) :150,

152, Feb. 1953. 2 figs. DLC-If any two of the following factors are known: 1) great circle distance between transmitter

and receiver, 2) virtual height of reflection, 3) equivalent

path distance between transmitter and receiver, 4) angle of

departure and 5) angle of incidence at the ionosphere, the
160

other three are easily found by the use of a sky wave transmission chart, the use of which is shown by examples. --W. N.

A-549 Helliwell, R.A. ; Crary, J. H. ; Smith, R.L. ; (all, Radio prop.

Lab., Stanford Univ. , Stanford, Calif. )^ and Pope, J. H. (Geophysical Inst. , Univ. of Alaska, College, Alaska), The

"nose" whistler-a new high-latitude phenomenon. Journal of

Geophysical Research, Wash., D.C., 61(1) -.139-142, March

1956. fig. , 4 refs., 2 eqs. DLC--A peculiar type of whistler

recorded at College, Alaska on July 10, 1955 (65° lat) not detectable by ear is illustrated and the origin speculated on. A

general form of Eckersley's dispersion law gives a predicted

form of impulse similar to the observed nose whistlers. The

usual whistlers are thought to be the descending portion of

nose whistlers. They may give information on conditions in

the ring current region and explain the dawn chorus. --M. R.

A-550 Helliwell, R.A. (Stanford Univ. Calif. ) and Morgan, M. G.

(Dartmouth College, New Hamp. ), IGY whistler observations.

Science, Wash., D.C., 123(3201): 788, May 4, 1956. DLC--

Notes on the program of synoptic observation of whistlers in

the Northern and Southern Hemispheres, respectively, as outlined at the Boulder, Colo, meeting Feb. 14-16, 1956 for the

IGY, 1957/8. Whistlers are thought to be signals from lightning discharges that follow longitudinal lines of magnetic

force and where the high frequencies arrive ahead of the low,

producing a descending note or whistle. They are believed to

follow a path 2 or 3 earth radii out in space, so would give

indications of ionization at very high altitudes. Stations proposed are listed in 3 groups: The Atlantic, Pacific, and MidContinent Group. --M. R.

A-551 Helliwell, R. A. , Low frequency propagation studies, Pt. I, whistlers and related phenomena. Stanford University, Electronics Research Laboratories, Contract AF 19(604) -795, Final

Report, Dec. 1956.

A-552 Helliwell, R. A. , Low frequency propagation studies, Pt. II, Low and medium propagation studies. Stanford University,

Electronics Laboratories, Contract AF 19(604) -795, Final Report, Sept. 1956.

A-553 Helliwell, R. A. and Gehrola, E. (both, Radio Prop. Lab.

,

Stanford Univ. ), Observations of magneto-ionic duct propa - gation using man-made signals of very low frequency. Institute of Radio Engineers, Proceedings, 46(4): 785- 787, April

1958. 2 figs. , 6 refs. DLC--A unique mode of very low frequency radio transmission (from Annapolis, Md. to Cape Horn,

South America) is reported; its close similarity to whistler
161

propagation is claimed to provide new evidence in support of

the ECKERSLEY-STOREY theory of whistlers. Details of the

apparatus and operation are given and records obtained are presented. The technique (being controlable) is considered

superior to the whistler method for the study of the outer ionosphere. --G. T.

A-554 Henissart, Martha, Low frequency noise in the range 0. 5-

20 cycles per sec. Nature, London, 172(4380): 682-683, Oct.

10, 1953. 4 figs. , 3 refs. DWB--Describes measurements in

Massachusetts and New Mexico; records of noise storm and

quiet periods are shown. Storms were frequent and are often

correlated with ionospheric storminess, K-index, and solar

radio noise (including a peak at lags of 29 and 37 days). A

regular diurnal variation was found. --C. E. P. B.

A-555 Hennessey, James J. and Torres, J. S. , Experimental ionosph- eric observations of the solar eclipse of June 20, 1955 at Baguio City, Philippines. Special supplement to: Journal of Atmospheric and Terrestrial Physics,

A-556 Hepburn, F. and Pierce, E. T. , Atmospherics with very lowfrequency components. Nature, London, 171(4358) :837-838,

May 9, 1953. 4 refs. DWB-The 'slow tails' (100-500 c/s)

parameters of atmospherics: t, time between start of main

oscillation and commencement of slow tail, and quarter cycle

7~/4 of the tail are represented for distances D up to 5000 km

by t = K(D - D ) and //4 = T~+ cD; D = 1000 km and T~

500 /£ sec. By day K = 0. 33 and c = 0. 23; by night k = 0. 13

and c = 0. 08. The results indicate propagation between earth

and an equivalent homogeneous ionospheric layer, height 65

km and conductivity 5 X 10^ e. s. u. by day, 90 km and 11 X

103 by night. --C. E. P. B.

A-557 Hepburn, F. , Atmospheric waveforms with very low-frequency

components below 1 kc/s known as slow tails. Journal of Atmospheric and Terrestrial Physics, 10(5/6) :266-287, 1957. 10

figs., 3 tables, 21 refs. DWB—Origin of "slow tails" is discussed. Recent observations of form, magnitude, quasi-period

and delay of slow tails are described and their theoretical ex- planation in terms of source and propagation set out. Examples

of slow tails are illustrated and diurnal variation with respect

to sunset at source plotted. Amplitude increases from day to

night, quarter period by day and with storm distance. Delay

increases more rapidly by day than night and more rapidly than

quarter periods. Theory of origin is discussed; day and night

ionosphere parameters are evaluated for heights of 50-90 km.
162

A-558 Hepburn, F. (Physics Dept. , Univ. of Nottingham), Classification of atmospheric waveforms. Journal of Atmospheric

and Terrestrial Physics, London, 12(l):l-7, 1958. 3 figs. , 12

refs. DLC--The desirability and requirements of a systematic

classification of atmospheric wave forms are discussed. An

observational scheme is suggested and interpreted in terms of

known properties of the discharge and propagation mechanisms.

This data is reviewed to clarify application of the scheme to

individual wave forms. The relationship of the classification

to previous inadequate groupings is indicated. --Author's abstract.

A-559 Heritage, J.L. ; Weisbrod, S. and Fay, W. J. , Evidence for a 200 megacycle per second ionospheric forward scatter mode

associated with the earth's magnetic field. Journal of Geophysical Research, 64(9): 1235-1241, Sept. 1959. 8 figs.

,

4 refs.

A-560 Hess, H. A. , Kurzwellenausbreitung uber Polargebieten. (Short wave propagation over polar regions. ) Das Elektron,

3(6):218-226, June 1949. 8 figs. , 12 refs. eqs. DLC--The

"split-up" Morse signals characteristics for Polar regions due

to heavy changes in the reflexibility of the ionospheric layers

were investigated and analyzed (1942-1945). Oscillograph re- cordings of signals photographed in slow motion technique are presented and some possible ways to overcome the splitting are offered. It is concluded that short-wave propagation is

bound to several reflections between ionosphere and ground.

--W.N.

A-561 Hess, H. A. , Investigations of high-frequency echoes, Pt. 3.

Institute of Radio Engineers, N. Y. , Proceedings, 40(9):1Q65-

1068, Sept. 1952. 4 figs. , 6 refs. DLC--The author gives a detailed account of radio wave propagation carried out in Germany in Nov. 1944, on a frequency of 19, 947 kc. First and

second circuits (around the globe) and signals reflected from

the ionosphere were recorded and timed. Original records of

the received signals are reproduced and time-amplitude curves

presented. Around-the -globe trajectories of radio waves are shown in a diagram representing them as a beam of great circle lines with intersections at antipodal points. The ratio between the circuit period and the height of the reflecting F2

layer is graphically represented. (For Pts 1 and 2 see I. R. E.

,

Proceedings, 36:981-992, Aug. 1948 and 37:986-989, Sept.

1949. )-G.T.
133

A-562 Hibberd, F. H. , Theoretical resonance curves in the gyrointeraction of electromagnetic waves in the ionosphere. II Nuovo Cimento, 10(4): 380-385, April 1, 1953. 2 figs. , footrefs. Italian summary p. 385. DLC--In a recent communication Dr. Motzo has considered the gyro-interaction of radio

waves in the ionosphere when the disturbing wave is incident

vertically. She concludes that for this case one would expect

to observe always a single maximum in the index of interaction as the frequency of the disturbing wave is varied through

the gyro -frequency. It is possible to show that with larger

approximations in the calculations either single or double

maxima may occur and that there is little difference in the

general shape of the resonance curves resulting from vertically incident and obliquely incident disturbing waves. A

qualitative outline is given of the theory of gyro-interaction

of V. A. Bailey. —Author's abstract.

A-563 Hibberd, F. H. , Ionospheric self-interaction of radio waves.

Journal of Atmospheric and Terrestrial Physics, 6(5):268-279,

May 1955. fig. , 12 refs. , 28 eqs. DWB-A theory is developed for the self-interaction of a modulated continuous wave

in the ionosphere. In general, self-interaction will result in a reduction of modulation of a modulated wave and in the generation of harmonics of the original modulation frequency in

its passage through the ionosphere. The effects should be

greatest for a high-power, medium- to low -frequency wave with

low modulation frequency. The magnitude of the demodulation

appears to be sufficiently large to measure. It is possible to

determine from it the electron collision frequency in the lower

E layer. Effects near the gyro-frequency have not been considered. --Author's abstract.

A-564 Hibberd, F. H. , Self-distortion of radio waves in the ionosphere, near the gyro frequency. Journal of Atmospheric and

Terrestrial Physics, 11(2): 102-110, 1957. table, 9 refs. , 14

eqs. DWB--In a previous paper (1956) the self-distortion (or

self -interaction) of a low frequency radio wave in the ionosphere was considered, neglecting the earth's magnetic field,

and it was shown that self -distortion results in a small reduction of the modulation depth of a modulated wave. The theory

is extended here, with the inclusion of the magnetic field, for

frequencies near the gyro frequency. It is shown that the re- duction in modulation depth varies only slowly with wave frequency near the gyro frequency, and shows no resonant-like

variation. The reduction is proportional to the power-radiated,

is greatest for low modulation frequencies and decreases rapidly as the modulation frequency is increased. With 100 kW

radiated, the fractional reduction in modulation depth of a
164

modulated gyro wave is expected to be of the order of 1 part

in 100. Recent experiments that have been claimed to have

demonstrated large self distortion effects near the gyro frequency are discussed. --Author's abstract.

A-565 Hibberd, F. H. , The Faraday fading of radio waves from an

artificial satellite. Journal of Geophysical Research, 64(8):

945-948, Aug. 1959. figs. , 5 refs.

A-566 Higgs, A.J. (Australian Sci. Liaison Off. , Wash., D.C.),

Radiophysics in Australia. Science, 117(3031) :3, Jan. 30,

1953. DWB--The Radiophysics Lab. in Sydney began in 1949

as a wartime radar research establishment but is now famous

for its peacetime work in radio astronomy and radar and is concerned with ionospheric and upper atmosphere investigations.

Work in Australia on cloud physics and "rain making" was

spectacular in the early stages (1947). Recently, good re- sults have been obtained by the Laboratory in studies of rain

from non-freezing clouds, and of the relative importance of

coalescence in raindrop formation. --M. R.

A-567 Hill, R.A. and Dyce, R. B. (both, Stanford Res. Inst. , Menlo

Pk. , Calif. ), Some observations of ionospheric Faraday rota - tion on 106. 1 Mc/s. Journal of Geophysical Research, Wash.

D.C., 65(1): 173-176, Jan. 1960. 6 figs. , table, 4 refs. , 4

eqs. DWB, DLC--The polarization twist imposed on 106. 1

Mc/s radio waves by the ionosphere has been investigated by

using the moon as a passive reflector, the purpose being to

determine the total electron column density even at altitudes

above the known ionosphere. Because the antenna is capable

of being continuously directed at the moon for 12 consecutive

hours, observations are possible from the pre-dawn ionization

minimum to the noon-time maximum. A true -height profile computed from vertical-incidence ionosonde data of Sept. 16, 1957,

suggests that the total electron content throughout the entire

ionosphere is not a constant factor of the integrated electron

content computed up to the level of maximum ionization density. --Authors' abstract.

A-568 Hineken, F. W. and Bruin, F. (Zeeman Lab. , Amsterdam Univ.

,

Netherlands), Some measurements on refractive indices of

gases in the microwave region. Physica, Amsterdam, 20(6):

350-360, June 1954. 4 figs., 2 tables, 16 refs. DWB, DLC--

A method is described to measure refractive indices of gases

at atmospheric pressure and at a frequency of 25, 000 Mc/s.

The method is based on the change in resonance frequency of a cavity, first filled with a reference gas (nitrogen) and after

that with the gas of which the refractive index is to be determined. However, instead of measuring the frequency change

of a fixed cavity the authors measure the change in length of
165

the cavity, necessary to keep it tuned in both cases to the

frequency of the (6, 6) inversion line of ammonia. Subsequently the reading with a nitrogen filling is compared to the

one of the evacuated cavity, so that all refractive indices are obtained with respect to vacuo. Results of these measurements for ten gases are given. As the absorption is extremely small and the inaccuracy of measurements of refractive indices amounts to one or two parts in 10" for these gases, the

introduction of a complex refractive index is found to be un- necessary. --Author's abstract.

A-569 Hines, CO., Wave packets, the Poynting vector, and energy

flow, Pt. 4, Poynting and Macdonald velocities in dissipative

anisotropic media (conclusion). Journal of Geophysical Research, 56(4): 535-544, Dec. 1951. llrefs., 24 eqs. DLC--

Deals with the path of electromagnetic energy flow in media

of complex nature (propagation of radio signals in the ionosphere). Direction obtained by POYNTING 's or MACDONALD 's methods shows a discrepancy with that found by the probably

more reliable packet method. --A. A.

A-570 Hines, CO., Electron resonance in ionospheric waves.

Journal of Atmospheric and Terrestrial Physics, London, 9(1):

56-70, July 1956. 3 figs. , table, 10 refs. , 43 eqs. DWB--

Large-scale travelling disturbances, now frequently observed

in ionospheric F layer, are interpreted in terms of an electron

resonance. This phenomenon arises when an initial atmospheric disturbance sets the electrons into natural modes of oscillation, and the resultant increase of electron displacements

then enhances the likelihood of detection by present (radio)

techniques. Certain qualitative features of the observed disturbances can be explained on this basis, and a quantitative

comparison provides estimates for several ionospheric parameters which are in good agreement with the values expected.

Further application of an improved theoretical development may

well provide an extremely useful method of investigating the

physical properties of the ionosphere. --Author's abstract.

A-571 Hines, CO., Heavy-ion effects in audio-frequency radio pro- pagation. Journal of Atmospheric and Terrestrial Physics, 11

(l):36-42, 1957. 2 figs., 5 refs. , 16 eqs. DWB--The usual

theory of whistler propagation, in which the effects of electrons alone are considered, leads to the conclusion that whistler ray directions cannot differ markedly from the direction of

the geomagnetic field. When the effects of heavy ions are considered, however, it is found that all directions of propagation are possible at audio frequencies, and that the disper-
166

sion of frequencies takes place in opposite senses for longitudinal and transverse propagation. These theoretical results

may suggest new possibilities for the detection of heavy ions

and for the interpretation of some types of audio-frequency observations. --Author's abstract.

A-572 Hines, CO., Motions in the ionosphere. Institute of Radio

Engineers, N. Y. , Proceedings, 47(2): 176-186, Feb. 1959. 3

figs. , 70 refs. , 2 eqs. DLC--The ionosphere, even in its

"undisturbed" state, is constantly in motion. Its charged and

uncharged constituents may travel together or independently,

while irregularities in the distribution of charge may take a

different course again. The pertinent observational data are extensive and, in some cases, conflicting; their interpretation is seldom direct. The theoretical factors affecting that

interpretation are becoming clear, though in some cases their

areas of relevance are still subject to divergent opinions. An

attempt is made here to bring into focus the theoretical factors

themselves, to record their bearing on the observations wherever it has been established, and to suggest paths of future

progress wherever it has not. Details of observational results

and theoretical developments are largely suppressed, and with

them the conflicts and discrepancies which, however, real,

would obscure the presentation of the principles involved. -- Author's summary.

A-573 Hines, CO., An interpretation of certain ionospheric motions

in terms of atmospheric waves. Journal of Geophysical Research 64(12) :2210-2211, Dec. 1959. 5 refs. , 2 eqs.

A-574 Hines, CO. (Defence Res. Board, Ottawa, Canada), On

the rotation of the polar ionospheric regions. Journal of Geophysical Research, Wash., D.C, 65(1): 141-143, Jan. 1960.

2 refs. , 12 eqs. DWB, DLC--The possibility of magnetic coupling between the polar regions of the earth's ionosphere and the

interplanetary gas has led to the suggestion that the polar ionosphere may not rotate with the earth. The depth to which the

effects of the interplanetary drag might penetrate is examined

here with the aid of two simple models. The results are not

conclusive, but they do indicate that heights as low as the E

region may be involved. --Author's abstract.

A-575 Hoffman, William C , A theoretical model for high-frequency

backscatter from the sea surface via the ionosphere. Journal

of Atmospheric and Terrestrial Physics, London, 7(4/5) :278-

284, Oct. 1955. 2 figs. , table, 12 refs. , 14 eqs. DWB--

The sizeable backscatter from the ocean for high-frequency

radio waves propagated via the ionosphere is accounted for,

using an essentially realistic model of the sea surface. The
167

sea surface is in fact random; however, a good working approximation (at least in the case of high-frequency radio

waves) is a perfectly conducting doubly-trochoidal or doubly

sinusoidal surface. The average far-zone backscattered power is computed for each type of surface on the basis of the

"current distribution" method and Breit-Tuve theorem. The as- signment of realistic values to the ocean parameters then

yields values of the backscattered power which are of the

same order of magnitude as those observed. --Author's abstract.

A-576 Hoffman, W. C. , A possible mechanism for radiation and re - flection from ionized gas clouds . Institute of Radio Engineers,

Proceedings, 47(7): 1274-1275, July 1959. ref.

A-577 Hofmeyer, W. L. , A statistical analysis of radar winds over

Pretoria in winter. South Africa. Weather Bureau, Notos,

1(4):186-192, 1952. 4 figs. , 7 tables, 6 refs. DWB-Upper

winds obtained by radar at Pretoria have been statistically

analyzed for the winter 1952. The results indicate that these

winds are on the whole north-easterly near the surface and

that they frequently back through north to westerly at a fairly

low level in the free atmosphere. Average velocities vary

from approximately 10 knots near the surface to a maximum of

the order of 60 knots at about 200 mb. Above this level, velocities decrease rapidly and directions deviate from mainly

westerly at 200 mb to practically all points of the compass at

60 mb. Other statistical results are in respect of standard

deviations, frequency distributions and correlation coefficients of the west to east and south to north components and,

in certain cases, of the resultant vectors. --Author's abstract.

A-578 Hok, Gunnar; Spencer, N. W. and Dow, W. G. (Dept. of Elec.

Engr. , Michigan Univ. , Ann Arbor), Dynamic probe measure- ments in the ionosphere. Journal of Geophysical Research,

58(2): 235-242, June 1953. 6 figs., 3 refs. Also in: Michigan

Univ. , Engineering Research Institute, Contract W-33-038-ac14050, Project M824, Upper Air Research Program, Report No.

3, Nov. 1951. MH-BH, DWB--Preliminary rather successful

attempts to determine the ionization in the E-layer by means

of a probe technique are described. The probe current showed

an extremely rapid rise between 90 and 105 km altitude. The

result indicates a positive-ion density about ten times larger

than the electron density. Further measurements with improved

equipment are recommended. --Authors' abstract.
168

A-579 Hok, Gunnar and Dow, W. G. (Electrical Eng. Dept. , Michigan Univ. ) f Exploration of the ionosphere by means of a Lang- muir-probe technique . (In: Boyd, R.L.F. , Seaton, M.J. and

Massey, H. S. W. (eds. ), Rocket exploration of the upper atmosphere. London, Pergamon, 1954. p. 240-246. 6 figs. , 5

refs. ) DWB--Irving Langmuir and his team developed in 1920

a method of measuring the concentration and energies of ions

and electrons in electrical discharges in gases. A cylindrical probe was used to observe the positive ions in the current.

Today, high-flying rockets have carried the probes into the

ionosphere where ion electron plasma exists. From White

Sands Proving Grounds in New Mexico, reducible data were

obtained on Dec. 8, 1947 at an altitude a little more than 60

km. The evidence of the positive ion current continued to increase with the altitude. The results of the probes have been

remarkable. The rockets have reached a maximum altitude of

104 km at a time when the height of E-layer was 110 km. --N. N.

A-580 Hok, Gunnar; Sic inski, H. S. and Spencer, N. W. (all, Dept.

of Elec. Engr. , Univ. of Michigan), Temperature and electron

density measurements in the ionosphere by a Langmuir probe.

(In: Van Allen, James A. (ed. ), Scientific uses of earth satellites. Ann Arbor, Univ. of Michigan Press, 1956. p. 263-

267. fig., 4 refs.) DWB--Langmuir probe techniques offer interesting possibilities for obtaining important data by measurements from an ionospheric satellite. The feasibility of such

measurements has been demonstrated in a preliminary manner

on rockets in the lower E-layer of the ionosphere. The most

straightforward data calculated from probe records are for temperature. Approximate thermal equilibrium is assumed in each

stratum of the ionosphere. During part of each voltage sweep

predominantly electrons are collected; this electron current

yields both temperature and electron density. The collection

of positive ions appears difficult to translate into useful information. --Authors' abstract.

A-581 Holt, Olav and Landmark Bjjrfrn (both, Norwegian Defence Res.

Establishment, Kjeller), Some statistical properties of the sig- nal fine structure in ionospheric scatter propagation. Geofysiske Publikasjoner, Oslo, 20(8), March 1958. 7 p. 7 figs.,

7 refs. , eqs. DLC, DWB--Some statistical properties of the

signal fine structure for a VHF ionospheric scatter circuit between northern and southern Norway have been examined. It is shown that the background component of the signal has statistical properties in agreement with those to be expected for

Gaussian noise, and that this signal therefore can be explained in terms of scattering from a large number of irregularities.

The fading of the enduring meteoric bursts, on the other hand,

must be explained in terms of interference between a few
169

reflected components resulting from bending of the trail due

to large scale wind gradients. --Authors' abstract.

A-582 Hopkins, H. G. and Reynolds, L. G. , An experimental investigation of short -distance ionospheric propagation at low and

very low frequencies . Institution of Electrical Engineers, Pt.

3, 101(69): 21 -34, Jan. 1954. 10 figs. , 13 tables, 19 refs.

DWB--The properties of the lower portion of the ionosphere

have been studied at selected low and very low frequencies

by observations of commercial continuous -wave transmitters

located at distances of about 100 km from the receiving point.

Attention has, in general, been confined to the horizontallypolarized electric component of the ionospheric wave received

by means of a vertical loop set normal to the plane of propagation. Using mainly twin-channel recording equipment, an outline description of which is given, the pick-up on this loop

has been compared in phase and magnitude with that on another vertical loop arranged in the plane of propagation. Changes

in the apparent height and conversion coefficient of the reflecting layer have been studied, mainly at 16 and 70. 8 kc/s, in

terms of a simple model under both normal and disturbed conditions. The data serve generally to the measurements of other

observers, but some discrepancies are discussed. It is considered that pulse -sounding technique has advantages over the

continuous -wave method for ionospheric measurements in the

frequency band under review, particularly at the higher frequencies. --Authors' abstract.

A-583 Hormuth, W. , Statistik der Schwundabhangigen Gerauschlei- stung fur Breitband-Richtfunkverbindungen mit vielen Funkfeld - ern. (Statistics on the fading-dependent noise yield of centimeter directional radio communications with several radio

fields.) Archiv der Elektrische Ubertragung, 12(8): 346-356,

Aug. 1958. 7 figs., 8 refs.

A-584 Horner, F. , Measurements of atmospheric noise at high frequencies during the years 1945-1951. Great Britain. Dept. of

Scientific and Industrial Research, Radio Research, Special

Report, No. 26, 1953. 40 p. numerous figs. , 8 tables. DWB

-•Results of measurements at 20 noise measuring stations in

all parts of the world are analyzed for period 1945-51. Year

to year, seasonal and diurnal variations as well as geographical differences are revealed in graphs and text. Various frequencies (2.5, 5, 10, 15 and 20 mc/s) are considered. Changes

in methods of prediction for 2. 5 and 5 mc/s are indicated as a result of this survey. No changes in 15 and 25 mc range seems

necessary. This is thought to be due to the fact that higher

frequency noise comes from distant thunderstorms and lower

frequencies from more critical local thunderstorm areas. --M. R.
170

A-585 Horner, F. and Harwood, J. , An investigation of atmospheric

radio noise at very low frequencies. Institution of Electrical

Engineers, Proceedings, Pt. B, 103(12): 743-751, Nov. 1956.

11 figs. , 8 refs. , 9 eqs. DLC --Technical aspects of noise

measurements for long wave reception; nature of noise; aver- age probability and amplitude distribution of voltage peaks;

time distribution of peaks; measuring equipment; pen records,

diurnal and seasonal variations in field strength, noise structure, amplitude probability, distribution of envelope and time

distribution of major impulses are analyzed and discussed.

Examples are cited and illustrated by records and curves for

varying situations of thunderstorm incidence during July-Sept.

,

1955 in southern England (Radio Research Station). --M. R.

A-586 Horner, F. , La relation entre la propagation des ondes tres

longues et la direction. (Relation between the propagation of

very long waves and their direction. ) L'Onde Electrique, Paris,

37(362): 535-538, May 1957. fig., 2 tables, 7 refs. DLC--

Measurements made in England on 16 kc near vertical incidence show that about half the incident power is reflected from

the ionosphere at night, the reflected signal being polarized

elliptically toward the left. Results obtained in August over

two short paths in different directions are in agreement with

the hypothesis that the long axis of the ellipse of electrical

polarization forms a 70 angle to the magnetic north, the eccentricity being 0. 55. These results are similar to those published earlier for frequencies of the order of 100 Kc. --Trans,

of author's abstract.

A-587 Horner, F. (Radio Res. Station, Slough, Eng. ), Polarization

of atmospherics. Nature, London, 181 -(4624): 1678-1679, June

14, 1958. 2 figs. DWB--A complex type of trace was obtained with a twin-channel cathode-ray direction finder. This paper

contains assumptions and deductions on the polarization of the

echoes that were received after varying numbers of reflections

between earth and ionosphere. It is concluded that the trace

can be produced by a vertical discharge to the ground, and not

by a horizontal discharge channel. --N. N.

A-588 Hosking, R.H. (Dep. of Physics, Queensland Univ. , Brisbane), The mean thickness of night-time Es clouds at Brisbane . Australian Journal of Physics, Melbourne, 19(1): 220-221, March

1957. 3 refs. DLC --Measurements of thickness of Es (sporadic E clouds) at night by measuring (a) the equivalent paths of

echoes from their under surfaces and from the F region, and

from internal reflection between the F region and the top of the

Esc before returning to the ground, at 2. 28 Mc/s at Brisbane

for range 0-500 km during 1952, 1953 and 1954 were analyzed

and the mean of 98 measurements gave a thickness of 0. 33 km

with a standard error of 0. 23 km. --M. R.
171

A-589 Houston, Robert E. , Jr. , 75 Kc/s in phase height instrumen- tation and data. Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF 19(604) -1304, Scientific Report, No.

93, May 1, 1957. 68 p. 34 figs., table, 14 refs. DWB(M10.

535 P415i)--The instrumentation utilized in measuring changes

in phase of a pulsed radio signal, whose carrier frequency is

75 kc/s and is vertically incident on the lower ionosphere, is

described. The various components in the equipment are discussed in some detail. Block and schematic diagrams and

photographs are included. It is pointed out that the entire

apparatus acts as a radio interferometer and recorder. Illustrations of the various types of records obtained are shown,

and the method of reduc ing them to monthly averages is indicated. Where enough daily records were available, the monthly average of the change in phase height of the main E layer reflection is given. It is concluded that the operation of

the equipment is satisfactory. The received signals are phase

stable and resolved sufficiently to be measured. A recommendation for the study of anomalous events in the ionosphere is

made. --Author's abstract.

A-590 Howe, G. W. O. , Radio waves and the ionosphere . Institution of Radio Engineers, Journal, 7(l):36-42, Jan. -Feb. 1947.

5 figs., eqs. DBS--In this historical survey is shown what

happens to a radio wave during its passage through the ionosphere as a dispersive medium, like a glass prism. --W. N.

A-591 Howells, I. D. (Cavendish Lab. , Cambridge, Eng. ), On the

spectrum of electron density produced by turbulence in the

ionosphere in the presence of a magnetic field . Journal of Geophysical Research, Wash., D.C., 64(12): 2198-2199, Dec.

1959. ref. , 5 eqs. DLC--The work described in this paper

starts from Dungay's results, and obtains approximate equations for number density of ionization, under the action of

turbulence, diffusion, and a magnetic field, in various limiting cases. The principal result is that this mechanism cannot be expected to produce irregularities that are strongly elongated along the magnetic field. A form is obtained for the

spectrum function of number density below 140 km.

A-592 Hugenholtz, E.H. ; Seljak, A. and Towle, A., Frequency

stepper for radio propagation tests . Electronics, 32(4) :44-

46, Jan. 23, 1959. --Schematic and descriptive details are given.

A-593 Hultqvist, Bengt, On the interpretation of ionization in the

lower ionosphere occurring on both day and night side of the

earth within a few hours after some solar flares. Tellus, 11(3):

332-343, Aug. 1959. 9 figs. , 3 tables, 23 refs. , 6 eqs.
172

A-594 Hultqvist, Bengt and Ortner, Johannes (both, Kiruna Geophys.

Observ. , Kiruna C. , Sweden), Strongly absorbing layers below 50 km. Planetary and Space Science, N. Y. , l(3):193-204,

Aug. 1959. 8 figs., table, 34 refs., 8 eqs. DWB--In a few

cases of very strong absorption of very long duration observed

at Kiruna Geophysical Observatory during the summer of 1958,

the height of the upper boundary of the ionized layer has been

found to be about 50 km. It is shown that this height value

accords well with what is to be expected if the ionizing agent

consists of protons. Earlier proposed interpretation is discussed with regard to this new height information. --Authors'

abstract.

A-595 Humby, A. M. ; Minnis, CM. and Hitchcock, R.J. , Performance characteristics of high-frequency radio-telegraph circuits . Institution of Electrical Engineers, London, Proceedings, Ser.

B, 102(4): 513-522, July 1955. 21 figs. , table, 8 refs. DWB

--Operational data from several important long-distance radiotelegraph circuits have been analyzed and the results discussed in relation to variations in solar and magnetic activity.

It is shown that the lowest operational efficiency on radio circuits need not necessarily occur at the same time as the lowest level of solar activity. For example, in 1952 the performance of many difficult radio circuits deteriorated considerably,

coincident with a peak of magnetic activity, but subsequently

recovered although solar activity continued to fall. On certain

circuits there is a pronounced seasonal asymmetry of performance in the two directions of the route; to confirm that this

is due to propagation effects, data from different organizations

operating on substantially the same radio path are compared—

particular reference being made to the United Kingdom-South

Africa and the United Kingdom-Australia circuits. Suggestions

are put forward as to the possible reasons for this asymmetry

with season, and consideration is given to effects such as ionospheric propagation, atmospheric noise and the path taken by

the ray. Mention is also made of other propagation phenomena,

such as echo signals, maximum latitude of ray path and M re- flections, which have a bearing on the operation of radiotelegraph circuits. For the purposes of the paper all references to

seasons relate to the Northern Hemisphere. --Authors' abstract.

A-596 Huxley, L. G.H. and Ratcliffe, J. A. , A survey of ionospheric

cross -modulation. Institution of Electrical Engineers, Proceedings, Pt. 3, 96(43) :433-440, Sept. 1949. 3 figs., table, 24

refs. , 17 eqs. DLC --History, detailed theory and results of

recent experiments on cross -modulation in ionospheric research.

Theories of Bailey and Martyn revised. Magnitude of cross- modulation effect can be calculated for any pair of stations.

Methods of observation described. --M. R.
173

A-597 Huxley, L.G.H. (Adelaide Univ. , S. Australia), A synopsis of ionospheric cross modulation. U. S. Air Force. Cambridge Research Center, Geophysical Research Papers, No.

11:137-170, 1952. figs., tables, 23 refs. DWB. Also in:

Nuovo Cimento, Ser. 9, 9(1), Suppl. p. 59-82, 1952. 6 figs.

,

2 tables, 22 refs., 41 eqs. DLC --Ionospheric cross modulation (radio wave interaction) observations made at Cambridge

and Birmingham show agreement with theory of MARTYN and

BAILEY based on knowledge of chaotic motion of free electrons

in gases and electric fields. The theory is developed in detail,

the experimental set up described and illustrated, and the seat

of cross modulation located at 85 to 90 km, with a scale height

of about 8. 5 km for V at 90 km. Pressure deduced from these

data agree with rocket data for 90 km height. A formula for

power supplied per electron from the disturbing wave, generalized to include oblique incidence, gives values to To close to

those observed in nature (neglecting influence of earth's magnetic field). --M. R.

A-598 Huxley, L.G.H., The interpretation of measurements of radiowave interaction. Journal of Atmospheric and Terrestrial Physics, London, 8(1/2): 118-120, Feb. 1956. 7 refs. , 6 eqs.

DWB--The original theory of interaction of radio waves is modified to take account of the molecular concentration instead of

the collisional frequency. --C. E. P. B.

A-599 Inoue, Yuji (Technical Research Inst. , National Defense

Agency, Tokyo, Japan), On the ionization mechanism in the

ionosphere. Japanese Journal of Geophysics, Tokyo, 1(3):

21-120, March 1957. 8 figs. , 21 tables, 71 refs. , 141 eqs.

DWB--The theories proposed so far on the formation of the ionosphere are criticized. In particular, those on the formation

of the E layer are inspected and discussed. The arguments of

criticism are based on rocket measurement data, variations of

the ionosphere during solar eclipses, results of recent resear- ches in solar physics, and experimental data about rates of

various reactions. It is shown that all the formation theories

put forward so far are incomplete. In this paper, a new interpretation of the effective recombination coefficients of an electron in the ionosphere is developed. A new theory for the

ionization mechanism in the ionosphere is also brought forward. With respect to the dissipation of electrons it is suggested that an electron is attached to molecular oxygen located at a vibrationally excited level; as a result, a stable negative ion of molecular oxygen is formed; subsequently, a mutual

neutralization between this negative ion and a positive ion becomes effective. Attachment processes of a slow electron to

molecular oxygen are discussed. A favorable process for

stabilization is found. The principal part of positive ion -
174

concentrations is of atomic oxygen; the concentration of positive ions of molecular nitrogen is negligible. When a mutual

neutralization between a negative ion of molecular oxygen and

a positive ion of atomic oxygen takes place, the resulting atomic oxygen is almost all in a highly excited state whose en- ergy is more than 9. lleV as compared with its ground state.

This atomic oxygen gives rise to the emission of photon of its

resonance lines as a result of the spontaneous transition from

its highly excited state to the ground state. The resonance

lines of atomic oxygen are of 1302-1306 A (01, 3s3S° -2p3P)

and 1025. 7 A (01, 3d3D° -2p3P). These lines were observed

at 115 km as an emission line by the rocket-borne spectrograph of U. S. Naval Research Laboratory. It appears that

these lines are "ionospheric" and "non-solar". The photons of

the resonance lines, which appear as a result of the ionospheric recombination, are absorbed by oxygen atoms and the

oxygen atoms in the highly excited states are resulted, from

which they are ionized with the aid of a visible radiation, being in abundance. The photons of the resonance lines permeate in a scattered radiation down into the E layer, and then

they are richly stored up in the E region. The ionization in

the E layer is that from the highly excited states of atomic

oxygen due to a visible radiation. Such an ionization mechanism explains the variation of the E layer during solar eclipses. With respect to the permeation of the resonance radiations of atomic oxygen, the effects of molecular absorption in

the ionosphere are discussed. It is concluded that the incident ionizing radiations come from the chromosphere as well

as the corona. --Author's abstract.

A-600 International Council of Scientific Unions. Joint Commission

on Radio-Meteorology, Brussels, Aug. 16-18, 1954. Proceedings of the 3rd meeting, pub. 1955. 30 p. t-p. in French and

English. Text in French or English. DWB--On p. 18-26 the

work of WMO in the field of sferics research is summed up

(in French). A report is included on a special meeting held

in Zurich in May 1954 by sferics experts delegated by the governments of the United Kingdom, France and Switzerland. Discussions and resolutions of this meeting concerning various

applications of sferics observations, comparison of different

instruments and methods, international coordination, etc. , are summed up. Reference is also made to the most important

sources of information on sferics. --G. T.

A-601 International Council of Scientific Unions. Mixed Commission

on the Ionosphere, 2nd Meeting, Brussels, Sept. 1950 Proceedings. Brussels, Pub. by the Council, 1951. 230 p. figs.,

tables, refs. , eqs. DWB--
175

The Mixed Commission on the Ionosphere consists of members

from the International Scientific Radio Union, the I. U. G. G.

,

the International Astronomical Union and the International

Union of Pure and Applied Physics. Over 30 papers on the

ionosphere, aurora and upper atmospheric investigations and

theory which were read at the 1950 meeting in connection with

the meeting of the I. U. G. G. in Brussels, are presented in

English, with illustrative material included. Minutes of the

sessions of the 4th and 6th of Sept. 1950, names of members,

those attending, and discussions of papers. Commission re- solutions and a proposal for an International Polar Year (1957/

8) are included. Each paper has been abstracted separately

and many are included in this bibliography. --M. R.

A-602 International Council of Scientific Unions. Mixed Commission

on the Ionosphere. N. Y. Univ. , Aug. 14-16, 1957. Proceedings of the fifth meeting. Ed. by W. J. G. Beynon. Journal of

Atmospheric and Terrestrial Physics, London, 15(1):1-176,

Sept. 1959. --The Fifth Meeting of the Mixed Commission on

the Ionosphere of I. C. S. U. was held at New York University,

Aug. 14-16, 1959. The present issue consists of two parts,

viz: 1. Proceedings of the meeting as follows: Session I - Sir

Edward Appleton: Global morphology of the E- and F-l layers

of the ionosphere. W. J. G. Beynon: Vertical drift effects in

region E. Session II - J. A. Ratcliffe, A. R. Robbins and J. O.

Thomas: Movements in the quiet F-layer over Slough. Session

III - P. Lejay: Irregularites ionospheriques. S. Chapman: Disturbances in the lower auroral ionosphere. K. Rawer: Irregularities and movements in the F-region. Sessions IV and V - S. Chapman: The outermost ionosphere. S. F. Singer: Geophysical effects of solar corpuscular radiation. J.L.Pawsey: The

question of radio emission by the ionosphere. M.G.Morgan:

Whistlers. K. Maeda and I. Kimura: Calculation of the propagation path of whistling atmospherics. Session VI - Resolutions. Part 2 includes the following 26 papers submitted to

the Commission. S. Matsushita: The morphology of the lower

ionospheric region in auroral latitudes. J. M. Watts: Interpretation of some features of low-frequency ionograms. I. Shimazaki: Effect of the Sq current system on the ionospheric E- and

Fl- layers. A. Haubert: Les gradients de temperature dans

les regions-E et -Fl, d'apres les sondages ionospheriques effectues a Casablanca. A. Haubert: L'ionisation nocturne de

la region-E et l'activite geomagnetique. Y. Inoue: On the importance of the resonance-lines of atomic oxygen to the ionospheric ionization. T. Yonezawa: A new theory of formation of

the F2 layer. J. W. Chamberlain: Excitation of the oxygen red

lines in twilight. J. W. Chamberlain: Recombination in the F2

layer and the oxygen red lines in the airglow. G. J. Gassmann:

Tides in the F-layer. A. R. Robbins and J. O. Thomas: The
176

disturbed F-layer over Slough. T. Shimazaki: Dynamical structure of the ionospheric F2-layer as deduced from the worldwide daily variations. T.Sato: Ionospheric F 2-disturbances

associated with geomagnetic storms. R. W. Wright and N. J. Skinner: Equatorial spread-F. I. Kasuya: On the occurrence of

the Fl^ -layer at Tokyo. M.Ose, K. Aida and H. Okam^to:

Latitude dependence of £qF2 over the range of 20 N to 69 S,

obtained by ship-borne ionospheric sounder. W. G. Elford:

Winds in the upper atmosphere. L. A. Manning: Air motions

at meteoric heights. K. Rawer: Drift in the E-region. A. Haubert: A propos des grands mouvements verticaux de la regionF. M.Hirono, H. Maeda and S. Kato: Wind systems and

drift motions in the ionosphere deduced from the dynamo theory. K. Sinno: On the origin of the long-lived solar corpuscular streams which appeared during the last solar cycle,

1950-53. S. Akasofu: Magneto-hydrodynamic waves in the

ionosphere. W. Pfister and J. C. Ulwick: Analysis of pulsedelay data from rockets for the determination of electron density. W. J. G. Beynon and G. M. Brown: Region E and solar activity. L. Vegard: Report on spectrographic work at Troms^

and Oslo. The list of membership of the Mixed Commission

on the Ionosphere is followed by the names of representatives

participating at the New York meeting. The alphabetical

author index also serves to denote participation in the discussion of the papers presented. --W.N.

A-603 International Geophysical Year, 1957/1958. Comite Special,

Meeting of the Special Committee of the International Geophysical Year. Rome. Sept. 30-Oct. 4. 1954. 12 sections, each

separately paged. Mimeo. DLC --Includes reports of the following groups: 1. World days, 2. Meteorology, 3. Geomagnetism, 4. Airglow and aurora, 5. Ionosphere, 6. Solar activity,

7. Cosmic rays, 8. Latitudes and longitudes, 9. Glaciology,

10. Oceanography and 11. Rockets. A complete list of attendants, transactions of the assembly of CSAGI at Rome from

Sept. 30-Oct. 4, 1954, including resolutions and recommendations, lists of stations, program of work, etc. for each of the

11 sub-committees named above plus work of the 12th and 13th

sub-committees (Geophysical distribution and Publications and

publicity) and names of chairman and members of the 13 committees. The activities of the President (S. Chapman), Vice

President (L. V. Berkner) and Secretary General (M.Nicolet) in

1953 and 1954 are reported. --M. R.

A-604 International Geophysical Year, 1957/1958. Comite Special

(CSAGI), Second Meeting. Rome. Sept. 30-Oct. 4. 1954

(Proceedings, continued). Its Bulletin d' Information, No. 5,

1955. 79 p. tables. DWB. Preprint from International Union

of Geodesy and Geophysics, IUGG Bulletin d' Information, News

Letter, No. 11, 1955. --
177

This report lists stations in all parts of the globe, with geographical and magnetic coordinates, proposed for IGY, 1957/

58, under headings of Meteorology (including ozone, radiation and spherics stations), Geomagnetism, Aurora and Airglow, Ionosphere, Solar activity, Cosmic ray. Latitude and

longitude, Glaciology, Oceanography, Rockets and according to Arctic, Antarctic, Equational, 80° - 70°W, 10°E and

140 E longitude lines. In all, several thousand stations are

listed. -M. R.

A-605 The International Geophysical Year: Indian Programme. Journal

of Scientific and Industrial Research, Sec. A, 16(6):231-233,

June 1957. DWB, DLC--A score of governmental, semigovernmental and private institutions and universities in India are

listed as cooperating in the IGY effort, as well as the meteorological and magnetic network of the Indian Meteorological

Department. The special program in meteorology, geomagnetism, aurora and airglow, ionosphere, solar activity, cosmic

rays, glaciology, oceanography, satellite tracking, seismology and gravity is outlined. In meteorology, 10 stations will

make upper air soundings, 4 will conduct ozone measurements,

4 radiation and thermal balance measurements, 2 radar storm

tracking (long range), and 2 or 3 local storm studies with ra- dar. Two will measure the electrical potential gradient, 2

sferics, 12 evaporation and 8 auroral observations. --M. R.

A-606 International Geophysical Year, 1957/1958. U.S. National

Committee, Antarctic program. National Academy of Sciences— National Research Council, Publication, No. 553,

Sept. 1957. 58 p. 17 plates, photos, 13 tables. DWB--

This monograph gives a list (and map) of U. S. IGY stations

in the Antarctic, a summary of activities in 10 fields, plus

special studies undertaken. A summarization of scientific

and support personnel in each discipline and of each type at

each station, station facilities and equipment, communications by land, sea, air and radio, time table of operations

for 1954-5, 1955-6, 1956-7 and 1957-8, etc. is included.

Station layouts at 7 places, buildings, site plans and photographs of stations and facilities are shown graphically. --M. R.

A-607 International Scientific Radio Union. Mixed Commission of

the Ionosphere. Reunion de Bruxelles du 28 au 30 julliet 1948. Brussels Meeting 28th to 30th July 1948. International Scientific Radio Union, Bulletin Mensuel, No. 50:18-20, Aug. 1948.

DLC--The subjects for discussion with introductory speaker at

the successive meetings were: 1) knowledge of the ionosphere

by radio sounding methods (APPLETON); 2) knowledge of the

ionosphere from studies of auroras (VEGARD); 3) atomic processes in the ionosphere (NICOLET); 4) solar knowledge
178

relevant to the ionosphere (WOOLEY) and correlation of ionospheric with astrophysical phenomena (STRATTON); 5) knowledge of the ionosphere from studies of geomagnetism (CHAPMAM) and 6) general discussion on the work of the Commission. List of previous attendings and resolutions drawn up

by the Commission are included. --M. R.

A-608 International Scientific Radio Union. Proceedings of the 11th

Assembly. The Hague, Aug. 23-Sept. 2. 1954, Vol. 10, Pt . 4, Commission 4 on Radio Noise of Terrestrial Origin, pub.

1955. 60 p. refs. DWB--In addition to minutes of the several sessions, a number of reports concerning observations

of sferics in Australia, Canada, France, Germany, Great

Britain, Japan, Sweden, Switzerland and the U. S. A. by chairmen of the National Committee of those countries (including

A. EHMERT, F HORNER, A. KIMPARA, H. NORINDER, J. LUGEON and H. DICKSON) are included in these Proceedings.

Reference to numerous papers on atmospherics, including meteorological aspects as well as recording and radio aspects,

are presented by most countries. Resolutions with respect

to preparation of revised sferics charts, study of wave forms,

IGY program etc. are appended.-- M. R.

A-609 International Scientific Radio Union, Information Bulletin,

Brussels, No. 92, July/Aug. 1955. 27 p. 3 figs. , refs.

DWB--Reports on membership of National Committee of India

and U. S. A. , a bibliography on effects of solar eclipses on

the ionosphere, on the recording of sudden enhancements of

sferics and on radio astronomy in Belgium, etc. --M. R.

A-610 International Scientific Radio Union, Information Bulletin,

Brussels, No. 93, Sept. /Oct. 1955. 45 p. 11 figs. , Stables, refs. , 17 eqs. DWB--Reports on 11th General Assembly

by National Committee of India and Japan on symposis on ionospheric drifts and on ionospheric storms, respectively, on

ionospheric stations, ursigrams, IGY (Resolution of WMO re- specting a center for observational data, bibliography and

documentation for IGY and standard forms for surface and upper air data), etc. --M. R.

A-611 Ionescu, T. V. , Sur la diffusion des ondes electriques de

tres grande frequence dans 1' ionosphere. (Ionospheric scattering of very high frequency electric waves.) Academie des

Sciences, Paris, Comptes Rendus, 245(5): 520-522, July 29,

1957. 3 refs. DLC--The author points out that the diffusion

of very high frequency electric waves can be explained through

the negative molecular oxygen ions, which possess their own

vibration periods and are produced in great number at altitudes
179

from 50 to 90 km. This theory concerning diffusion of electric waves in the ionosphere makes it possible to calculate

the diffused power value. --A. V.

A-612 Israel, H. and Kasemir, H. W. , In welcher Hoehe geht der

weltweite luftelektrische Ausqleich vor sich? (At what height does atmospheric electric equilibrium take place?) Annates de Geophysique, 5(4):313-324, Oct. -Dec. 1949. 3 figs. , 2 tables, 13 refs. , 23 eqs. French and German summaries.

MH-BH--Integration of the partial derivatives to find the time

that would be required for a charge introduced at a point in a conductive layer sandwiched between two nonconductive lay- ers to be uniformly distributed throughout the former layer.

This theory and calculation is applied to the ionospheric lay- ers over the globe. --M. R.

A-613 Isted, G. A. , Atmospheric electricity and long distance very

high frequency scatter transmission. Marconi Review, London, 17(113) :37-60, 2nd quarter, 1954. 10 figs., 15 refs.

DLC --During an investigation into the behavior of long distance transmissions on very high radio frequencies a new phenomenon has been encountered which has a direct relation to

electrical discharges from ordinary clouds in the lower atmosphere. Signals radiated in the 30-100 Mc/s band and transmitted to distances of 500 km and more, arrive at the receiver

in a succession of impulsive bursts. A theory has been evolved to show how electrical discharges from clouds can form

pockets of intense ionization in the E region; furthermore, the

theory suggests that ordinary clouds, distinct from thunderstorm clouds, may be the chief electrical generators which

maintain the fine weather vertical potential gradient. It is

also suggested that when energy is transferred from discharging clouds to fine weather areas, continuous partial ionization of the E region conduction path is set up and in extreme

cases may result in the formation of sporadic E. --From author's abstract.

614 Isted, G.A. , Round-the-world echoes. Marconi Review,

London, 21(131):173-183, 1958. 4 figs. , 13 refs. DLC--

Observations made during an investigation into ionospheric

scatter propagation at a frequency of 37 Mc/s have shown

that round-the-world echoes were present along a south-north

route even when both the transmitting and receiving terminals

were well inside the daylight hemisphere. Under the conditions of the experiment the signal seemed to have been propagated through areas where, in the normally accepted sense,

the F2 region could not have been the supporting mechanism.

Round-the-world echoes have also been observed from the signals radiated at 20 Mc/s by Satellite 1957 Alpha. Analysis
180

of the records revealed the existence of two distinctly different beat notes, one from the square-wave signals themselves, the other occurring during the intervals between them.

The suggestion is put forward that transmission round the

world is made possible by launching a radio wave against the

ionosphere at an extremely small angle of incidence to produce a succession of reflections which are confined to the

ionosphere itself. --From author's abstract.

A-615 Isted, G. A. , Analysis of Gibraltar-United Kingdom ionosph- eric scatter signal recordings. Institution of Electrical Engineers, Proceedings, Pt. B. , Vol. 105, Suppl. ho. 8:36-44,

73-74, 77, 1958. table, 3 refs.

A-616 Istomin, V. G. , Issledovaniia ionnogo sostava atmosfery

Zemli na raketakh i sputnikakh. (Investigations of the ion

composition of the earth's atmosphere by rockets and satellites. ) Iskusstvennye Sputniki Zemli, Moscow, ISio. 2:32-

35, 1958. fig. , 3 refs. DLC--The construction and use of

the 5. 7 cycle variant of the radio frequency mass spectrograph of Bennet for measuring the ionic composition of the

atmosphere are described. Its range is 6-50 atomic units of

mass; the time of measurement for this range is 1. 7 sec. The

resolution in the region of mass number M = 28 is equal to

R = ^W-^Z^whereA M - width of the peak measured at

its base in atomic units of mass. The tube can be taken apart and is of metal glass construction. The radio frequency

analyzer is joined to the ionic source by means of vacuum

condensation to a copper gasket. The calibration characteristics were made on the basis of five points on the mass scale.

^40f a36, h>%8, Ne22 and N e20. The first vertical ascent

was made wifn a rocket in Sept. 1957, and the results are presented in a graph. The results showed that ions with mass

number 20 predominated at 105-206 km. Ions with other mass

numbers were present at 105-190 km in an amount not exceeding 20% of the maximum concentrations of ions with mass number 30. Ions with mass number 16 (atomic oxygen) were re- corded only from 192-206 km. The results of measurements

carried out with the third artificial earth satellite indicated

the following, viz: ions with mass number 16 (0+) predominated at heights above 250 km; these ions were recorded between 230 and 885 km. The second constituent was ions of

mass number 14 (N+). In addition to the peaks corresponding

to + and N there were obtained peaks corresponding to ions

of mass 18 (H2

+ ). --I.L.D.
181

A-617 Iwai, Akira and Outsu, Jinsuke, On an investigation of whistling atmospherics in Japan. Nagoya. Univ. Research In- stitute of Atmospherics, Proceedings, 4:29-47, Dec. 1956.

17 figs. , 3 tables, 9 refs. , eqs. DWB--As part of the Study

Program of IGY, we have prepared an observation of whistling atmospherics. Since Jan. 1956, continuous observations

of whistlers have been made at Toyokawa (geomag. lat. 24. 5 ). Simultaneous observations at Toyokawa and Wakkanai (geomag. lat. 35. 3 ) were made for one month beginning July 13,

1956. The results obtained in the analysis of the dispersion

of whistlers were essentially similar to those reported by

STOREY. But, at Toyokawa, long whistlers, whistler trains

and whistler pairs have not been observed, only short whistlers being observed. The greater part of the observed whistlers occurred in winter; in other seasons it was scarcely possible to detect them. At Wakkanai, long whistlers and whistler pairs have been observed this summer, but whistler trains

have not been observed during this period. --Authors' abstract.

A-618 Iwai, Akira and Outsu, Jinsuke, On the characteristic phen- omena for short whistlers observed at Toyokawa in winter. Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 5:53-63, March 1958. 7 figs. , 2 refs. , 6 eqs. DWB--

About 84% of short whistlers observed at Toyokawa on winter

nights were recognized by analysis to be preceded by tweek

type atmospherics, which made it possible to measure distances between the observation station and the sources of

short whistlers. And at Toyokawa in winter, dispersions of

short whistlers were found to decrease regularly towards midnight. A variation of electron density in the outer ionosphere

is calculated from this variation of dispersions. --Authors' abstract.

A-619 Iwai, Akira and Outsu, Jinsuke, On an investigation of the

field intensity of whistling atmospherics. Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 5:50-52, March

1958. 5 figs. , 4 tables. DWB--An apparatus is described

and its wiring illustrated (diagrammatically), for creating a pseudo-whistling tone to compare with an actual whistler in

order to gage the field intensity of the latter. The full intensity is calibrated in microvolts/meter and the record can be

obtained in 1-2 sec by a skillful operator. A "sona gram" of

the pseudo-whistling tone generator is illustrated and a typical example of data obtained at Toyokawa on Feb. 12, 1957

tabulated (an unusually frequent series of whistlers). These

occurred about sunset on several days in Feb. 1957. It is

concluded that the frequency and full intensity of whistlers

varies greatly with geomagnetic latitude, etc. --M. R.
132

A-620 Jacchia, Luigi G. (Astrophysical Obs. , Smithsonian Inst. ) # Basic orbital data for satellite 1957 Beta one . Smithsonian

Institution. Astrophysical Observatory, IGY Project No.

30.10, Special Report, No. 9, Feb. 21, 1958. 7 p. fig.,

3 tables, 3 refs. Also issued in "edited form" as Smithsonian Contributions to Astrophysics, Wash., D.C., 2(10):285-

236. DWB, DLC--Results of 1100 optical and radio observations of satellite 1957 Beta one during Nov.,, Dec. 1957 and

Jan. and Feb. (to Feb. 10O 1958 are tabulated and discussed.

--M.R.

A-621 Jackson, Howard J. ; Smith, Harold D. , and Post, Cecil C. , Performance of the 580-S00 megacycle slot antenna for the

aerobee rocket. New Mexico. College of Agriculture and

Mechanic Arts. Physical Science Laboratory, Contract AF

19(604)-409, Scientific Report iso. 3, Feb. 7, 1956. 16 p.

13 figs. (incl. photos.), ref. --Antenna pattern measurements

for the 580-600 Mc/sec 3-slot array antenna were made on a section of the Aerobee rocket. Measurements were made in

the principal planes through the center of each slot. Measurements of the transmission loss and phase characteristics

of the 3-slot array antenna feed harness were made. Transmission loss was found to be 0. 5 db + 0. 2 db per section,

and the relative phase difference at the output of each section was found to be not greater than +2 degrees. Voltage

standing wave ratio measurements were taken on each slot

and its associated feed harness, as well as on the complete

3-slot array. --Authors' abstract.

A-622 Jackson, John E. (N aval Res. Lab., Wash., D. C. ), Rocket

borne instrumentation for ionosphere propagation experiments.

U. S. Naval Research Laboratory, Upper Atmosphere Research

Report, No. 13, Jan. 9, 1952. 39 p. 22+ figs., table, 15

eqs. U. S. K aval Research Laboratory, Report 3909. DWB

--The rocket-borne equipment used for the ionosphere propagation experiments conducted during V-2 and Viking flights has

been developed and improved to the extent that satisfactory

operation has been obtained in all recent flights. Various

problems were encountered in the development owing to the

limitations imposed by the research vehicle and the method

of experimentation. Space and weight, as well as freedom

from interference with other cooperating agencies, has to be

considered. In addition, the equipment has to be physically

rugged and electrically stable to operate successfully under

the several conditions of vibration, aerodynamic drag, and

temperature changes occurring during flights. The experiments

were conducted by transmitting two crystal-controlled c-w radio

-frequency signals, one of such frequency as to be substantially affected by the ionosphere and the other of such frequency
183

as to be essentially unaffected. Thus, since the antenna

pattern has to be favorable toward the receiving stations on

the ground, a diplexing whip antenna having a pattern similar to that of a dipole has replaced the earlier V-2 tail an- tennas. In recent flights, experiments were begun 80 seconds

after take-off at an altitude of approximately 35 miles. Autotune circuits were added to accomplish tuning, i. e. , matching between transmitter and antenna impedances, at this time

and a retuning unit was developed to initiate second tuning

at a much higher altitude. Antenna impedances during flight

could be determined from the telemetering data of the micromatch circuit and of the matching transformer variable condenser position. The problems connected with ionosphere

research instrumentation are no longer considered major

sources of difficulty, certain aspects of the antenna problem

which will still remain to be solved tend to reduce radiation

efficiency, but apparently do not introduce serious errors in

the propagation data provided that the rocket does not spin

or tumble. --Author's abstract.

A-623 Jackson, John E. , Measurements in the E-layer with the

Navy Viking rocket. Journal of Geophysical Research, 59(3):

377-390, Sept. 1954. 10 figs. , 8 refs. , 7 eqs. MH-BH--

Two signals of frequencies at a ratio of 1 to 6 were transmitted from the rocket, which reached a peak altitude of 174 km.

The highest altitude in which the Seddon experiment for the

determination of the electron density was performed up to this

time. For this purpose the indices of refraction were measured which decreased from about 1 at 90 km to 0. 72 at 110 km

(electron density 1. 3:k 105 el/cc) and further to 0. 61 at 165

km (density 1. 8 > lO^d/cc). Questionable data above height

show a rapid increase in the index. A value of 0. 488 oersted

was computed for the earth's magnetic field at 139 km with an

upper limit of 10^ per second for the electron collision frequency. Factors affecting the results are analyzed, especially

the role of the rocket. --A. A.

A-624 Jackson, John E. ; Kane, J. A. and Seddon, J. C. , Ionosphere electron-density measurements with the Navy Aerobee-Hi

rocket. Journal of Geophysical Research, Wash. , D. C. 61-

(4):749-751, Dec. 1956. 4 refs. Also: Jackson, John E. and

Seddon, J. Carl, Ionosphere electron-density measurements

with the Navy Aerobee-Hi rocket. Ibid., 63(1): 197-208, March

1958. 9 figs. , Table, 9 refs. , 2 eqs. DLC--In the first re- port, electron densities were measured at White Sands, N.

Mexico. , continuously from the E region up to the lower F2

region. This was done by measuring the Doppler shift in a

7. 75 Mc signal from the rocket. The electron densities measured were:
184

Ht PC 100 150 240 260

(km)

Electrons 104 1SX104 28X104 28X104 33X104

/cc

Electron densities measured on this flight (June 1956) were

about 50% greater above 100 km than those on the flight of

May 1954. This is in accord with the greater solar activity

since 1954. In the second report, electron densities in the

ionosphere above White Sands were measured continuously

from the E region up to the lower F2 region with Aerobee-Hi

NRL-50, a rocket instrumented by the U. S.N. R.L. The re- sults confirm the general structure of the daytime ionosphere

above White Sands as deduced from previous NRL flights,

namely that the ionosphere remains dense between the E and

F2 regions, with only minor valleys in the electron-density

profiles. The electron-density distribution is shown to be

consistent with the P'-f records obtained during the rocket

flight. The sporadic E condition, seen on these ionograms,

was found to be associated with a sharp spike in the electron-density profile at an altitude of 101 km and approximately 1 km thick. This sporadic condition extended over a horizontal distance of at least 80 km. --Authors' abstract.

A-625 Jackson, John E. and Kane, J. A. , Measurements of ionospheric electron densities using an RF probe technique . Journal of Geophysical Research, 64(8): 1074-1075, Aug. 1959.

fig. , 4 refs.

A-626 Jackson, J. E. and Kane, J. A. , Breakdown and detuning of

transmitting antennas in the ionosphere. U.S. ft aval Research Lab. , 1m RL Report, Upper Atmosphere Research Report No. 36, Aug. 24, 1959. 23 p. 15 figs. , table, 20

refs. , 19 eqs. DWB (Mil U58u) --Impedance measurements

made on a 7. 75 Mc rocket-borne antenna during several rocket flights indicate at altitudes above 110 km a capacitance

change whose magnitude can be used to determine ambient

electron densities. In the 50 to 100 km region the antenna

undergoes a radio frequency glow discharge resulting in a severe resistive loading and reduction of radiated power.

The properties of this breakdown were investigated both theoretically and by laboratory experiments. The use of a dc bias

on the antenna was found helpful in preventing breakdown.

The knowledge acquired from this project is being applied to

the development of improved rf probe techniques for the direct measurements of electron densities in the ionosphere. -- Authors' abstract.
185

A-627 Jackson, J. E. and Spaid, G. H. , Ground stations for NRL

rocket studies of the ionosphere . U. S. Naval Research Lab.,

NRL Report 5342, Upper Atmosphere Research Report No. 35,

Aug. 31, 1959. 33 p. 18 figs. , figs, in appendix, 11 refs.,

eqs. DWB (Mil U58u) --Between 1946 and 1958, a total of

23 rocket flights have been instrumented by NRL to measure

electron densities in the ionosphere and to investigate var- ious related phenomena. The measurements were based upon

the transmission of cw signals from a rocket to receiving and

recording stations on the ground. The nature of the experiments required phase comparisons between two harmonically

related frequencies. Since commercial receivers are unsuitable for this purpose, special receiving equipment was designed by NRL scientists to meet the experimental requirements. Particular considerations were given to bandwidth,

noise, dynamic range, phase stability, signal-strength metering, and input circuitry. The extremely narrow-bandwidth

operation which is possible with the cw method led to the design and use of a new type of crystal filter in the receiving

system. The need for separate reception of the ordinary and

extraordinary modes of propagation led to a novel adaptation

of the magic T at 7. 75 Mc. A two-station system, first used

at White Sands, New Mexico, was later, during IGY, transferred to Ft. Churchill, Canada. A number of unusually stable, narrow-band rf sweep generators were developed to test,

adjust, and calibrate the ground-station equipment. A greatly improved knowledge of the ionosphere at middle and arctic

latitudes has resulted from the data acquired at these ground

stations. --Authors' abstract.

A-628 Jackson, Willis (ed. ), Communication theory. Papers read

at a Symposium on "Applications of Communication Theory, " held at the Institution of Electrical Engineers, London, Sept . 22-26. 1952. London, Butterworth, 1953. 532 p. figs. , tables, refs. , eqs. DWB--The book consists of 40 articles

on communication theory of experts in all phases of this new

and important field. Among the subjects treated are coding,

feedback mechanics, noise and transmission through noise

by telegraph, radio, radar or television, storage time, propagation time, relaxation filters, transmission of drawings, color

television transmission, hearing, information in words or speech, telephone circuits, communication rate, semantic communication and application to optics. The possible applications to various phases of meteorological practice are too numerous to mention. The theory is applicable, for instance, in

telecommunication, radar and TV observation, coding of re- ports, teletransmission of automatic recording instruments,

radiosonde work and even library and bibliographic work. -- M.R.
186

A-629 Jacobs, George, Ionospheric propagation conditions . CQ,

Radio Amateurs' Journal, New York, 9(7) :41, 69, July 1953.

DWB--Regular column giving monthly outlook of radio propagation conditions, namely of possibilities in long-distance

communication, atmospheric noise, ionospheric storminess

and sporadic E or "short -skip" activity. --G. T.

A-630 Jaeger. J. C. , Equivalent path and absorption in an ionospheric region. Physical Society of London, Proceedings,

59(331) :87-96, 1947. --Computes and tabulates results on the

equivalent path and absorption for vertical incidence reflection or transmission on either side of a Chapman-region. Compares with results for parabolic distribution. The magnetic

field is not included. --L. A. M.

A-631 Jancel, Raymond and Kahan, Theo, Phenomenes electromagnetiques dans 1' ionosphere: Effets croises d'un champ mag- netique constant et d'un champ electrique oscillant. (Electromagnetic phenomena in the ionosphere: combined effect of

a constant magnetic field and an oscillating electric field.

)

Academie des Sciences, Paris, Comptes Rendus, 236(8): 788-

790, Feb. 23, 1953. 4 refs. , eqs. DLC--The effect of a constant magnetic field and an oscillating electric field on the

velocity distribution of free electrons in an ionized medium

is investigated by applying Boltzmann's general equation.

The results obtained include the particular cases of DRUYVESTEYN, CHAPMAN -COWLING and MARGENAU. --Transl.

of authors' abstract.

A-632 Jancel, Raymond and Kahan, Theo, Propagation des ondes

electromagnetiques planes dans l'ionosphere . (Propagation

of plane electromagnetic waves in the ionosphere. ) Academie des Sciences, Paris, Comptes Rendus, 236(21):2045-2047,

May 27, 1953. refs. DWB--The propagation of electromagnetic waves is described by a dielectric tensor based on the

Maxwell equations, computing the refraction indexes for particular cases. A formula for the attenuation of the waves and

for group velocities is derived. --A. A.

A-633 Japan. Science Council. Ionosphere Research Committee,

Report of Ionosphere and Space Research in Japan, Vol. 1,

1946(?)- Latest issue seen. Vol. 13, No. 2, 1959. (Note:

Vol. 1-Vol. 12 issued under title: Report of Ionosphere Research in Japan). DWB, DLC --(Holdings incomp. ) Each

issue contains a few substantial papers dealing with ionospheric cosmic -ray distribution, radio- wave propagation, magnetic storms, night-sky light measurements, electric conductivity of the ionosphere, etc. In the late issues (after 1950)

the articles are in English; in the earlier ones they are in
137

Japanese with English summaries. Most papers contain tabular and graphical data and mathematical analyses. Several

of the papers appear in this bibliography. --G. T.

A-634 Japan. Science Council. Ionosphere Research Committee.

Catalogue of disturbances in ionosphere, geomagnetic field,

field intensity of radio wave, cosmic ray, solar phenomena

and other related phenomena. No. 10, the 31st cooperative

observation, June 10-July 10. 1951. (1951?) Note: latest

such title is No. 29, April 19, 1958. 39 p. graphs, tables.

DWB--This observation period is especially interesting owing

to a great solar eruption with two severe magnetic storms and

a conspicuous decrease of cosmic ray intensity. A photo of

the eruption is added and the observation results are presented in numerous graphs and tables. --A. A.

A-635 Japan. Science Council. Nat. Committee for Geodesy and

Geophysics, Japanese national report on terrestrial magneti - sm and electricity. I U. G. G. Association of Geomagnetism

and Aeronomy, Rome, Sept. 1954, Transactions, pub. 1957.

p. 175-188, bibliog. p. 178-188. DWB, DLC--In addition to a bibliography of 247 Japanese papers published in 1950-1953

on geomagnetism, geoelectricity, atmospheric electricity,

sferics (20 refs. ), ionosphere, cosmic rays and solar-terrestrial relationships, this report contains brief notes on Japanese research achievements in each of these fields. --G.T.

A-636 Jastrow, Robert (Nat. Aero. & Space Admin. , Wash. ,D.C),

Symposium on the Exploration of Space: introductory remarks.

Journal of Geophysical Research, Wash., D. C. , 64(11):1647-

1651, Nov. 1959. DLC--The first nationally sponsored con- ference devoted to space physics was held April 29-30 in

Washington, D.C. The first session dealt with fields and

solid particles in the solar system and the second session

with the several aspects of space exploration. Brief comments

on two papers and three round table discussions are given. The

papers were: 1) Solid particles in the solar system (F. L. Whipple). 2) Plasma and magnetic fields in the solar system (T.

Gold). 3)Extension of the solar- corona into interplanetary

space (E. Parker). 4. The geomagnetically trapped corpuscular radiation (J. A. v. Allen). 5) Capabilities for space re- search (H. E. Newell). 6) The Moon (G. P. Kuiper). 7) Primary

and secondary objects (H. C.Urey). 8) Remarks on Mars and

Venus (G. de Vaucouleurs). 9) Rocket astronomy (H.Friedman). 10) Astronomy from satellites and space vehicles (L.

Goldberg). 11) Experimental research program on the space

sciences, and 12) Outer atmospheres of the earth and planets.

--G.T.
188

A-637 Jean, A. Glenn, Jr. ; Lange, L. Jerome and Wait, James R. , Ionospheric reflection coefficients at VLF from sferics measurements. Geofisica Pura e Applicata, Rome, 38:147-153,

1957. 7 figs. , 4 refs. , 4 eqs. English summary. DLC--

A method for calculating the complex ionospheric reflection

coefficients at VLF using sferic wave forms is presented.

The mathematical analysis was carried out for a number of

different wave forms to illustrate the method. Reflection

coefficients determined from sferics observations were compared with those calculated, using an ionospheric model. In

most cases, the agreement with theory is fairly good, although in some cases, reflection coefficients exceeding unity

were obtained. The discrepancies are believed to result from

horizontally polarized flashes rather than limitations in the

ionospheric model. --Authors' abstract.

A-638 Jeffrey, Z. R. , Hourly measurements of ionospheric characteristics. Macquarie Island, 1951. Australian National Antarctic Research Expedition, 1947-1949, Interim Reports, No.

6, 1953. p. 82-220. Mostly tables. DLC (QC973.J4)-

Graphs and tables for every month of 1951 for Macquarie Island. --M. R.

A-639 Jenkins, J. B. and Ratcliff, The investigation of ionospheric

absorption by a new automatic method, Pt. 1: Measurements

on vertical incidence pulse signals. Electronic Engineering,

25:140, 1953. --Equipment is described which automatically

measures echo pulse amplitude and produces records, at minute intervals, of the integral of all echo pulse amplitudes re- ceived during each minute. The output of a modified communications receiver, blanked so as not to respond to the transmitter pulse, is fed to two gated amplifiers, one of which

selects the echo signal and associated noise, while the other

deals with noise only. After integration for 1 min, the difference of the output voltages of the integrators is applied to a pen recorder, the integrators at the same time being reset

to zero. Under good conditions, with little rapid fading, the

results obtained are in good agreement with results noted by

a skilled observer from a CRO display of the transmitted and

echo pulses. Wide differences are found under poor conditions, with rapid fading, and the results furnished by the au- tomatic equipment, are considered the more reliable.

A-640 Johler, J. R. ; Walters, L. C. and Lilley, CM., Transfer

characteristics of radio waves propagated between the Dregion and the E-reqion of the ionosphere and the earth based

on the quasi-longitudinal theory. U.S. National Bureau of

Standard, Boulder Laboratories Report 6002, Sept. 15, 1958.

197 p. 24 figs. , 123 tables, 15 refs.
189

A-641 Johnson, Charles Y. and Heppner, James P. , Daytime measurement of positive and negative ion composition to 131 km

by rocket -borne spectrometer. Journal of Geophysical Research, Wash., D.C. , 61(3):575, Sept. 1956. foot-ref. DLC

—The positive and negative ion composition from 5 to 60 atomic mass units was measured between 93 and 131 km by spectrometers in an aerobee rocket at 10:16 MST, Nov. 1955. No

positive ions were detected during this daytime flight. Negative ions were detected as follows:

Atomic Mass No. 46 32 29 22 16

Relative abundance 96 1.6 0.2 1.0 0.7

Probable identification N0o

" o; ? ?

0"

Positive ions would have been detected if their concentration

had been as much as the negative ions of masses 16 and 29.

-S. F.

A-642 Johnson, Francis S. , The ion distribution above the F2

maximum. Journal of Geophysical Research, 65(2): 577-584,

Feb. 1960. 3 figs. , 24 refs. , 8 eqs. DLC.

A-643 Johnson, R. and Strandberg, M.W. P., Broadening of microwave absorption lines by collisions with the cell walls . Physical Review, 86(5):811-812, June 1, 1952.

A-644 Joint Technical Advisory Committee (IRE-RTMA), Radio

spectrum conservation: program of conservation based on

present uses and future needs. A report of the Joint Committee of the Institute of Radio Engineers and the RadioTelevision Manufacturers' Association. N. Y. , McGrawHill, 1952. 221 p. figs., bibliog. p. 199-208. DLC

(HE8667. J65)--This survey gives an evaluation of the radio

spectrum related to industrial scientific and medical use. Allocations of different frequency bands are suggested, and

some general characteristics of propagation at different frequencies are discussed. in relation to meteorological conditions in the ionosphere and troposphere. --W. N.

A-645 Joint Technical Advisory Committee (IRE-RTMA), Radio

transmission by ionospheric and tropospheric scatter. Pt. 1,

Ionospheric scatter transmission. Institute of Radio Engineers, Proceedings, 48(l):4-29, Jan. 1960. 23 figrs. , tables,

83 refs. Pt. 2, Long-range tropospheric transmission. Ibid.

,

p. 30-44. 10 figs. , tables, 43 refs. DLC "This is a supplement to the earlier comprehensive report issued by the

Joint Committee of the Institute of Radio Engineers and the

Radio-Television Manufacturers Association. Radio spectrum conservations, published N. Y. , McGraw-Hill, 1952".

--The ionospheric and tropospheric scatter communication

techniques are summarized individually. The present knowledge on ionospheric propagation theories, instrumentation,
190

practice, etc. including frequency allocation is treated in

the first part. Second part deals with the same as applied

to troposphere. --W. N.

A-346 Jones, I. L. ; Landmark, B. and Setty, C. S. G. K. , Movements

of ionospheric irregularities observed simultaneously by dif - ferent methods. Journal of Atmospheric and Terrestrial Physics, 10(5):296-301, 1957. 4 figs. , 2 tables, 11 refs. , eq.

DWB--Velocities of irregularities in ionospheric layers were

determined by 4 different methods, one using 3 receivers about one wave-length apart, the others at 3 points about 15 km

apart near Cambridge, Eng. Results agree well, showing

that large irregularities had the same movements as those

which produced ordinary fading. --C. E. P. B.

A-647 Jones, I.L. (Cavendish Lab. , Cambridge), The height variation of horizontal drift velocities in the E-region. Journal

of Atmospheric and Terrestrial Physics, London, Special Supplement, 1957 (Proceedings of the Polar Atmosphere Symposium, Oslo, 1956, Pt. 2), issued 1958. p. 20-22. fig. , 3

refs. DLC --Observations of ionospheric drift velocities have

been made simultaneously on two neighboring frequencies.

The frequencies used were 2 Mc/s and about 2. 5 Mc/s, so

that during the daytime, reflections were obtained from the

E-region. The heights of reflection on the two frequencies

differed by about 5 km, thus information about the drift at

heights separated by this amount could be obtained. During

the winter months it was found that the phase of the semidiurnal component of velocity, varied with height, the phase

being advanced with height. The fact that the results from

the neighboring reflection heights are different, suggests that

they are representative of the conditions near those heights.

The phase change with height is consistent with the observations made on drifting meteor trails. --Author's abstract.

A-648 Jones, I.L. (Cavendish Lab. , Cambridge, Eng.), Theoreti - cal views on drift measurements . Journal of Atmospheric and

Terrestrial Physics, London, Special Supplement, 1957 (Proceedings of the Polar Atmosphere Symposium, Oslo, 1953,

Pt. 2), issued 1958. p. 3-11. 9 figs. , 3 refs. , eq. DLC--

Measurements of ionospheric drifts by observing the fading

of a singly reflected wave at three closely spaced points on

the ground are discussed. The magnitudes and directions of

drift velocities observed from time delays between maxima

and minima of the fading records are subject to large variations. These can be explained partly in terms of the variable

orientation of a line of maximum amplitude and partly by changes in the amplitude pattern as it moves. The drift observed

when the pattern on the ground is anisometric may be markedly
191

different from the true drift, and tends to lie in a direction

perpendicular to the direction of stretching. The effect on

the average drift due to random orientation of the stretching

and due to stretching in a preferred direction is discussed.

When the amplitude variations at three stations are available,

the auto-correlation and cross -correlation functions can be

determined. From these, it is possible to determine the true

magnitude and direction of the drift, the size and shape of

the amplitude pattern on the ground and also a quantity re- lated to the random changes of the pattern. --Author's abstract.

A-649 Jones, Robert E. , Millman, G. H. and Nertney, R.J., Scientific report on the heights of ionospheric winds as measured at long radio wavelengths. Pennsylvania. State College,

Ionosphere Research Laboratory, Contract AF 19(122) -44,

Scientific Report No. 36, April 30, 1952. 18 p. 12 figs.

,

22 refs. , 14 eqs. DWB--The existence of winds in the ionosphere can be shown using the results obtained from spaced

receivers. The height of these winds must occur at or below

the reflection level of the frequency used (in this case 150 kc

sec" pulses). A method for obtaining this additional information is developed and a frequency distribution of apparent

wind heights is given. The daytime winds, measured at 150

kc sec'l probably occur around the 75 km height,the nighttime winds between 83 to 100 km. --A. A.

A-650 Jones, Robert E. , Millman, George H. and Nertney, R. J.

,

The heights of ionospheric winds as measured at long radio

wavelengths. Journal of Atmospheric and Terrestrial Physics,

London, 3(2):79-91, Feb. 1953. 7 figs. , 13 refs. MH-BH--

Use of delta phase height equipment for obtaining heights at

which ionospheric winds occur show daytime winds at about

75 km level and night-time winds at between 83-100 km. -- G.J.E.

A-651 Jones, Robert E. , Physical characteristics of the lower Eregion as deduced from the measurement of changes in phase

path of long radio waves. Pennsylvania. State College.

Ionosphere Research Laboratory, Contract AF 19(122) -44,

Scientific Report, No. 48, Aug. 25, 1953. 88 p. 32 figs.

,

3 tables, 38 refs. , 42 eqs. DWB—The diurnal and seasonal

variations in phase height of the main E region reflection

level at 150 kc at State College, Pa. , are reported for a period of 15 months. An electron density model, moderately

"sharp" on the lower side, is evolved by modification of the

Chapman theory to include the effects of variable scale height, dissociation of molecular oxygen, and variable recombination. This model is checked, primarily, against 150 kc
192

phase height data, but also against 2. 4 mc phase heights,

height of maximum ionization, and critical frequency results.

The comparison of periods of oscillation in phase with fading

periods is shown to bear out the theoretical work on the ionospheric diffracting screen. --Author's abstract.

A-652 Jones, Robert E. , The development of an E-region model con- sistent with long wave phase path measurements. Journal of

Atmospheric and Terrestrial Physics, 6(1): 1-17, Jan. 1955.

10 figs. , 2 tables, 32 refs. , 9 eqs. DWB--Diurnal changes

in phase height of 150 kc radio signals reflected from lower

E region, observed in Pennsylvania, are plotted. Mean range

is 15 km in summer, 15. 5 at equinoxes and 11. 5 in winter.

Several new ionosphere models are discussed, starting with

CHAPMAN'S (1931) and incorporating effects of variable

scale height, dissociation of 02 and variable recombination.

That finally chosen (fig. 6, moderately sharp on the lower

side) is the best compromise but is not entirely satisfactory

because of the uncertainties involved. --C. E. P. B.

A-653 Jones, Robert E. , Ionosphere research. Pennsylvania. State

College, Ionosphere Research Laboratory, Contract AF 19

(122)-44, Final Report, March 25, 1949-Jan. 31, 1955. Jan.

31, 1955. 105 p. bibliog. Mimeo. DWB-Over 200 reports

and scientific papers, which have emanated from this project

in 5-1/2 years, are listed and abstracts given on all of the

scientific reports. Personnel and history of the project are also outlined. The investigations cover a wide range of studies on the ionosphere, especially the lower ionosphere.

These are listed and discussed under the following heads:

1) Low frequency (long wave) studies, 2) Electromagnetic

studies (wave solutions, coupling theory and total polarization), 3) Ionospheric physics (solar and high atmospheric

physics, D-region viscosity, dynamics of ionized media, effect of vertical ion transport), 4) Ionospheric properties (coupling phenomena, E layer characteristics, ionospheric winds

and wave interaction), 5) Applied propagation investigations

(oblique incidence studies), 6) Extra terrestrial studies (ring

current and electrodynamics of very high atmosphere) and 7)

Long wave equipment developed. --M. R.

A-654 Jouaust, Raymond, Influence of wind on the frequency of

radio waves. Academie des Sciences, Paris, Comptes Rendus, 226(4): 329-330, Jan. 26, 1948. -It is suggested that the

results obtained by Decaux may be due to ionospheric winds

which give rise to Doppler effect. --Wireless Eng. Abstr. 1726.

A-655 Jouaust, Raymond, L'etat de nos connaissances sur 1 'ionosphere et ses relations avec le magnetisme terrestre. (The
193

status ol our knowledge ol the ionosphere and ot its relations

to terrestrial magnetism. ) (In: Problemes de Geomagnetisme,

J. P. Rothe, et al. Paris, Revue d'Optique Theorique et In- strumental, 1950. p. 65-76. ) Biographical note on Jouaust,

t>. 76. DLC- -Textbook type treatment. --M. R.

A-656 Jowett, J.K.S. and Evans, G. O. , A study of commercial

time lost on transatlantic radio circuits due to disturbed iono- spheric conditions . Institution of Electrical Engineers, London, Proceedings, Pt. B, 102(4): 505-512, July 1955. 6 figs.,

11 refs. DLC --An analysis has been made of the time lost on

certain radio circuits incoming to the United Kingdom from

Montreal and New York during the period 1942-1952. The re- sults have been examined in relation to the variations in solar

and magnetic activity with a view to estimating the degree

of interruption likely to be experienced on transatlantic circuits during the next few years. It is concluded that the

maximum values of lost time occur during the winter months

as the minimum of the sunspot cycle is approached, and that

these high values are associated with periods of high magnetic activity arising from the occurrence of M-region storms.

It is considered that the adverse propagation conditions en- countered since the winter of 1950-51 will be slightly less

severe during the winter of 1954-55 and that by the winter of

1955-56 there should be a marked reduction in the amount of

commercial time lost on transatlantic circuits. --Authors' abstract.

A-657 Junakovic, F. , Nevto o radio vezi u meteoroloskoi sluzbi.

(Radio communication in the meteorological service. ) Yugoslavia. Hidrometeoroloska Sluzba, Vesnik, 1(3/4) :63-68,

July/Oct. 1952; 1(5): 100-104, Nov. /Dec. 1952. 5 figs. DWB

--Current knowledge on ionospheric short-wave radio propagation is summed up. The effect of solar activity, of ionized

clouds, of magnetic disturbances, etc. is discussed. The

two-wave-length broadcasting technique of the Yugoslav Federal Broadcasting Center, which is destined to cover both

short and long distance, is explained. --G. T.

A-658 Kalinovskii, Aleksandr Boleslavovich and Pinus, N. Z. . Aeroloqiia; metodv aeroloqicheskikh nabliudenii. (Aerology; methods of aerological observations. ) Leningrad, Gidromet. Oizdat. , 1951. 452 p. 245 figs. (incl. photos), tables, footrefs. , eqs. , 164 refs. , p. 423-428. DLC--A unique textbook

for students intending to pursue practical hydrometeorological

or aerological work. The various chapters consist of I. History and development, especially in U. S. S. R. ; II. Pilot balloon observations; III. Meteorograph and its calibration, ac- curacy and corrections; IV. Kite, captive and manned balloon
194

observations; VI. Airplane soundings; VII. Computations of

meteorograph records; VIII. Radiosondes (various types described in detail and compared); IX. Radio-location applied

to soundings; X. Measurement of vertical currents; XI. Cloud

and cloud physics measurements; XII. Rocket research; XIII.

Publication of aerological "yearbooks" or summaries and machine methods of computation (80 column IBM -type cards and

punchers, sorters and tabulator illustrated). The detailed

theory that enters into each method of observation or instrument use; calculation of data, etc. , and actual comparative

values, accuracy of instrument elements, design and construction of instruments and photographs of equipment are included. The bibliography of 164 references arranged by chapters consists mainly of Russian sources, but a dozen or more German, U. S. or British references are cited. Material as recent as 1950 is included. Chapter on rockets gives

comparative data for V-2 and Wac -Corporal Rocket flights

and standard atmospheric data to 100 km height. Chapter on

radio location includes brief mention of radar storm detection

methods. --M. R.

A-659 Kallmann, H. Korf, A study of the structure of the ionosphere. Rand Corporation, Santa Monica, Calif. , (Papers),

P. -638, Feb. 1955. 164 p. 14 figs, (some fold. ), 18 tables

(some fold. ), 162 refs. , 53 eqs. Thesis (Ph. D. ), Univ. of

Calif, at L. A. (1953?) DWB--An attempt at a realistic model

of the upper atmosphere and ionosphere, based on the latest

observational and theoretical results, especially with rockets,

radio and acoustical soundings, meteor trail studies and auro- ral-airglow spectroscopy. Chapters include history, technique, physical properties up to 80, and from 80-220 km; the

solar atmosphere, theory of ionization and recombination plus

extensive numerical tables and diagrams giving coefficients,

spectroscopic data, constants, observational data and models

of the various elements. --M. R.

A-660 Kallmann, H. K. , Electron distribution in a new model of

the ionosphere. California. Univ. Institute of Geophysics.

Contract AF 19(604) -111, Scientific Report, No. 4, Jan. 1956.

8 p. 4 figs. --A new model of the ionosphere, based on rocket data for electron densities rather than radio echo data,

shows a more homogeneous ionosphere with the E, F 1 and F2

regions merging gradually into each other rather than being

widely separated or stratified. It indicates a heavy ionization in the 100-200 km region, and low electron density gradients at very low altitudes. The maximum of the Fl region

would occur about 165 km. The discrepancy lies in the concept of virtual heights which may prove to be 50 to 100% too

high owing to slight gradient variations in a supposedly thick

ionosphere. --M. R.
195

A-661 Kallmann, H. K. ; White, W. B. and Newell, H. E. , Jr.,

Physical properties of the atmosphere from 90 to 300 kilometers: proposed "Speculative Atmosphere" submitted to the

Working Group on Extension to the U. S. Standard Atmosphere

Tables. Journal of Geophysical Research., Wash., D.C.,

61(3): 513-524, Sept. 1956. 3 figs. , 2 tables, 19 refs. , 22

eqs. Erratum Ibid. , 62(1):168, March 1957. fig. DLC--

Based on recent experimental and theoretical studies of the

physical properties of the atmosphere at high altitudes, an

average model atmosphere is presented for the region between

90 and 300 km. This model is consistent with the following

assumptions: Molecular oxygen begins to dissociate appreciably only above 90 km; at around 130 km, about 30% of 02

is still in the undissociated state; molecular nitrogen begins

to dissociate above 220 km; the concentrations of molecular

oxygen and nitrogen decrease with altitude exponentially;

the temperature becomes isothermal in the region of the exosphere, approximately above 360 km. All physical quantities

have been calculated from self-consistent equations as con- tinuous functions of altitude, without assuming any particular form of the temperature gradient. The results show lower

temperatures and densities throughout the region of the ionosphere than have been deduced previously. --Authors' abstract.

A-662 Kallmann, H. Korf (Univ. of California, Los Ang. ), Un nouveau modele d' ionosphere. (New model of the ionosphere.

)

La Meteorologie, Paris, Ser. 4, No. 52:235-243, Oct. /Dec.

1958. 7 figs. , English and Spanish summaries p. 236. DWB

--After showing the reason for the considerable differences

between the constitution of the ionosphere as given by experiments of radio wave reflection at different frequencies and

as given by recordings made with rockets fired to a high altitude; the author explains that the Chapman theory, used up

to the present under a simplified form, must not be blamed.

In fact, thanks to the recent data supplied by rockets, it can

account for the structure of the ionosphere. Results thus

given are so satisfactory that although numerous uncertainties subsist, it offers a new image of the ionosphere; it is

not composed of ionized layers but rather of a strongly ionized region of large thickness with weak variations of electron densities. --Author's abstract.

A-663 Kallmann, H. K. , A preliminary model atmosphere based on

rocket and satellite data. Journal of Geophysical Research,

64(6): 615-623, June 1959. 5 figs. , 3 tables, 32 refs.

A-664 Kalra, S.N., Frequency measurement of standard frequency

transmissions . Canadian Journal of Physics, 38(3):513,

March 1960.
196

A-665 Kamada, Tetsuo and Nakajima, Jun, The measurement of

the intensity of atmospherics, Pt. 1. Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 2:31-39, Jan.

1954. 13 figs. , table, 6 refs. DWB--An apparatus for re- cording intensities of sferics and its methods of operation

are described. Results obtained with the instrument at the

Research Institute of Atmospherics at Toyokawa, Japan, are reported. Data on diurnal, monthly and seasonal intensity

variations, on sferics intensity as a function of the frequency used and on phenomena connected with sunrise, sunset

and solar flares are presented and interpreted.-- G. T.

A-666 Kamada, Tetsuo and Nakajima, Jun, On the direction of ar- rival of atmospherics at Toyokawa. Pt. 1. Nagoya. Univ.

Research Institute of Atmospherics, Proceedings, 2:95-101,

Jan. 1954. 22 figs. , 3 refs. DWB-As a result of continuous recordings of direction of atmospherics made at the Research Institute of Atmospherics in Japan (137 E, 35 N),

monthly and seasonal average directional frequency distribution diagrams are presented for the period July 1952-Dec.

1953. -G.T.

A-667 Kamiyama, Hiroshi, Seasonal variation of the minimum frequency in h°-f curve for the "E" ionospheric region. Tohoku

University, Science Reports, 5th Ser. , Geophysics, 2(2):79-

85, Aug. 1950. 5 figs. , 4 tables, 10 refs. , 17 eqs. In English. MH-BH--The minimum critical frequency in the E layer

at noon is found to be proportional to cos3/4 (zenith distance

of sun at noon). This supports the existence of an ionized D

layer about 55 km. and variations from the cos -law may give

information about temperature in the middle stratosphere. -- C E. P. B.

A-S68 Kamiyama, Hiroshi (Geophysical Institute, Tohoku Univ. ), Ionospheric changes associated with geomagnetic bays . Tohoku Univ. , Science Reports, 5th Ser. , Geophysics, 7(3):

125-135, March 1956. 4 figs. , 3 tables, 18 refs. , 14 eqs.

DWB, DLC--It is assumed that the ionospheric currents cor- responding to geomagnetic bay disturbances in the temperate

latitude are produced by the electro-statical field developed

by the current system in the auroral zone. Taking account

of the ionization drift due to this electric field and the earth's

magnetic field, the deviation in the electron density from its

normal condition is examined. The depression of the electron

density in the ascending ionospheric region and the ionic concentration in the descending region, which we often notice

during magnetic disturbances, are explainable by assuming a height gradient of temperature in the upper atmosphere. --Author's abstract.
197

A-669 Kamiyama, Hiroshi and Sato, Teruyuki (both, Geophysical

Inst. Tohoku Univ. ), The latitudinal effect on the disturbance

daily variation in F2 layer of the ionosphere. Tohoku Univ.

,

Science Reports, 5th Series, Geophysics, 8(1):41-51, Nov.

1956. 3 figs., 2 tables, 7 refs., eq. DWB, DLC -The so- called S£)(Nm) in the F2 region of the ionosphere are expressed

by Fourier series; it is found that the amplitudes are controlled

by the geomagnetic latitude and the phases are depending on

the geographic latitude. The latitudinal distributions of the

harmonic coefficients show marked seasonal changes. In equinoctial months the distributions are almost symmetrical about

the equator, but in solstitial months, the axes of symmetry are removed towards the winter hemisphere. Equal deviation charts

for different seasons are given. --Authors' abstract.

A-670 Kamiyama, Hiroshi and Sato, Teruyuki (both, Geophysical

Inst. , Tohoku Univ. ), The distribution of the electrical con- ductivity in the ionosphere and its variations. Tohoku University, Science Reports, Fifth Series, Geophysics, 9(2):55-80,

Oct. 1957. 19 figs. , 2 tables, 27 refs. , 43 eqs. DWB, DLC

--The ionospheric conductivity is estimated on the basis of the

atmospheric model derived from rocket data. The collisional

frequency with which the conductivity is closely related depends not only on the density and the temperature of the atmosphere but also on the concentrations of the electrons and ions.

The dependency is examined at various altitudes. Consequently, the conductivities longitudinal and transverse to the earth's

magnetic field, and the Hall conductivity are evaluated for var- ious values of electron concentrations. These results are applied to the vertical and geographical distributions of the conductivities and their daily, seasonal and sunspot-cycle variations. The conductivity is almost proportional to the electron

concentration except in the lower E region, and in the F region.

In the F region, it is more sensitive to the electron concentration than in the lower region. --Authors' abstract.

A-671 Kamiyama, Hiroshi, A study on the formation of the ionos - pheric layers. Tohoku Univ. , Science Reports, Fifth Series,

Geophysics, 11(2):98-112, Sept. 1959. 8 figs., 2 tables, 35

refs. , 31 eqs.

A-672 Kamiyama, Hiroshi, Remarks on the electrical conductivity of

the ionosphere . Tohoku Univ. , Science Reports, Fifth Series,

Geophysics, 11(2): 73-83, Sept. 1959. 10 figs., 4 refs. , 2 eqs.

A-673 Kamiyama, Hiroshi, Vertical distribution of molecular oxygen. Tohoku Univ. , Science Reports, Fifth Series, Geophysics,

ll(2):84-97, Sept. 1959. 3 figs. , 5 tables, 23 refs. , 53 eqs.
198

A-674 Kane, J. A. (U. S. Naval Res. Lab., Wash., D.C.), Arctic

measurements of electron collision frequencies in the D-region

of the ionosphere . Journal of Geophysical Research, Wash.

,

D.C., 64(2): 133-139, Feb. 1959. 4 figs., table, 12 refs. , 14

eqs. DLC --Electron collision frequencies in the D-region were

measured with the aid of rockets launched during polar blackouts at Fort Churchill, Canada (58 N). During the blackouts

the ionization content of the D-region was large enough to

cause a strong altitude-dependent absorption of a 7. 75 Mc/s

CW signal, radiated from the rocket. The refractive indices

and the difference absorption of the two magnetic-ionic components of this signal were simultaneously measured versus

altitude. The electron collision frequency profile was then

determined from these measurements. The results from two

midday rocket flights, one made in July 1957, and the other in

Nov. 1956, indicates that the electron collision frequencies

in the Arctic D-region are lower by a factor of three than the

standard values calculated by Nicolet (1957). At 70 km the ._ measured value of the collision frequency is (1. + 0. 3) X 10

sec" • --Author's abstract.

A-675 Kay, I. , On the measurement of virtual height. N. Y. Univ.

Institute of Mathematical Sciences. Div. of Electromagnetic

Research, Contract DA-49-170-Sc-2253, Research Report

MME-5, July 1957. 11 p. 3 refs. , eqs. DWB (538 N532r)-

A time dependent definition of virtual height of a reflected

wave train is given so that its accuracy increases as the width

of the incident pulse increases. An example is given of a re- flected wave whose virtual height cannot be determined by inspection, but which can be determined correctly from the given

expression. --From author's abstract.

A-676 Kazantsev, A.N., O pervykh nabliudeniiakh nochnogo ionizirovannogo sloiia, lezhashchego vyshe sloia F2 . (First observations of the nocturnal ionized layer above F2 layer. ) Akademiia Nauk SSSR, Doklady, 59(3):479-482, Jan. 21, 1948.

4 figs. , 2 refs. DLC--In connection with N. A. MEDNIKOVA's

discovery in Feb. 1947 , the author presents a ser- ies of extracts (with graphs) of reports (some previously published) on the measurement of effective heights of ionized lay- ers between sunset and sunrise carried out by him near Moscow

during the period 1933-1937 in which the F2 layer was recorded.

Author points out that: 1) the critical frequency of the layer is

smaller than the one of the F2; 2) it can be observed by disturbed condition of the atmosphere and its probably produced

by corpuscular radiation of the sun and 3) as a rule, it is a night phenomenon appearing around sunset and vanishing at

sunrise. --A. M. P.
199

A-677 Kazantsev, A. N. , Absorption and electron distribution in the

F2 layer determined from measurements of transmitted radio

signals from earth satellites. Planetary and Space Science,

1(2):130-135, April 1959. 6 figs. , 3 refs. , 7 eqs. DLC.

A-678 Keitel, G. H. , The Program of a two-dimensional scattering

problem for an automatic sequenced digital computer. Stanford University, Electronics Research Laboratories, Contract

AF 19(604)-1031, Scientific Report No. 6, Aug. 1955.

A-679 Keitel, G. H. , An extension of Milne's three point method.

Stanford University, Electronics Research Laboratories, Contract AF 19(604)-1031, Report No. 6, Dec. 1956.

A-680 Keitel, G. H. , On the dipole resonant mode of an ionized gas

column. Australian Journal of Physics, 9(1):144-147, March

1956.

A-681 Keller, Herbert B. , Ionospheric propagation of plane waves.

N. Y. Univ. Washington Square College, Mathematics Research Group, Contract AF 19(122)-42, Research Report, EM

56, Aug. 1953. 41 p. fig. , 13 refs. , numerous eqs. DW6--

The propagation of plane waves in a stratified ionosphere is

considered. It is shown that the construction of "true" characteristic waves depends upon the diagonalization of a matrix by

a Loewy transformation. For a homogeneous ionosphere this

construction can always be carried out explicitly. For the general case we obtain the wave solution in terms of characteristic waves which have the properties usually attributed to characteristic waves in magneto-ionic theory. In addition, the interaction between these waves is made clear by the introduction of continuous reflection and transition coefficients. Ordinary and extraordinary wave reflection levels are shown to

be points at which the elementary divisors of a certain matrix

become non-simple. Complicated expressions are obtained

from which ionospheric reflection and transmission coefficients

may be obtained explicitly. Explicit solutions are obtained for

normally incident waves with an oblique earth's magnetic field

and for oblique incident waves with a vertical earth's magnetic

field. --Author's abstract.

A-682 Keller, Herbert B. , On the electromagnetic field equations in

the ionosphere. N. Y. Univ. Washington Square College,

Mathematics Research Group, Contract AF 19(i22)-42, Research Report, EM-57, Sept. 1953. 17 p. fig., 5 refs. , eqs.

DWB--This paper consists of two notes on the equations governing the propagation of electromagnetic waves in the ionosphere. In Part I, the tensor properties of the ionosphere are derived by a method due to VAN DER WYCK. While we
200

introduce only minor improvements on his method, it was felt

worthwhile to make these results generally more available.

Part II shows the equivalence of various forms of the propagation equations. A general scheme is indicated for finding

simplifying transformations of the equations in their first-order

form. In particular, we obtain that transformation which yields

Rydbeck's coupled equations and give an interpretation. --Author's abstract.

A-683 Kelley, Luther C. , Forecast of ionospheric storms and radio

communications, 1959-1962. U. S. Army Signal Radio Propagation Agency, Ft. Monmouth, N. J. , June 1958. (Project 636).

A-684 Kelso, JohnM., The maximum height of reflection of a radio

wave in a curved ionosphere layer. Pennsylvania. State College. Radio Propagation Laboratory, Contract AF 19(122) -44,

Technical Report, No. 1, May 1, 1949. 4 p. graph, 3 refs. , 7 eqs. DWB--There is an upper limit to the possible height of

reflection in a curved ionosphere (below the level of maximum

ionization) where the signal will travel through the layer. This

is presented theoretically by an expression derived from the

double parabola approximation to the Chapman distribution of

ionization as a function of height. --W. N.

A-885 Kelso, John M. , Approximate solutions of some problems in

the theory of ionospheric radio wave propagation. Pennsylvania. State College. Radio Propagation Laboratory, Contract,

AF 19(122) -44, Technical Report, No. 2, June 1, 194S. 146

p. 46 figs. , 31 refs. , 127 eqs. DWB--A dissertation for the

Ph.D. degree at Penna. State College. The double parabola

approximation to the Chapman distribution of electron density

as a function of heioht is applied to propagation via the E layer . Analytical expressions are given for: (1)

the true and group heights of reflection, (2) ray paths, (3) re- flection coefficient, (4) ionospheric range, (5) ground range,

(6) MUF for the Sellmeyer dispersion theory, plane ionosphere

and earth geometry. Graphical results are given for MUF. The

results are compared with the dispersion theories of LORENTZ

and of SELLMEYER, the scale heights and height of bottom layer of which are discussed. A method for determining the collision frequency at maximum ionization level is suggested.

Another method that will determine whether the Sellmeyer or the Lorentz dispersion should be used in ionospheric calculation is outlined. --W.N.
201

A-686 Kelso, John M. , Elliptical polarization and its application

to the polarization of ionospherically reflected long radio

waves. Pennsylvania. State College. Radio Propagation Laboratory, Contract AF 19(122) -44, Basic Ionospheric Research,

Technical Report, No. 11, June 1, 1950. 37 p. 22 figs.

,

tables, 10 refs. , eqs. DWB--The problem of polarization of

ionospherically reflected radio waves is discussed in detail.

Author demonstrates that the statement of TAYLOR and MARTIN "that the polarization ellipses of the two magneto-ionic

are always oriented so that their major axes are perpendicular"

is not generally true. --W. N.

A-687 Kelso, John M. , The effect of the Lorentz polarization term

on the vertical incidence absorption in a deviating ionosphere

layer. Institute of Radio Engineers, Proceedings, 39(4) :412-

419, April 1951. 4 figs. , 15 refs. , 34 eqs. MH-BH--The topic

computed and discussed leads to the conclusion "that with sufficient sensitivity in the measurement of the reflection coefficient, it may be possible to use this material in deciding whether the Lorentz or Sellmeyer theory of dispersion should be

used in ionospheric calculations. "--From author's abstract.

A-688 Kelso, J. M. ; Nearhoof, H. J. ; Nertney, R.J. and Waynick,

A.J. (Ionos. Res. Lab., Penna. State Col.), The polarization of vertically incident long radio waves. Annales de Geophysique, Paris, 7(4):215-244, 1951. 2 figs. , 20 refs. , eqs.

English and French summaries p. 215. MH-BH--The polarization of long electromagnetic waves in the ionosphere is considered. The analytical expressions relating N - v distributions of the ionosphere to the characteristic polarizations are developed. The polarization of the electromagnetic waves

leaving the ionosphere is treated in two ways. In Part I the

wave is treated as a single magneto-ionic component. It is

shown that under certain conditions the wave does behave as

a single component which attains a "limiting polarization" at

some N value, N/0. It is shown, however, that this analysis

"breaks down" under certain conditions and, in fact, wave polarizations occur which are not characteristic polarizations as- sociated with any N - v value. It is shown in Part II that a model consisting of electron D and E regions is capable of

giving polarization results which are in good agreement with

experiment. --Authors' abstract.

A-689 Kelso, John M. (Penna. State Col. , Ionosphere Res. Lab. ), A procedure for the determination of the vertical distribution

of the electron density in the ionosphere. Journal of Geophysical Research, 57(3):357-367, Sept. 1952. 3 figs. , 11 refs.

,

26 eqs. DWB. Comments by L. A. Manning, Ibid., 58(1):117-

118, March 1953. And Comments by D. H. Shinn, Ibid. 58(3):

416-418, Sept. 1953.--
202

A procedure is given for the determination of the "true height

of reflection" of a radio wave incident vertically on the ionosphere. Since — for a given operating frequency — the electron

density required for reflection is easily found, the present procedure allows the electron density to be determined as a function of height. To find the "true height" at some particular frequency, fv , it is only necessary to take the average of the

values of group height measured at a set of predetermined frequencies. These frequencies depend on fv

and the accuracy

desired in the results. In scaling standard experimental curv- es for this work, it was sufficient to use five values except

near cusps or steps where double that number was found desirable. The present method is based on the use of the GaussChristoffel quadrature formula, which is used for the numerical

integration of the well-known integral for "true height" as a function of group height. The restrictions on this integral apply to all of the work contained here and are: (1) the earth's

magnetic field is neglected; (2) The effects of collisions are neglected; (3) It is assumed that ray theory may be used; (4)

It is assumed that the curve of electron density as a function

of height has no maxima or minima in the region considered.

MANNING points out that Kelso's method of computing the

electron density in the ionosphere by a numerical integration

of vertical height and frequency data gives results no different from those which would be obtained by simple averaging

of equally weighted, evenly spaced ordinates. SHINN further

shows that although KELSO 's method gives good results for

integrating such empirically derived data, it is not as accurate

as KELSO claims, and shows special cases where the error sould be larger. --M. R. , W.N.

A-690 Kelso, John M. (Penna. St. Coll., lonos. Res. Lab.), On

the coupled wave equations of magneto-ionic theory. Journal

of Geophysical Research, 58(4) :431 -436, Dec. 19S3. table,

8 refs. , 8 eqs. DLC--The propagation of a plane radio wave

incident vertically on an inhomogeneous ionosphere varying in

the vertical direction in the presence of the terrestrial magnetic field is characterized by a pair of coupled wave equations.

These equations can be changed in appearance by choosing

various different forms for the time factor, coordinate system,

particle charge, and wave functions. In the recent literature,

this has led to some unfortunate confusion, which the present

work is intended to clarify. The wave equations and the basic

defining relations are presented in such a way as to show explicitly the effects of some of the possible arbitrary choices

noted above. A table comparing the present notation with that

used by various other authors is given. --Author's abstract.
203

A-691 Kennelly, A. E. , On the elevation of the electrically conduct - ing strata of the earth's atmosphere. Electrical World and Engineer, N. Y. , 39(11):473, March 15, 1902. DLC--Author

states that waves that are transmitted to distances that are large by comparison with 50 miles, may find an upper reflecting surface in the conducting rarefied strata of the air. If this is correct, the curvature of the earth plays no significant

part in the phenomena. --M.L. R.

A-692 Kessler, Edwin, III (M.I. T. , Cambridge, Mass.), Curvature

corrections for radiowind reports. American Meteorological

Society, Bulletin, 35(7): 328-330, Sept. 1954. 2 figs. , table,

2 refs. , 5 eqs. MH-BH--The errors arising from the neglect of

the curvature of the earth in the reduction of wind data from

modern radio direction finding equipment are discussed briefly.

Data are presented which enable significant corrections to be

made to certain wind reports of interest to the synoptic meteorologist and flight forecaster. --From author's abstract.

A-693 Khakhalin, Viktor Stepanovich, Radiotekhnika v aerologii.

(Radio engineering in aerology. ) Leningrad, Gidrometizdat,

1957. 263 p. 100 figs. , 13 tables, eqs. DWB (M08 K45ra)

--A technical book (3800 copies) with detailed diagrams and

charts for use in teaching and practice in the hydrometeorological service. The basic physical and technological principles of the equipment and propagation are first covered in detail. Ionospheric propagation and modulation are taken up in

Ch. 3, electronic and ionic equipment of all types in Ch. 4,

amplifiers in Ch. 5, radio transmitters of radiosondes and

other aerological equipment in Ch. 6, and other aspects in

the succeeding 7 chapters (power sources, radio location,

thunderstorm cloud and shower location and observations of

other meteorological elements). Radar and cm wave propagation are considered. --M. R.

A-694 Khastgir, S. R. and Das, P.M., Periodic fading of short-wave

radio signals. Physical Society of London, Proceedings, 63-

(ll):924-930, 371B, Nov. 1950. 5 figs. , 7 refs. , 2 eqs. DLC

--Periodic fading patterns recorded photographically on Calcutta signals (4840 kc/s) at 240 km show 3 types: sinuous fading

of quick period, slow periodic fading and the latter with superposed ripples. Physical explanation given. --C. E. P. B.

A-695 Khastgir, S. R. (Wireless Lab. , Dept. of Physics, Banaras

Hindu Univ. ), Abnormal polarization of the atmospheric pulses

reflected successively from the ionosphere. Nature, London,

181(4606) :404-405, Feb. 8, 1958. fig., 3 refs. DWB--During

the determination of the direction of arrival of atmospherics by

the conventional cathode ray tube direction finder the author
204

observed that "on occasions, for atmospherics of comparatively distant origin, there were elliptic patterns of gradually decreasing eccentricity and tilt-angle along with one or more

linear responses, although when tested with the audio-frequency oscillations from a single generator fed into the aerial

system of the cathode-ray tube direction finder, the fluorescent screen exhibited only the usual linear responses. " These

elliptic patterns are considered to be "evidences of polarization of the atmospheric pulses reflected successively from

the ionosphere, the linear responses being due to the direct

(or ground wave) atmospheric pulses. " More than forty oscillograms with elliptic patterns were recorded during the monsoon months of 1955. "A typical record of the processing ellipses with five or six straight lines bunched within a small

angle along with the record of the wave form of the atmospheric pulses simultaneously taken with the automatic atmospheric

recorder" is presented and analyzed. --I. L. D.

A-696 Khastgir, S. R. and Murth, Y.S.N, (both, Dept. of Pure Physics, Univ. College of Science, Calcutta), Left-handed ionospheric echo from an equivalent height of (E + F). Journal of

Scientific and Industrial Research, Sec. B, New Delhi, 18(7):

304-305, July 1959. 3 refs. DWB, DLC--This report reviews

the investigations made by Satyanarayana, Bakhru and Khestgir on the left-hand M echoes as reported in this journal 15B

(1956), 331. It also reviews briefly the right-handed extraordinary M echoes observed by Ratcliffe and White as reported

in the Philo. Mag. 16(1933), 125. It presents an explanation

to the basic fundamentals about these echoes observed from

equivalent heights, with or without the Es echo, and describes

conditions under which the partial reflection and transmission

of such echoes may occur. The rare occurrence of these echoes is due to the off-chance of ion clouds or patches of increased ionization coming in the path of the upgoing wave re- flected from the ground after one reflection from the F-region.

--N.N.

A-697 Kilpatrick, E. L. (Natl. Bureau of Standards, Wash., D.C.),

Polarization measurements of low frequency echoes. Journal

of Geophysical Research, 57(2):221-226, June 1952. 3 figs.,

3 refs. MH-BH--Polarization of a 160 kc plane polarized signal propagated upwards and reflected by the ionosphere at

Sterling, Virginia, October 15-November 30, was characterized by a stable elliptical pattern oriented 60-70 E of magnetic

north, ratio of axes 1/3 to 1/5 and left hand rotation of polar

vector. Short periods of unstable polarization occurred at sunrise, sunset and irregular times. --C. E. P. B.
205

A-698 Kimpara, Atsushi, The waveform of atmospherics at night.

Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 2:1-8, Jan. 1954. 3 figs., 25 plates, 6 refs. DWB--

With a view of investigating the change of wave forms of

sferics with distance, the author discusses the wave forms

observed simultaneously at Toyokawa, Kumamoto and Akita

stations, Japan, in 1952. They are classified into 5 groups

according to the distance: A) more than 4000 km, B) 3-4000

km, C) 2-3000 km, D) 1-2000 km and E) less than 1000 km.

The investigation reveals that in A and B the wave forms depend mainly upon the characteristics of trajectories, in D and

E upon activities in meteorological phenomena and in C upon

both meteorological and propagation conditions. --From author's abstract.

A-699 Kimpara, Atsushi, The sudden ionospheric disturbances on

22 November 1952. Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 2:40-52, Jan. 1954. 11 figs. , 5

tables. Append, p. 48. DWB--Despite the period of lower

solar activity, a striking S.I. D. phenomenon was observed

on Nov. 22, 1952, which revealed the close correlation of

solar flare with outbursts of solar radio waves, Bellinger

fadeout in short-wave communication, characteristic crochets

in three components of magnetograms, fadeout of echoes in

ionospheric measurements, and an abnormal increase of the

intensity of atmospherics at very low frequencies. The author

made a detailed study of these relations and found an advance

increase of the intensity of atmospherics about an hour before

the solar flare. He appends similar results obtained in a more

active period (April, May 1952) as a reference, and discusses

their characteristics and correlations. --Author's abstract.

A-700 Kimpara, Atsushi and Kimura, Yasuko, On field intensity re- cording; of atmospherics at 27 kc/s in accordance with the re- commendation of WMO. Nagoya. Univ. Research Institute of

Atmospherics, Proceedings, 5:21-29, March 1958. 3 figs. , 3

tables, 5 refs. DWB--In order to see if Recommendation 40 of

working group of WMO in 1957 can be applied satisfactorily to

the results obtained in Japan, the authors examined the records

of intensity meters of atmospherics at 27 kc/s observed con- tinuously in 1957 at Toyokawa station. They found fairly regular behaviors of sferics which can be reasonably explained by

the distribution of sources with seasonal variations as well as by the principle of wave propagation. "A" (Sunrise effect) is

found generally 20 min before sunrise, except in winter where

it is found about 2 hrs before sunrise. "B" (First minimum) and

"C" (Recovery effect) are often found more than once, and also

found frequently in the evening. "D" (Morning minimum) is

found about 2 hrs after sunrise, but sometimes not clearly.
206

"E" (Afternoon maximum) is found about 2 hrs before sunset

and sometimes indicates flat maximum. "F" (late minimum) is

found within a half -hour of sunset. "G" (Night maximum) is

not found in Toyokawa. After sunset the field intensity of

sferics increases gradually and reaches night levels about

2^ hrs after sunset, and keeps its level nearly constant till

dawn when "A" is found. "G" should be called "sunset effect"

in Japan. It is due to the difference of distribution of sources

between Europe and Asia. --Authors' abstract.

A-701 Kimpara, A. , Diurnal and seasonal variations in whistler re- cords in Japan. Nagoya Univ. Research Inst, of Atmospherics,

Proceedings, 6, 38, (Jan. 1959).

A-702 Kimpara, Atsushi (Nagoya Univ. , Japan), Perturbations ionospherigues a debut brusque causees par une explosion atomigue . (Sudden ionospheric disturbances caused by atomic ex- plosions. Academie des Sciences, Paris, Comptes rendus,

248:2117-2119, April 6, 1959, 1 fig, 2 refs. DWB, DLC--At

the time of a nuclear explosion at high altitude, meteorological conditions permitted to observe a strengthening of sferics

due to a sudden ionospheric disturbance. The recording of the

sferics was done on 10, 21 and 27 kc/s. Comments on the observations. --A. V.

A-703 King, G.A. M. (Geophysical Observatory, Christchurch, New

Zealand), Relation between virtual and actual heights in the

ionosphere. Journal of Atmospheric and Terrestrial Physics,

London, 11(3/4): 209-222, 1957. 4 figs. , 2 tables, 37 refs.

,

29 eqs. DLC --There are two general methods of deducing the

"true" heights from the virtual height-frequency curve. Aspects

of the comparison method treated are choice of model, effect

of the earth's magnetic field, the meaning of total electron content, and the use of hp and M3000 as height indicators. The

integral method is discussed from the viewpoints of the derived

curve and the step-by-step procedure. There is a brief treatment of the nominal accuracy of reduction, sections on the importance of the earth's magnetic field and on "valleys" between

layers, and a discussion of factors affecting the actual accur- acy of analysis. There are five current research projects at

Christchurch based on true height analysis. The bibliography

is divided up according to subject, and there are notes on the

references. --Author's abstract.

A-704 King, J. W. (Cavendish Lab. , Cambridge), The fading of

radio waves reflected at obligue incidence . Journal of Atmospheric and Terrestrial Physics, London, 12(l):26-33, 1958. 4

figs. , 5 tables, 18 refs. DLC--
207

Previous experimental results on the reflection of radio waves

from the ionosphere at near-vertical incidence have been ex- tended to include the case of waves incident obliquely. It is

shown that the radio diffraction pattern formed at the ground

by a medium frequency wave reflected at oblique incidence is

very much larger than expected and is, on the average, roughly circular. It is concluded that the ionospheric irregularities

responsible for the fading have much greater extent in the horizontal than in the vertical plane. It is found, in general, that

the speed of fading of a wave of frequency 7° is proportional

to /"cos i , where I is the angle of incidence on the ionosphere, and that the probability distribution of amplitude tends to

be log normal rather than of the type discussed by RICE (1947).

--Author's abstract.

A-705 King, J. W. (Cavendish Lab. , Free School Lane, Cambridge),

Ionospheric self-demodulation and self-distortion of radio wav- es. Journal of Atmospheric and Terrestrial Physics, London,

14(l/2):41-49, April 1959. 2 figs., 2 tables, 15 refs. , 9 eqs.

DLC--Experiments in which the phenomenon of ionospheric

self-demodulation was investigated are described. Demodulation is observed to occur only at the lower modulation frequencies, and it is concluded that the occurrences of the phenomenon can be satisfactorily explained by an extension of Bailey's theory of ionospheric cross -modulation as presented by

Huxley and Ratcliffe (1949). The magnitude of the observed

demodulation effect agrees with the value predicted by theoretical considerations and is what would be expected in view of

results obtained in cross -modulation experiments. Complications due to selective fading were not present in the experiments performed. It is found that self-demodulation decreases

as does ordinary cross -modulation, near dawn; this is explained by the fact that the absorption of the radio wave occurs at a level where the collision frequency is of the same order of

magnitude as the equivalent angular frequency of the wave.

--Author's abstract.

A-706 Kirby, Richard C. (Natl. Bur. of Standards, Boulder, Colo. ), Extreme useful range of VHF transmission by scattering; from

the lower ionosphere . Institute of Radio Engineers, N. Y. , IRE

Convention Record, Pt. 1, 1958. p. 112-120. 10 figs. , 15

refs. DLC (IK6541. 15) DWB--Results are given from an ex- perimental study of VHF propagation in the extreme distance

range for scattering from the lower ionosphere. Signal intensity at 36. Mc/s was measured continuously for a year over

the 1411 mile path from St. Johns, Newfoundland, to Terceira

Island, the Azores, using high transmitting and receiving

sites. The median transmission loss is approximately 13 decibels greater than for the same system operated over the 773
208

mile path Cedar Rapids, Iowa, to Sterling, Virginia; this

ratio is interpreted in terms of the geometrical restriction of

the effective scattering volume. Less pronounced diurnal and

seasonal variation is related to occluding by earth curvature

of scattering from heights below about 80 km. Continuous

"height gain" observations give evidence of variation of scattering height diurnally and seasonally. Results are given on

the nature of the signal fading, space-correlation, realizable

gain from arrays having extensive vertical aperture, and polarization effects. --Author's abstract.

A-707 Kirby, Richard C. , 1958 critique of VHF ionospheric scatter

communication. U. S. National Bureau of Standards, NBS Report, 6020, Nov. 10, 1958. 8 p. 11 figs. , 19 refs. DWB

(621. 384 U585ni)--Work at the National Bureau of Standards

reported herein was carried out on behalf of the U. S. Air

Force, Andrews Air Force Base, Washington, D.C. A review

is given of principal research reported in 1957-58, as well as

of several years of operational communication experience us- ing VHF ionospheric scattering for point-to-point radio service.

The developing defined role of ionospheric scattering in military and international communication is discussed, in relation

to other techniques. A survey is given of antenna and modulation developments as well as contributions to basic knowledge

of the propagation mechanism, including new information on

geographical dependence. Frequency requirements are discussed in relation to type of service. --Author's abstract.

A-708 Kitchen, F. A. and Tremellen, K. W. , Ionospheric influence

in television reception. Institution of Electrical Engineers,

Proceedings, Pt. A, 99(18) :290, 1952.

A-709 Kitchen, F. A. ; Pressey, B. G. and Tremellen, K. W. , A re- view of present knowledge of the ionospheric propagation of

very low, low and medium freguency waves, Institution of

Electrical Engineers, Proceedings, Vol. 100, Pt. 3, No. 64:

100- 1953.

A-710 Kitchen, F. A. and Joy, W. R. R. (both. Royal Naval Scientific Service), Some effects of the fine structure of the ionos - phere on transmissions received from the Russian earth satellite 195B/S . Nature. London, 181(4626): 1759-1761, June 28,

1958. 3 figs. , table, 7 refs. DWB--After some simultaneous

direction-finding and Doppler frequency-shift measurements

had been made on the radio transmissions from the Russian

satellite 1958/0 , on a frequency of 20. 005 Mc/s with the initial object of obtaining the parameters of local tracks and those

of the orbit, the authors set up a table for Portsdown, Eng. during the period May 16-22, 1958. Interesting anomalies observed

then are listed. --N.N.
209

A-711 Kitchen, F. A. , Direction finding observations on the 20 Mc/s

transmissions from the artificial earth satellites . Royal Society of London, Proceedings, Vol. 248A, No. 1252:63-68, Oct.

28, 1958. 4 figs. , table, 6 refs. --Several bearing transists

given are discussed relative to ionospheric propagation. Irre- gularities in bearings, strength and Doppler may supplement

ionospheric knowledge if and when detailed orbit data become

available. --W.N.

A-712 Kitchen, F. A. and Johnson, M. A. (both, Royal Naval Scientific Service, London), Role of turbulent scattering in longdistance radio propagation at metre wave-lengths. Nature,

London, 182(4631): 302-304, Aug. 2, 1958. fig., 7 refs. DWB.

A-713 Kitchen, F. A. and Millington, G. , Survey of the Gibraltar

to U. K. ionospheric scatter experiment. Institution of Electrical Engineers, Proceedings, Vol. 105B, Supplement No. 8:2,

1958.

A-714 Knecht, R. W. (Nat'l. Bur. Standards, Boulder, Colo.),

Observations of the ionosphere over the south geographic pole.

Journal of Geophysical Research, Wash., D. C. , 64(9):1243-

1250, Sept. 1959. 5 figs. , 3 tables, 4 refs. DLC-Monthly

median values of penetration frequencies of the ionosphere

over the south geographic pole have been examined. Twenty

months of data (June 1957 through January 1959) are included

in the study of foF2, while foE and foFl median values are shown for 6 summer months (November and December, 1957;

January, November, and December 1958; January 1959). It is

found that F region ionization persists throughout the 6 month

winter night. Marked diurnal variations are observed in the

monthly medians of foF2 even though the usual daily variation

in solar elevation is absent at this unique location. A small

but significant diurnal variation is also found in foFl. In contrast, foE exhibits no regular daily fluctuation, but seems to

depend to a great extent on the level of solar activity. --Author's abstract.

A-715 Kobayashi, Tsuneto (Central Radio Wave Obs. ), Comparison

between the measured and calculated values of the field inten- sities of HF waves in long distance propagation. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 5(4):198-201, 1951. 5 figs. DWB

--Data from observations on Dec. 1950 and during the solar ec- lipse of Sept. 12, 1950 were used for this comparison. The

agreement was fairly good for most cases. --A. A.
210

A-716 Koch, J. W. , Reception of transmitter space diversity signals via England to Soulder, Colorado path. U. S. National

Bureau of Standards, NBS Report, No. 6026, Nov. 26, 1958.

6 p. 4 figs. , table, ref . , 2 eqs. DWB.

A-717 Koch, J. W. , Factors affecting modulation technigues for

VHF scatter systems . IRE Trans, on Comm. Systems CS-7,

No. 2, 77, (June 1959), Institute of Radio Engineers, Transactions, CS-7(2):77-92, June 1959. 24 figs. , 11 refs. , eqs.

A-713 Koch, I. W. ; Harding, W. B. ; and Jansen, R. J. , Fading

rate for propagation research. Electronics, 32(51): 78, Dec.

18, 1959.

A-719 Koch, J. W. , Preliminary study of ionospheric cross -modulation at standard broadcast freguencies. U. S. National Bureau

of Standards, NBS Report, No. 6072, Sept. 25, 1959. 12 p.

2 figs. , 6 refs. , 21 eqs. DWB.

A-720 Koch, J. W. , Reduction of Doppler shift errors in ionospheric

scatter PSK communications. U. S. National Bureau of Standards, NBS Report, No. 6053, May 1, 1959. 8 p. 5 figs. , 7

refs. DWB (621. 384 U535red) -Meteoric Doppler frequency

shifts of signals propagated via ionospheric scattering cause

errors in narrow-band PSK communications. A simple method

of reducing the Doppler-shift errors has been tried. The principle of operation consists of locking out the mark channel

when a space signal is present. The experimental results show

a useful reduction in error rate when the Doppler lock-out circuitry is used. --Author's abstract.

A-721 Koch, J. W. , Study of phase stability for phase-keying applications in VHF ionospheric-scatter communications. U. S.

National Bureau of Standards, NBS Report, No. 6051, April 30,

1959. 8 p. 7 figs., 2 refs. DWB (621. 384 U585stud)--A

study of phase stability of the ionospheric-scatter propagation

medium has been carried out, with the objective of determining the usefulness of phase-shift keying systems for communication by this mode. Observations of 20 millisecond integrated phase perturbations and instantaneous phase perturbations

were made at frequencies of 30 and 50 megacycles per second.

Results of the measurements program indicated that integrated

phase variations over 20 millisecond periods were quite large

for an appreciable percentage of the time, and that the ionospheric scatter mode is not suitable for systems requiring phase

stability for such periods. Data for the instantaneous phase

variations were analyzed by determining the phase perturbations

between 5 millisecond sampling points. These data were not of

sufficient quantity to draw any definite conclusions, but did
211

point up the need for more instantaneous phase measurements

that can be resolved for sampling points separated by 2 milliseconds or less. The instantaneous phase perturbation data

did tend to indicate that a system requiring phase stability for

somewhat less than 5 milliseconds might be useful. --Author's

abstract.

A-722 Kodaira, N. and Inaba, M. , On the inherent errors of the

rawin set. Tateno, Japan. Aerological Observatory, Journal,

5(l):l-5, March 1951. figs., eqs. English summary p. 1.

DWB--Short discussion of the angular errors due to the rawin

set itself, due to wave propagation and due to the misreading

of the indicator in the case of very strong fading. --A. A.

A-723 Koenig, H. , Atmospherics geringster Freguenzen. (Spherics

at the lowest frequencies. ) Zeitschrift fur Angewandte Physik,

ll(7):264-274, July 1959. 11 figs. , 25 refs.

A-724 Kojan, J. S. and Isted, G. A. , The first ionospheric storm

warning service. Marconi's Review, 13(97):53-71, 1950. 14

figs. DBS—Purpose of this article is to state the reasons why

ionospheric storm warning system was necessary during the war. After briefly describing the ionosphere authors analyze

the effects produced on high frequency communication and direction finding system. Improvements made after establishing

the Inter-Services Ionosphere Bureau in 1941 as well as efficiency of storm warning issued from Barrow and the new development are discussed. --W. N.

A-725 Komesaroff, M. M. and Shain, C. A. , Refraction of extra - terrestrial radio waves in the ionosphere. Nature, London,

183(4675) = 1584-1585, June 6, 1959. fig., 5 refs. , 3 eqs.

DLC--New expressions derived for refraction, taking into ac- count the effects of horizontal gradients in electron density

and considering the magnitude of the uncertainties involved

in the necessary approximations are demonstrated. The analysis is restricted to the case of a transit radio telescope. The

astronomical value of the ionospheric refraction corrections,

the observed and corrected positions are indicated graphically.

--From authors' text.

A-726 Koster, J. R. and Storey, L. R. O. , An attempt to observe

whistling atmospherics near the magnetic eguator . Nature,

London, 175(4444) :36-37, Jan. 1, 1955. 5 refs. DWB--According to the theory of T. H. BARKHAUSEN and T. L. ECKERSLEY,

whistlers are due to dispersion in the ionosphere of "clicks"

radiated by lightning strokes, and should not occur near geomagnetic equator. At Achimota, Gold Coast, no whistlers

were detected in 3 years (about 15 hours observation) though
212

they occurred 1-3 times a minute during the same period in

England. --C.E. P. B.

A-727 Kotadia, K. M. , Sporadic echoes from the E region over

Ahmedabad (23°02'NT 72^38 'E) . Journal of Atmospheric and

Terrestrial Physics, London, 8(6):331-337# June 1956. 9 figs.,

2 tables, 8 refs. DWB--In this paper, a study is made of the

sporadic E echoes observed in the ionospheric h'-f records of

Ahmedabad ( c|) = 13. S N). From the analysis of the data for

1953-1954, a sunspot minimum period, it was found that three

types of sporadic, namely: 1) Esc at 95-100 km, 2) Esn at 105-

125 km, and 3) Ess at 115-125 km, occur in the E region. The

overall bahavior of Es has been shown as being due to the combination of the characteristics of these three types. The sporadic ionization of type Esc has a maximum frequency of occurrence in the late evening hours, and has a thin structure. It is

apparently evolved out of a downward drift of the residual ionization of the normal E layer. No correlation could be established with meteor activity. Esn shows a minimum in the afternoon and maximum in late night hours before dawn. Ess is developed by the vertical downward movement of the E2 layer.

--Author's abstract.

A-728 Krasovskii, V. I. , Sovetskie issledovaniia ionosfery pri pomoshchi raket i iskusstvennykh sputnikov Zemli. (Soviet ex- ploration of the ionosphere by rockets and artificial earth satellites. ) Iskusstvennye Sputniki Zemli, Moscow, ISjo. 2:36-49,

1958. 15 figs. , 15 refs. , 4 eqs. DLC--A review of the principle studies in the ionosphere by means of rockets and artificial earth satellites carried out in the U. S. S. R. The methods

for making these studies involved the use of the disperse interferometer which measured the radio waves radiated from the

rocket and the satellite, and the direct measurement of the concentration of charged particles in the ionosphere, and the trans

mission of the reading by telemetric systems. The apparatus

are described with the aid of diagrams and photographs and the

results of individual rocket and satellite ascents are presented

in graphs. The ionization above the maximum of the F2 layer

declines very slowly with height so that the altitude scale for

ionizing particles is very large; at 475 km an ionization of

about 10" electrons mets/cm^ was recorded on Feb. 21, 1958;

at 795 km the concentration of positive ions reached 1. 9 x 10^

ion/cm^ on May 15, 1958. The effective temperature of electrons in the F region and above was higher than the temperature

of the environment. The ionosphere below the maximum of the

F region, in contrast to its model, constructed on the basis of

ionospheric probing from the earth, does not have sharply demarcated layers but is characterized by a small maxima with

nonatomic increase in electron density up to the maximum of
213

the F2 layer. The maximum of the F2 layer, and in general

the ionization below this region, is 50 - 150 km below the

values of the usual ionospheric probing from the earth. The

equations for computing the mean electron density at a given

elevation, the current of the collector in the direct determination of ion concentration, and the deceleration potential are presented in appendices. --I. L.D.

A-729 Krassovskii, V. I. , Exploration of the upper atmosphere with

the help of the third Soviet sputnik. Institute of Radio Engineers, Proceedings, 47(2): 289 -295, Feb. 1959. 10 figs.

A-730 Kraus, Lester and Watson, Kenneth, M. , Plasma motions in - duced by satellites in the ionosphere. Physics of Fluids,

N. Y. , l(6):480-488, Nov. /Dec. 1958. DWB»The electrohydrodynamic phenomena associated with the high velocity motion

of a charged body in a plasma are investigated with a view to

applications to satellite motion in the ionosphere. It is shown

that the effect of the electric field due to the charge on the

body in inducing collective motion leads to similar results

both for high- and low-density gases. By using a linearized

theory, formulas are obtained for the electrohydrodynamic drag

and for the increased ionization in the Mach cone behind the

body. --Author's abstract.

A-731 Krautkramer, Josef (Ko'ln University, Institute of Theoretical

Physics), Uber Wanderungserscheinungen rascher Feldstffrke - Schwankungen von Ionosphcitren- Echos . (Drift phenomena for

rapid fluctuations of field strength of ionosphere echoes.

)

Archiv der Elektrischen Ubertragung, 4:133-138, April 1950.

19 figs., 3 tables, 14 refs. DLC--Three receivers placed in a right angled pattern made possible measurements of magnitude and direction of the travelling speed along the earth's sur- face of the field strength variation of ionospheric echoes. The

observed interference line system can be interpreted as some

inhomogeneity in the ionospheric layers that travel about 100

m/s with a frequency maximum between 80 - 100 m/sec. West

direction is characteristic for the E layer; uncertain for the Flayer. The temporary results are given in table and graphs and

are briefly discussed. --W.lM.

A-732 Krishnamurthi, M. ; Sastry, G. Sivarama and Rao, T. Seshagiri (all, Physical Laboratories, Osmania Univ. Hyderabad),

Abnormal ionospheric behaviour at 10 metres wavelength.

Current Science, Bangalore, 27(9): 332 -333, Sept. 1958. fig.,

table, ref. DLC--The radiation intensity of 10 m cosmic radio

waves fell to zero on Jan. 28, -Feb. 21, and March 2, 1958 at

the Physical Laboratories, Osmania University, Hyderabad,

India (17°26'N, 78°27'E). The gradual fall of intensity occured
214

about sunrise time, and the rise of intensity toward end of the

phenomenon was uniformly rapid in the three cases, but differed in duration of minimum noise level. Small scale irregularity in the upper ionospheric layers is offered as a plausible

cause of this disturbance which is knowingly unrelated to any

solar flare. --W. N.

A-733 Kundu, M. R. , Velocity of movement of sporadic E clouds . Calcutta. Univ. Institute of Radio Physics, Research Report,

7:23-25, 1954/1955, pub. 1955. fig. , 2 refs. DWB. Also

in Science and Culture, Calcutta, 20(6):303, Dec. 1954. --The

height distribution of ionization in the composite F region is

calculated on the assumptions that the scale height (i. e. , the

temperature) increases and the recombination coefficient decreases with height in this region. The recombination coefficient is assumed to vary in terms of the reduced height, that

is, the height (above Fimay) measured in terms of the scale

height and not in terms of the actual height as had been done

earlier by A. P. Nitra in making similar calculations. The

present assumption automatically takes into account the effect

of rising temperature on the value of the recombination coefficient. Height distribution curves for high and low latitude

stations are drawn for typical summer and winter conditions in

the high atmosphere in the F region. It is found that when the

possible effects of ionospheric tidal drifts are taken into ac- count, the forms of the distribution curves, as also the separation between the Fl and F2 layers, agree with those deduced

from observational data. The investigation lends support to

the hypothesis that the ionospheric regions Fl and E2 belong

to a common bank of ionization produced by a common ionizing

radiation from the sun. --Author's abstract.

A-734 Deleted*

A-735 Laby, T. H. ; Nicholls, F. G. ; Nickson, A. F. B. et al.

,

Reflection of atmospherics at an ionized layer. Nature, London, 139(3524): 837-838, May 15, 1937. figs., table, 6 refs.

,

eqs. DLC- -Hundreds of sferic wave forms were analyzed.

More than twenty showed pulses seemingly reflected from 78-

82 km above the earth. Intervals of time, distance of flash

and height of layer were calculated. The fundamental frequency of the sferic pulse was 10^ cycles/sec in which case re- flection occurs when ionization reaches 1 electron per cnW. -- W.N.
215

A-736 Laby, T. H. , Mcfceill, J. J. , Nicholls, F. G. and Nickson,

A. F. B. , Wave form, energy and reflexion by the ionosphere

of atmospherics. Royal Society of London, Proceedings, Ser.

A, 174(957): 145-133, Feb. 1, 1940. DLC--Work was begun in

the study of the wave form of sferics by physicists of the Radio Research Board of Australia in 1935. Evidence that atmospherics are reflected by the ionosphere was obtained in 1937.

This article summarizes systematically the work done and re- ported in earlier papers, including a description and illustration of equipment, ray theory of reflection at the ionosphere,

calculation of oscillograms, relation between field strength

and distance of source, energy and speed. Atmospherics were

recorded from sources 70 to 1500 km distant and paths both direct and reflected from ionosphere were calculated. From the

time interval (distance on photographic record) between direct

and reflected impulse, the height of reflecting layer and distance of source can be calculated. Heights lie between 53

and 82 km. Relation between distance and field strength is

x linear. --M. R.

A-737 Landmark, Bj0rn, Polarization of radio waves reflected from

the ionosphere. Journal of Atmospheric and Terrestrial Physics, 2(4):254-255, 1952. 3 figs. MH-BH, DWB--The z-component of radio waves at Tromso7 was found to be polarized in

the same way as the ordinary component. Positive correlation

was found between axis ratio of polarization ellipse and absorption index. Axis ratio varied markedly during polar magnetic storms and discontinuities. --C.E. P. B.

A-738 Landmark, Bjorn, A study of the limiting polarization of high

frequency radio waves reflected vertically from the ionosphere.

Geofysiske Publikasjoner, Oslo, 19(7), 1955. 46 p. figs.,

33refs., eqs. Price: Kr. 10.00. DWB, DLC -Polarization

measurements made both at Kjeller and at Troms^ are reported

and the experimental equipment is described. Twenty observations of the sense of polarization (sense of rotation of the

field vectors) of the magneto-ionic third component, the z-component, all show that this component is polarized in the same

way as the ordinary magneto-ionic component. This is in ac- cordance with present theories which explain the z-component

by a coupling mechanism. During quiet conditions the reflected waves both at Kjeller and at Troms^, were found to be in

general nearly circularly polarized as should be expected ac- cording to a full wave theory. However, departures from circularity were observed; these are explained by a statistical

theory of limiting polarization developed in this paper, in

which the reflected wave is treated as a sum of rays reflected

within a cone about the vertical direction, the phases of the

individual rays being distributed at random. On the basis of
216

this theory effects on the limiting polarization of horizontal

gradients and irregularities may be accounted for. Conditions

under which departures from circularity were most frequently

observed are described. --From author's abstract.

A-739 Landmark, Bj^rn, Measurements of limiting polarization of

r adio waves reflected from the F-layer. Journal of Atmospheric

and Terrestrial Physics, 6(5):284-286, May 1955. 2 figs. , table, 5 refs. DWB--The radius vector, vector angle and axis

ratio of F-echoes were recorded at Kjeller, Oslo, to test MORGAN'S observation that echoes become nearly linearly polarized when the critical frequency is approached. No correlation was found between magnitude of group retardation and

state of polarization. The axis ratio was 0. 8 to 1. compared

with MORGAN'S 0. 1 - 0. 2. -C. E. P. B.

A-740 Landmark, B. and Lied, F. , Note on a "QL-QT" transition

level in the ionosphere. Journal of Atmospheric and Terrestrial Physics, 10(2): 114-116, Feb. 1957. 3 figs. , 2 refs.

DWB-Referring to article by D. LEPECHINSKY (Ibid. , 8(6):

297-304, June 1956; see 7. 11-161, Nov. 1956, MAB), authors

point out that at Tromso7 there is no transition level associated

with an abrupt change of refractive index. A method is outlined by which information may be obtained of electron density

between E and F layers. At Tromso' there was no marked decrease in electron density. --C. E. P. B.

A-741 Landmark, B. , The fading of radio waves reflected from the E- layer. Journal of Atmospheric and Terrestrial Physics, 10(5/6):

288-295, 1957. 10 figs. , 7 refs. , 5 eqs. DWB-The amplitude

and phase of waves of frequency 2 Mc/s reflected vertically

from the E layer were studied. It was found that there were re- gions in the wave pattern, of extent D, at the centre of which

the phase-path exceeded that at the edges by ^, P. When ^ P/

D 0. 025 approximately, the variations of amplitude and phase

were associated as they would be if the phase variation was

caused by a concavity in the reflecting layer. There resulted

a "burst" of amplitude caused by focusing, inside which there

was comparatively rapid fading. When P/D > 0. 025, the

conditions became more complicated, but on one occasion

could still be analyzed in terms of a moving concavity in the

layer. Observations made at night on waves of frequency 200

kc/s reflected at an angle of incidence of about 40 were ex- plicable in terms of the same model. --Author's abstract.

A-742 Landmark, B. (ed. ), Papers presented at the Ionospheric Research Meeting AGARD Avionics Panel. Cambridge. England.

AGARDograph, Paris, No. 34, Sept. 1958. 204 p. figs.,

photos, tables, refs. , eqs. throughout. Pertinent articles
217

abstracted separately. At head of t-p. : North Atlantic Treaty

Organization, Advisory Group for Aeronautical Research and

Development (AGARD). DWB (629. 1323 h 864a) -A collection

of 16 papers dealing with different aspects of sporadic E ionization presented at the meeting and the introductory and final

remarks by J. A. Ratcliffe of Cavendish Laboratory, Cambridge,

England. The papers are arranged here in six parts with a summary discussion at the end of each part. In his initial remarks

J. A. RATCLIFFE emphasized the general need for clarity in

the discussions. For this purpose he expressly suggested to

use classification only to simplify, to discuss theories which

can be tested experimentally, and not to pay too much attention to the precise shape of the E-layer. In his final remarks

he highlighted the main points which arose during discussions.

--I.S.

A-743 Lange-Hesse, Gi^nther, Analyse beobachteter Absorptions

schwankunqen elektromagnetischer Wellen in der Ionosphare.

(Analysis of observed variations of absorption of electromagnetic waves in the ionosphere.) Naturwissenschaften, 39(13):

297-298, July 1952. 5 refs. DWB--A calculation of the absorption factor for short waves (10-200 m or 30-1. 5 MHz) shows

that transmission is possible throughout the year near the equator, but in middle latitudes only in summer, when it can be

forecast from sunspot number and 27-day cycle. In the auroral

zone it is correlated with magnetic disturbances. --C.E. P. B.

A-744 Lange-Hesse, Gunther (Gdfttingen), Verqleich der Doppel- brechuno; im Kristall und in der Ionosphare . (Comparison of

the double refraction in crystals and in the ionosphere.

)

Archiv der Elektrischen Ubertragung, Wiesbaden, 6(4): 149-

158, April 1952. 8 figs. , 14 refs. , 44 eqs. DLC--The double

refraction of light by crystals and of electromagnetic waves in

the ionosphere show analogous features from a formal point of

view. The geomagnetic field produces electrical anisotropy

in the ionosphere. The dielectric constants of the ionosphere

are derived. The causes for the difference between double re- fraction phenomena in both media are discussed in detail. The

formal mathematical discussion is compared with observation

results. Polarization is briefly discussed. --A. A.

A-745 Larenz, R. W. , Zur Doppelbrechunq der Ionosphare. (On

double refraction in the ionosphere. ) Naturwissenschaften,

40(20):527, Oct. 1953. 5 figs. , 3 refs. , eq. DWB»The two

refraction indexes n of electromagnetic waves for an electron

plasma in a magnetic field are calculated for magnetic field

parallel to wave propagation and at an angle with infinite and

finite conductivity and for different electron pressures. The

mathematical difficulties are discussed. --C.E. P.B.
218

A-745 LaTourette, P. M. , Reduction and processing of F-layer propagation data. Stanford University, Electronics Research Laboratories, Contract AF 19(604) -1830, Report No. 4, Dec. 1958.

A-747 Laursen, Veggo (corap. ), Bibliography for the Second International Polar Year. 1932-33. Copenhagen, I, M. O. Temporary

Committee on the Liquidation of the Polar Year, 1932-33, 1951.

253 p. DWB--The references are arranged according to countries and according to main subjects. In the section on Radioelectricity (p. 236-241) will be found 80 references, many dealing with the subject of ionospheric propagation. --M. L. R.

A-748 Lauter, Ernst August, Zur Statistik der nachtlichen abnormalen

E-Schicht. (On statistics of the abnormal nocturnal E-layer. ) Zeitschrift fur Meteorologie, 4(7-8): 234-240, July-Aug. 1950.

4 figs. , 8 refs. MH-BH--Sudden increases of ionization in Elayer were investigated through the ratio Bg (space wave/-

ground wave) for 1250 m. Potsdam transmission. Daily values of magnetic disturbance K and Bg are plotted in 27-day

periods Nov. 1947 - May 1950. Minimum BE follows 3 days

after maximum K. In 14/73 cases no marked absorption followed maximum K but there was a secondary maximum K instead. Five cases are examined specially, including high

level radiation. Observations show that ionization must be

due to solar corpuscular charged radiation of 200-300 km/sec. , penetrating below 100 km. --C. E. P. B.

A-749 Lauter, Ernst August and Sprenger, K. , Nachtliche Ionisationsst6rungen der tiefen Ionosphare. (Nocturnal ionization

disturbances of the lower ionosphere. ) Zeitschrift fur Meteorologie, 6(6):161-173, June 1952. 19 figs. , 20 refs. MH-BH

--On the basis of almost 4 years of continuous record of nocturnal space radiation at 245 kHz registered with a frame an- tenna at approximately 55 N lat (54 geomagnetic lat. ) four

types of ionization disturbances in the E layer are described.

These are the P-type (very rapid polarization variations without noticeable decline of reflection coefficient), S-type (storm

type), A-type absorption nocturnal E reflections begin after

sunset) and B-type (Bay disturbances). The relationships between these disturbances and terrestrial magnetic disturbances

are analyzed statistically but cannot be explained by the ac- cepted model of the ionospheric and terrestrial magnetic cor- puscular disturbances. The possibility of ionospheric observations in the long wave region providing an explanation of

the disturbances in the E layer and also an explanation of the

relationship between atmospheric winds and these disturbances

is suggested. --I. L.D.
219

A-750 Lauter, E. A. , Variationen der D-Schichtdampfung auf 245

kHz. (Variations of D layer damping on 245 kHz. ) Zeitschrift fur Meteorologie, 7(ll):321-330, Nov. 1953. 18 figs. , 19 refs. MH-BH--Results of the measurement of reflection

coefficient on 245 kHz during midday and in the evening are communicated. The diurnal and auroral course of the damping

is shown, and the data with other frequencies compared. The

damping values of the D layer have a close relationship to atmospherics and a weak one to geomagnetic activity. A 24-day

recurrence tendency is clearly indicated. The midday values

of the damping are 2 nepers in the winter and almost 7 nepers

in the summer. --A. A.

A-751 Lauter, E. A. , Der atmospharische Stcrpeqel im LSnqstwellenbereich und seine tages- und jahreszeitlichen Variationen.

(The atmospheric noise level in the longest wave region and

its diurnal and annual variations. ) Zeitschrift fur Meteorologie, Berlin, 10(4):110-121, April 1956. 12 figs. , 11 refs.

DLC --Problems of the definition and measurement of the noise

level are discussed from measurements of dependence on frequency, and statistics, of atmospherics. The dependence of

the noise level on ionospheric conditions and on the frequency

and position of centers of disturbance is shown from 3-year

mean monthly diurnal variations on 14, 27 and 48 kHz. This

shows that in winter the distribution conditions depend especially on the diurnal variation, but in summer on the approach

of disturbance centers. Some remarks are added on geophysical peculiarities in the recording of atmospheric disturbances,

such as interdiurnal variability, twilight effect and solar flare

effect. --Trans, of author's abstract.

A-752 Lawrence, Robert S. (Nat'l. Bureau of Standards, 3oulder,

Colo. ), An investigation of the perturbations imposed upon

radio waves penetrating the ionosphere . Institute of Radio

Engineers, N. Y. , Proceedings, 46(l):315-320, Jan. 1958.

4 figs. , 38 refs. DLC--A new method has been devised to

measure continuously the phase deviations introduced by the

ionosphere into the signals from discrete sources. Sample

recordings of measurements at frequencies of 53, 108, and

470 mc are given. An experiment combining this phase measuring technique and standard ionospheric soundings at the

point of penetration of the line of sight is in progress and is

expected to shed light upon the height of origin of ionospheric

scintillations. --Author's abstract.
220

A-753 Leadabrand, R. L. ; Dolphin, L. and Peterson, A. M. , Upper

atmosphere clutter research: Part I: Experimental Radars for

Radio Propagation Studies. Part II: Preliminary results of 400

mc radar investigations of auroral echoes at College, Alaska.

Part HI: Preliminary results of radar investigations of meteor

echoes at 100 and 400 mc. Stanford University, Electronics

Research Laboratories, Contract AF 30(602)-1462, Technical

Report Pt. I, II, III, Oct.

A-754 Leithaser, G. and Beckmann, B. , Uber Beziehungen der Ion- ospharenschichten zu meteorologischen Einflflssen. (Correlation between the ionospheric layers and meteorological influences. ) Zeitschrift fur Technische Physik, Leipzig, 18:59-61,

1937. DLC--The nocturnal elevation of the ionospheric layers

is discussed in relation to upper air winds. Steepness of the

layers as influenced by intensity of the E-W winds are shown

in curves for Jan. -Aug. and Oct. 1936. The radio echo curve

is mentioned briefly. --W. N.

A-755 Lejay, Pierre and Durand, J. , Sur une explication probable de

certain echos ionospheriques fortement retardes. (A probable

explanation of certain markedly delayed ionospheric echoes. ) Academie des Sciences, Paris, Comptes Rendus, 230(6):493-

495, Feb. 6, 1950. DLC--An attempt to explain these echoes

by oblique reflection. --W. N.

A-756 Lejay, Pierre, Methodes modernes de recherches sur la haute

atmosphere. (Modern methods of research on the upper atmosphere. ) Conference at the Palais de La Decouverte, Jan. 16,

1954. Paris, 1954. 25 p. 5 figs. Conferences de la Decouverte, Ser. A. , no. 192. DLC --Spectroscopic rocket (direct

measurement) and radio echo methods of upper atmospheric re- search are described, and results in terms of temperature (to

150 km), density, winds, ionization, chemical composition,

oscillations and radio propagation conditions discussed in this

pamphlet. --M. R.

A-757 Lejay, Pierre; Pillet, Genevieve and Chezlemas, Rene, Mesure de 1' absorption non deviative des ondes radioelectriques

dans V ionosphere. (Measurement of non deviative absorption

of radio-electric waves in the ionosphere. ) Academie des Sciences, Paris, Comptes Rendus, 240(18): 1745-1748, May 2,

1955. 3 figs. , 2 refs. DLC--A method of ionospheric recording is described which eliminates errors affecting methods involving double echoes. Median values of absorption obtained

at Demont (France) in Dec. 1954 and Jan. 1955 for every hour

of the day are graphically presented. If the exponential law

(cos X)n is assumed for the variation of absorption (J3T = zenith angle of the sun, 0. 3 is obtained as the approximate value
221

of n, which is close to the value found by Davies and Hagg

(1955) for the same period at a higher latitude. --G.T.

A-758 Lejay, P. , La mesure des vents ionospheriques. (Measurement of ionospheric winds. ) Academie des Sciences, Paris,

Comptes Rendus, 245(3): 253-257, July 17, 1957. 4 refs.

DLC--Measurement of ionospheric winds based on the method

of three receivers (Demont) is given. Three antennae have

been erected at the summits of a right angled triangle, the

small sides of which develop a length of about 200 m and are oriented nearly North-South and East-West. The three receivers magnify the echoes, received after reflection on the ionosphere, of the signals of an impulse emitter (1 KW crest,

settled on 3, 4 MHz adjoining the receivers. The recorded

electronic displacements could possibly be explained to be

in relationship with the electrical streams susceptible to

clear the diurnal changes of the earth's magnetic field. It seems, however, that a wave dephasing of 2 to 3 hours should

exist in the way of an advance of the registered directions on

the directions forecast by the magneticians. The author points

out that seasonal change of ionospheric wind directions does

not exist. --A. V.

A-759 Lepechinsky, Dimitri, L 'influence sur les enreqistrements de

sondaqes ionospheriques de la couche E, du niveau de separation des regions de propagation quasi lonqitudinale (Q.L.

)

et quasi transversale (Q. T. ). ( Effect of the height of the

boundary surface between regions of quasi -longitudinal and

quasi-transversal propagation on records of ionospheric soundings for the E-layer.) Academie des Sciences, Paris, Comptes

Rendus, 241(4) :897-900, Oct. 3, 1955. 3 figs. , ref . , 3 eqs.

DLC --Sample records show the characteristic discontinuties,

and the underlying theory and assumptions are discussed. -- A. A.

A-760 Lepechinsky, D. , Ionosphere. (Commission III, XII

Assemblee Gen6rale de 1 'Union Radio Scientifique Internationale. (Ionosphere (Report of Commission III, Xllth General Assembly of the International Scientific Radio Union.) L'onde

Electrique. Paris, 38(376) :514-526, July 1958. 3 figs. , 67

refs. DLC --Report of work done by members of Commission

III at the Xllth general assembly of the International Scientific

Radio Union. Regarding the lower ionosphere, the author ex- amines the main ideas of the complete statement of results of

Prof. Waynick's researches in this field (experimental data - probable constitution of the layer, lower E region. The important question of ionospheric diffusion which was the object

of a special meeting, was submitted by G. H. Booker. A cer- tain number of experimental results were mentioned by various
222

speakers on meteoric and auroral reflections and on the turbulence in the ionosphere. The results of available observations, relating to solar and geophysical phenomena of Feb. 23,

1956 (chromospheric eruption) were set forth by various speakers. A-761 Lepechinsky, D. (Lab. Nat'l. Radioelectricite, Paris), De

l'oriqine des echoes E sporadique: quelques donnees experimentales recueillies en France. (On the origin of sporadic E

echoes; some experimental data obtained in France. ) AGARDograph, Paris, No. 34:97-107, Sept. 1958. fig. , table, 10

refs. French summary p. 97, English summary p. 108-109.

DWB (629. 1323 N864a) --Some experimental data gathered in

France are cited as confirming Gallet's "Synamic" theory of

the sporadic echo phenomenon. The correlation observed between the variability of ionospheric winds and the occurrence

of transparent Es echoes as well as the obvious lack of cor- relation between the Es recorded simultaneously at Bagneux

and Poitiers during the 12 months of 1957 support the hypothesis of purely dynamic origin of Es echoes. Accordingly, the

Es echoes arise from the turbulence of ionization at high altitudes rather than from a particular ionizing agent. The most

frequently observed types of Es in the 10 ionospheric sounding

stations attached to the C.N. E. T. are also tabulated. --L S.

A-762 Lepechinsky, Dimitri and Davoust, Claude, Quelques effets

d'explosions nucleaires surles sondages ionospheriques verti - caux. (Some effects of nuclear explosions on vertical ionospheric soundings.) Academie des Sciences, Paris, Comptes

Rendus, 248(8): 1203-1206, Feb. 23, 1959. 2 tables, reL

DWB, DLC --Study of ionograms recorded at Tahiti on Aug. 1,

1958 and of those recorded at Maui (Hawaiian Islands) and at

Rarotonga (Pacific) on Aug. 12, 1958 when explosions of atom

bombs were scheduled in the Pacific Ocean. This study gives

evidence of a very abnormal absorption. This ionospheric effect due to atomic explosions can be explained through the intense warming up of the lower ionosphere, causing an increased absorption going as far as "black-out" in the regions at less

than 1000 km from Johnston Island. The radius of "ionospheric

influence" of the atomic explosions seems to have reached

about 3500 kms for the bomb of Aug. 1 and about 5000 kms for

the bomb of Aug. 12. -A. V.

A-763 Liakhov, B. (Res. Inst, of Geomagnetism, Ionos. and Radio

Propagation, USSR), Work done according to IGY programme. Indian Journal of Meteorology and Geophysics, New Delhi,

10(l):67-68, Jan. 1959. DWB, DLC-During the I. G. Y. , the

Research Institute of Geomagnetism, Ionosphere and Radio

Propagation of the USSR Ministry of Communications, the
223

Radio Engineering and Electronics Institute of the USSR Academy of Sciences and other research bodies have studied the

structure of the ionosphere, made significant calculations by

large electronic computing machines, analyzed the moments

of the appearance and disappearance of the radio signals from

the outer ionosphere, as well as that of the concentrated electrons at altitudes of 600-700 km. It is concluded that the limit

of the atmosphere is at 2000-3000 km. There has been an abundant exchange of scientific materials on solar activity, the

ionosphere and the condition of earth's magnetic field which

has proven of value for short-range magnetic and ionospheric

forecasting. The Soviet also established a magnetoionospheric

station at the pole of homogeneous magnetization at station

Vostok in the Antarctica (lat. 78. 5°S; long. 111°E) at an altitude of over 3800 m, nearly 1500 km from the coast. --N.N.

A-764 Lien, J. R. ; Marcou, R. J. ; Ulwick, J. C. ; Aarons, J. and

McMorrow, D. R. , Ionosphere research with rocket-borne instruments. (In: Boyd, R.L.F. ; Seaton, M.J. and Massey,

H. S. W. (eds), Rocket exploration of the upper atmosphere.

London, Pergamon, 1954. p. 223-239. 17 figs. , table, 14

refs. , 6 eqs. ) DWB--Measurements of effective electron density, collisional frequency, and propagation modes over a long

path have been made by a series of U. S. A. F. rocket flights at

White Sands Proving Ground and Holloman Air Development

Center, New Mexico. Data on effective electron density have

been obtained by measuring the retardation time of a radio signal a megacycle or so above the critical frequency for the Eregion. The retardation times were found by comparing the

time of arrival in the rocket of two synchronized signals sent

from the ground, one of which is the probing signal and the

other an ultra-high frequency reference signal that suffers negligible retardation. On several occasions a profile curve re- lating the effective electron density vs. altitude has been obtained for the regions between 90 and 130 km. These data show

the E region to be bifurcated with a separation between layers

of about 15 km. This gives support to the view that at least

two ionization processes exist within the E region. Some knowledge has been gained of the possible modes of propagation

over a long path. Pulsed signals sent from the National Bureau

of Standards transmitter at Sterling, Virginia, are received both

on the ground and in the rocket near the White Sands region,

New Mexico. The signals received in the rocket are retransmitted to the ground, where they are recorded together with

the ground received signals. It has been possible to follow

the variations in propagation modes as the rocket makes its

ascent. In order to obtain a more precise determination of the

collisional frequency in the lower E region, a rocket experiment is proposed using the "Luxembourg" or cross modulation
224

phenomenon. The experiment yields the product with re- spect to altitude. When combined with the "retardation" ex- periment, it is possible, in principle, to obtain the factor G

itself. --Authors' abstract.

A-755 Lindquist, Rune, The panoramic ionospheric recorder. Tellus,

l(4):37-43, Nov. 1948. 12 figs. , 8 refs. Abstract p. 35.

DWB--A new type ionospheric recorder was installed at the

Askim Observatory near Gothenburg, Sweden in July 1948. The

recorder, oscillator, transmitter, antenna system, receiver,

relay, time-base indicator and records are described and illustrated. Five sample records are reproduced, showing varying

degrees of disturbances. Very good records are obtained in

polar regions which are subject to great fluctuations in height

and stability of ionospheric layers, because of short sweep

time.--M. R.

A-766 Lindquist, Rune A. , A survey of recent ionospheric measurements at the Ionospheric and Radio Wave Propagation Observa- tory at Kiruna. Arkiv for Geofysik, Stockholm, 1(2-4) :247-266,

1951. 28 figs. , 10 refs. MH-BH--Ionospheric research started at the Ionospheric and Radio Wave Propagation Observatory

at Kiruna on Oct. 1, 1948. This report gives some preliminary results obtained from the recordings during the period October 1948-August 1949. Different types of sporadic E echoes

are classified and the diurnal and seasonal behaviour of Es is

shown and discussed. The relation between E's and magnetic

disturbances is further discussed. A few typical polar blackouts are described and studied. The diurnal and seasonal behaviour of the ordinary layers is also shown as a final bi -product. --Author's abstract.

A-767 Lindquist, Rune (Pa. St. Coll. Ionosphere Res. Lab. ), Inter- pretation of vertical incidence equivalent height versus time

recordings on 150 Kc/s. Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122)-44, Ionospheric Research, Scientific Report, No. 33, June 10, 1952.

115 p. 27 figs. , tables, 20 refs. DWB--Results of measurements during (disturbed and undisturbed days) Jan. 1950-March

1952 are tabulated, monthly median heights computed and presented in graphs that are discussed. The normal behavior of

the bottom of the E layer is discussed and some conclusions

as to the conditions within the layer and immediately above

are given. The coupling echo does exist. One echo form, re- gular during magnetic disturbed nights, is due to one type of

sporadic E. Group and phase heights are compared and the

difference checked against theoretical predictions. Results of

the effect of solar flares are given. --W. N.
225

A-768 Linford, Leon B. , Physical properties of the upper atmosphere . Utah, University, Progress Report No. 3, Nov. 24, 1950. 22

p. 7 figs. (Contract AMC No. W19-122 ac 15. ) DWB-Most

of the report is concerned with the design of circuits and modifiers for wide-deviation reaction-tube modulator equipment for

use in studying transmission constants of electro-magnetic

waves in the optical, 10-cm. , 500-Mc, 18-Mc and 4. 5-Mc

bands; and dispersion curves with band widths of 2-Mc centered at 18-Mc and 4. 5-Mc. Previously the maximum deviation at 2-Mc was 7. 5% swing. On this project swings as high

as 71% were obtained. --M. R.

A-769 Little, A. S. , Hourly measurements of ionospheric characteristics, Macauarie Island, 1953. Australian National Antarctic Research Expeditions, Interim Reports, No. 10, Jan. 1956.

unpaged. 6+ 11 figs. , 132 tables, No. 316-446, 6 refs. Also:

Firmstone, T. F. , Hourly measurements of ionospheric characteristics, Macauarie Island, 1954. Ibid. , No. 12, Dec. 1955.

unpaged. 8 figs. , almost entirely tables, 3 refs. Also: Callow, D. R. L. , Hourly measurements of ionospheric characteristics, Macauarie Island, 1955. Ibid. , No. 13, Aug. 1955.

unpaged. 11 figs. , almost entirely tables. DWB--Extremely

detailed tabular and graphical presentation of the hourly data

obtained at Macauarie Island (54°29'S, 158°58'E., Geomagnetic 61°S, 283 d

E). Hourly values of f°F2, f°Fl, f°E, fE,

H'F2, h'Fl, h'E, h'Es , hpF2, (M3000) F2 and M(3000)F1. Data

for Sept. 1953 are missing. Records began in June 1950. -- M.R.

A-770 Little, C. G. , High latitude ionospheric observations using

extraterrestrial radio waves . Institute of Radio Engineers,

Proceedings, 42:1700---, 1954. --A preliminary account is given

of observations made at College, Alaska, over a two-month

period in the spring of 1954, of the effect of the ionosphere on

the reception of cosmic radiation at 65 mc. Strong absorption

of the diffuse rf background is most common at midday and

least common during late evening; it is correlated with no-echo

conditions and with variations of the geomagnetic field. Observations on localized radio sources indicate that scintillations are commoner in Alaska than in England. Scintillations

were observed whenever marked 55-mc absorption occurred during transit of the localized source through the antenna beam;

this indicates that the lateral distribution of ionization during

periods of absorption is nonuniform. Study of the scintillations should provide information about irregularities in the

ionosphere.
226

A-771 Little, C. G. ; Rayton, W. M. and Roof, R. G. , Review of

ionospheric effects at VHF and UHF. Institute of Radio Engineers, N. Y. , Proceedings, 44(8): 992-1018, Aug. 1956. 2

tables, 182 refs. 3 + eqs. DLC--This paper summarizes the

present-day knowledge of ionospheric effects at VHF and UHF,

with the exception of forward scattering of VHF radio waves by

the ionosphere. The seven effects covered in the paper are: Radar echoes from aurora. Radar echoes from meteors, The

Faraday effect and Radar echoes from the moon, Radio noise

of auroral origin, Absorption of radio waves by the ionosphere,

Refraction of radio waves by the ionosphere, and the Scintillation of the radio stars. Each ionospheric effect has in turn

been divided into separate subtopics, and the main results are given in these subsections, with particular emphasis upon

providing references to the original papers. In this way the

reader wishing to know the answer to a specific problem will

speedily be able to find a summary of the main published re- sults in the field, and also be able to learn which papers deal

with the particular topic of interest. --Authors' abstract.

A-772 Little, C. G. and Leinbach, H. , The riometer — a device for

the continuous measurement of ionospheric absorption. Institute of Radio Engineers, N. Y. , Proceedings, 47(2):315-320,

Feb. 1959. 4 figs. , 6 refs. DLC--A sensitive, self-balancing, noise -measuring equipment, known as the riometer, is

described. This instrument has been designed for routine measurement of ionospheric absorption during the IGY, using the

cosmic noise method. Application of this technique in the

auroral zone has resulted in quantitative measurements of ionospheric absorption, even during polar blackouts. The riometer has the advantages over a simple total -power cosmic

noise receiving system of 1) linear response to changes of imput noise power, 2) high accuracy in the presence of narrowband RF interference, and 3) good long-term stability. --Authors' summary.

A-773 Lorentz, Hendrick Antoon, The theory of electrons and its

application to the phenomena of light and radiant heat. Leipzig, B. G. Teubner, 1909. 332 p. refs. , numerous eqs. DLC

--A large theoretical text which takes up in successive parts:

I. General theory of free electrons which stems from theories

of FARADAY and MAXWELL; p. 1-68; II. Emission and absorption of heat radiation after KIRCHOFF, BOLTZMANN,WIEN

and JEANS, p. 68-97; III. Theory of Zeeman effect, p. 98-131;

IV. Propagation of light in a body composed of molecules. Inverse Zeeman effect, p. 132-167; V. Optical effect in moving

bodies, p. 168-230. The newly accepted theory of relativity

of EINSTEIN is considered in the last chapter. All of the known

effects, phenomena and theory which enter into wave propagation
227

in the ionosphere are treated in this classical treatise on the

electron, originally presented in a series of lectures at Columbia University in 1906. --M. R.

A-774 Lovell, A. C. B. , A note on the interpretation of transient

e choes from the ionosphere. Journal of Atmospheric and Terrestrial Physics, London, 8(4/5): 293-294, May 1956. fig. , 6 refs. DWB--The midday maximum occurrence of transient

echoes from meteor trails is attributed to a maximum of meteoric activity at midday in summer, as shown by surveys. -- C.E.P.B.

A-775 Low, Ward C. and Knight, Raymond M. , Rocket reception of

radio pulses over long distances. Boston University. Upper

Atmosphere Research Laboratory, Contract AF 19(122) -36, Investigation of the ionosphere utilizing sounding rockets, Final

Report, June 30, 1953. 65 p. tables, numerous figs. MHBH--This is the final report on Contract AF 19(122) -36 between

the Department of Defense and the Trustees of Boston University. It also marks the conclusion of the project usually termed the 'Oblique Incidence Ionosphere Experiment, " here called

briefly the "Ionosphere Experiment. " The principal goal of this

project has been to obtain general information concerning characteristics of long distance radio pulse reception in high altitude rockets, more specifically, whether significant deviations

from results of simple propagation theory result from the receiving stations being in, or very near, the E-layer. To the limited

extent to which the recovered data have been examined, no

such anomalies have been recognized. A description of the

equipment employed on this experiment in three high altitude

missiles: V-2 No. 51, and AFCRC Aerobee Rounds No. 20

and No. 24 is presented. A display of data obtained during

the flights of those missiles is given, with a discussion of

the methods of measurement used. --Authors' abstract.

A-776 Low, Ward C. , An instrument for investigation of non-linear

effects of the ionosphere. Boston Univ. Upper Atmosphere

Research Laboratory, Contract AF 19(604) -757, Final Report,

Oct. 31, 1954. 25 p. figs. (incl. photos), refs. , eqs. DWB

--The design and construction of two CW rocket transmitters

are described. Specifications were supplied by Air Force Cambridge Research Center. The transmitters are to provide the

wanted wave in an ionospheric cross -modulation experiment.

A review and extension of applicable cross -modulation theory

is given, including suggestions for detailed analysis methods

of experimental data which may be obtained. It is suggested

that the specified wanted wave frequency may be higher than

desirable. The effective altitude ranges in which useful data

may be expected are found to be narrow. Additional study is
228

recommended before performance of the experiment as presently designed. --Author's abstract.

A-777 Luscombe, G. W. , Delayed signals in ionospheric forwardscatter communication. Nature, London, 180(4577): 138, July

20, 1957. fig. , 3 refs. DWB--VHF signals received in the

United Kingdom from Gibraltar with a delay of 140 m sec are attributed to round the world propagation. --C. E. P. B.

A-778 Lutz, S. G. ; Losee, F. A. and Ladd, A. W. , Pulse phasechange signaling in the presence of ionospheric multipath distortion. Institute of Radio Engineers, Transactions, CS-7(2):

102, June 1959.

A-779 Lyon, A. J. and Moorat, A. J. G. , Accurate height measurements using an ionospheric recorder. Journal of Atmospheric

and Terrestrial Physics, London, 8(6):309-317, June 1956. 8

figs. , 6 refs. , 3 eqs. DWB--The errors of the D. S. I. R.

(Slough) ionospheric height recorder are discussed. Checking

of the calibration procedure is described, and a method is

given for correcting errors in height measurement due to distortion of the echo-pulse in the receiver. With a calibrated

receiver and expanded time-base, E region equivalent heights

can be measured to + 2 km. Without such correction systematic errors of + 5 to 15 km are present in height and MUF measurements at ionospheric stations all over the world. --C. E. P. B.

A-780 Lyons, J. F. , Analyzing multipath delay in communications

studies. Electronics, 32(36):52-55, Sept. 4, 1959. 7 figs. , ref.

A-781 McCue, C. G. , Concerning Green's reinterpretation of the

magneto-ionic theory. Journal of Atmospheric and Terrestrial

Physics, 3(5):239-244, June 1953. fig. , 12 refs. , 19 eqs.

MH-BH--A. L. GREEN (1949-50) justified his empirical maximum usable frequency (M. U. F. ) formula by a new analysis of

the magneto-ionic theory of radio transmission. Author considers that this modification of E. V. APPLETON's interpretation (1932) is incorrect. --C. E. P. B.

A-782 McKenzie, A. A. , Reliable VHF signals up to 1. 250 miles

distance. Electronics, N. Y. , 25(6): 102-103, June 1952. 2

figs. , 4 refs. DLC--Signals which can regularly be heard at

great distances, with an optimum at noon and poorest reception between 20 and 22 h (E. S. T. ), are attributed to a phenomenon similar to the sporadic E layer (Es) but not sporadic.

The signal is enhanced during magnetic storms and SID's when

other high frequency signals fade out. It must come from the

part of the E layer below the level of maximum ionization or
229

even below the absorbing region of the D layer. (See Physical

Review, p. 141, April 1952. )--M. R.

A-783 McKerrow, C. A. (Defence Research Board, Ottawa), Some

recent measurements of atmospheric noises in Canada. Institute of Radio Engineers, h. Y. , Proceedings, 45(5): 782-786,

June 1957. 5 figs. , 2 tables, 6 foot-refs. DLC -Some recent

atmospheric noise measurements in the vlf range have been

made in Canada by the Defence Research Telecommunications

Establishment of the Defence Research Board. The amplitude

of the mean logarithmic power (mlp) of atmospheric noise on a frequency of 10 kilocycles has been measured -at Ottawa, Ontario (lat. 45. 4°i4, long. 75.9 W), over a period of one year,

beginning in Oct. 1955. The mlp atmospheric noise amplitude

has also been measured in the sub-Arctic regions of Canada

at Churchill, Manitoba (lat. 58. 8°K, long. 94. 2°W), on a frequency of 107 kc for the period Dec. 1955 to Aug. 1953.

A brief description of the equipment used to obtain these measurements is described. The results of the measurements are presented in the form of a graphical analysis showing the hourly median variations. These measurements are compared with

previous measurements made in Canada, and with the estimated values of the National Bureau of Standards, and CCIR predictions of July 1956. --Author's abstract.

A-784 Macmillan, R. S. ; Rusch, W. V. T. et al. , Very-low-frequency antenna for investigating the ionosphere with horizontally polarized radio waves. U. S. National Bureau of Standards,

Journal of Research, Sec. D, 64(l):27-35, Jan. /Feb. 1960. 13

figs., 12 refs. , 16 eqs. DWB, DLC--The advantages of a horizontal half-wave resonant antenna for very-low-frequency propagation experiments lie in its relatively simple and inexpensive construction and in its radiation pattern which is maximum

in the vertical direction. The radiation fields of this type of

antenna located at the surface of a conducting earth consist of:

1, a horizontally polarized space-wave radiated in the perpendicular bisector plane of the antenna; and 2, a vertically polarized ground-wave field radiated along the axis of the antenna.

This vertically polarized field is zero at right angles to the an- tenna. These fields have been experimentally verified. The

use of a 50-kilocycle horizontal half-wave antenna for vertical

incidence ionospheric sounding experiments is described. The

radiation pattern of this antenna is well suited for ionospheric

soundings since a receiver located in the ground-wave null re- ceives only the reflected skywave signal. Ground-resistivity

measurements made at a number of locations in Central and

Southern California were correlated with the geology of the

terrain. This correlation showed that the ground resistivity

is highest (a condition necessary for optimum antenna efficiency)
230

in areas where the underlying rock formations are relatively

unfractured. The amount of annual rainfall and other climatic

conditions have little or no effect on the resistivity. Finally,

a unique antenna system is presented which employs resonant

loading circuits to convert a section of an existing power line

into a horizontal half-wave very-low-frequency transmitting an- tenna. --Authors' abstract.

A-785 Macmillan, R. S. ; Rusch, W. V. T. and Golden, R. M. , A new antenna to eliminate ground wave interference in ionospheric sounding experiments. Journal of Atmospheric and Terrestrial Physics, 13(1/2): 183-186, Dec. 1958. 5 figs.

A-786 Mclsicol, R. W. E. and Gipps, G. de V. , Characteristics of

the Es region at Brisbane. Journal of Geophysical Research,

56(1):17-31, March 1951. 10 figs. , 10 refs. DWB--A study

based on routine h'f records of the Es layer taken at Brisbane,

Australia, between June 1943 and Dec. 1949 shows at all seasons the critical frequency is lowest at dawn. In summer it reaches a maximum at 10 hr and declines gradually. In winter

the rise is slower and the maximum occurs around 14 hr, dropping markedly by sunset. The observations suggest that there

are 2 distinct types of Es at Brisbane - one found at great heights and descending to its final position, the other formed in

situ. The first is predominant in summer and the second in

winter. No evidence of correlation could be found with sunspot numbers, ionospheric storms or meteor occurrence frequency, and the conclusion is reached that the Brisbane Es is

not predominantly of meteoric origin. There is some slight

evidence of correlation between the constant height type of Es

and F region diffuseness. --From authors' abstract.

A-787 McNicol, R. W. E. ; Webster, H. C. and Bowman, G. G. , A study of "Spread-F" ionospheric echoes at night at Brisbane,

Pt. 1, range spreading (experimental). Australian Journal of

Physics, Melbourne, 9(2):247-271, June 1956. 26 figs. , 5

photos, 3 tables, 11 refs. DLC. Also: McNicol, R. W. E.

and Webster, H. C. , Pt. 2, Interpretation of range spreading.

Ibid., p. 272-285. 8 figs., 15 refs. , eqs. DLC --Examination

of ionospheric records on 2. 28 Mc/s at Brisbane, Buderim

(95 km N) and Toowoombe (95 km W) shows satellite echoes

accompanying the nighttime F2 echo. The characteristics of

these multiplets (points of juncture, intensities, multiple hop

satellites, spatial correlation, duration of multiplets and individual satellites, diurnal and seasonal distribution, relation to F and Es, etc. ) are described and shown in graphs and

photos of records. Movements approximately 240 + 140 km/hr

with a direction of 290 + 60 , duration averages 50 min, oc- currence is more frequent in winter than in summer, etc.
231

Theories of origin are given in Part II. Motions are considered

to be wave motions rather than a drift of ionosphere. Only a few of the multiplets are thought to be due to Es scatter with

return path via F2.--M. R.

A-788 Maeda, K. ; Aono, Y. ; and Kobayashi, T. , A tentative method of calculation of h. f. radio sky wave field intensity by use

of transmission curve. Japan. Science Council. Ionosphere

Research Committee, Reports on Ionosphere Research in Japan,

4(2):61-70, 1950. --Gives the principle underlying the proposed

graphical method of calculation of h. f. radio field intensity.

A Ev /f curve (field intensity v. frequency at vertical incidence)

and an ordinary h'/f curve are needed. Smith's transmissioncurve method (1939) is applied and by a deduction of analytical relationships, between attenuations at oblique and vertical

incidences, it is shown that ambiguity or speculation in the

estimation of mean collision frequency and of its distribution

can be removed. Some examples and curves are given.

A-789 Maeda, Ken-ichi (El. Comm. Lab. , Ministry of Telecom. , J apan) , Dynamo-theoretical conductivity and current in the

ionosphere. Journal of Geomagnetism and Geoelectricity,

Kyoto, 4(2):63-82, July 1952. DLC--Tensor expressions of

anisotropic velocity and conductivity of a simple ionized gas

in magnetic field is applied to the ionosphere as a heterogeneous ionized medium. It is shown that the vertical electric

current in the ionosphere is suppressed down to a negligible

magnitude, and under this condition the specific conductivities of the ionosphere are derived. With these conductivities

the dynamo-theoretical equation is constructed and solved for

some special models of the ionospheres. The directional conductivities of the ionosphere are introduced and explained.

The vertical motion of electrons and ions in the ionosphere is

considered and its importance is briefly noted from the viewpoint of the ionospheric distribution. r-Author's abstract.

A-790 M«hlum, Bernt (Norwegian Def. Res. Establ. Kjeller, Lillestrom, Norway), Anisometry in the fading pattern of sporadic

E as observed near the auroral zone. AGARDograph, Paris,

No. 34:163-168, Sept. 1958. 3 figs. , 4 refs. DWB (629.

1323 1\ 864a) --The diffraction pattern formed over the ground

from the sporadic E-layer has been studied at Tromso (67 geom.

lat. ). The irregularities in the diffraction pattern are found to

be elongated in an east-west direction, and velocities of drift

up to 1600 m/s of the irregularities have been observed. --Author's abstract.
232

A-791 Maenhout, A. , Distribution en azimut des parasites atmospheriques recus a Dourbes sur ondes kilometriques. (Azimuth

distribution of sf erics received at Dourbes on kilometer waves.)

Ciel et Terre, Brussels, 73(ll/12):499-505, l\ov./Dec. 1957.

5 figs. DLC--The azimuth distribution of sferics received with

a Lugeon-Nobile type radiogoniograph tuned on the frequency

of 27 Kc/s is given for a typical winter month (Dec. 1956) and

for a typical summer month (June 1957). The measurements

were made at the Geophysical Center at Dourbes, Belgium. -- A.V.

A-792 Maire, J., hote sur les relations entre 1 'agitation du champ

magnetique terrestre et 1 'agitation ionospherique observee

dans les radiocommunications transcontinentales par ondes

decametriques. (Note on the relation between the disturbance

in the terrestrical magnetic field and ionospheric disturbance

observed in transcontinental radio communication by 10 m

waves.) Annates de Geophysique, 5(3):216-220/ July-Sept.

1949. 3 figs. , table, 6 refs. MH-BH--The author describes

a method of recording daily ionospheric disturbances over a

given distance as reflected in radio communication and discusses that variation of the amplitude of the ionospheric disturbances as a function of distance, the 27-28 day cycle of

ionospheric disturbances and the concomitant disturbances

of the earth's magnetic field. --I. L.D.

A-793 Maire, J. , Reception of transatlantic signals of frequencies

near 30 Mc/s. Annales de Radioel^ctricite, 6( ):197---,

1951. --Results of systematic reception tests made near Paris

from 1937 to 1940 and from 1948 onwards are shown diagrammatically and discussed. The transmissions are from WWV

and amateur stations. Regularity of reception throughout the

above two periods is related to the sunspot cycle, the time of

sunset at the mid-point of the path, and the predicted muf.

Reception of Buenos Aires transmissions on about 27. 5 mc

was, with minor exceptions, consistently good during much

of the daytime from 1946 to 1950, and was almost completely

free from echo disturbances.

A-794 Major, G. , D-layer ionospheric echoes at Macquarie Island.

Nature, London, 175(4463): 862 -863, May 14, 1S55. 2 refs.

DWB--Echoes at a minimum virtual height of 40 km were observed on most days of the year on 2-7. 5 Mc/s at Macquarie

Island. , occasionally persisting through the night. They may

be peculiar to islands. --C. E. P. B.
233

A-795 Major, G. , Hourly measurements of ionospheric characteristics, Macquarie Island, 1952. Australian National Antarctic

Research Expeditions, 1947-1949, Interim Reports, No. 9,

Jan. 1956. p. 220-315. Mostly tables. DLC (QC973. M25)

--Graphs and tabulation of hourly ionospheric characteristics

for Jan. , Feb., March, August, Sept., Oct., Nov. and Dec.

1952 in same form as for 1950, for Macquarie Island. --M. R.

A-796 Malinovski, Al. , Radiolokatsionna uredba za opredeliana

posoka i skorost na visokiia viatur. (Radar set for determining the direction and speed of upper air winds. ) Khidrologiia

i Meteorologiia, Sofia, ho. 4:46-53, 1953. 9 figs. Russian

and English summaries p. 53. DLC --The radar set described

in this paper is located at the Aerological Dept. of the Bulgarian Weather Service. It is designed to replace the conventional pibal theodolite in conditions of low visibility. The

radar triode transmitter operates in the 50 cm band. Great

accuracy of elevation and azimuth (1/10 deg) is achieved

through conical scanning. Range is measured directly on the

Type A indicator with a circular base with an accuracy of +

100 m. More accurate reading (+ 20 m) is possible when us- ing a special device "stretching" the base. The set has a peak power of 20 kw, pulse duration 2 sec, antenna beam

width of 5 . --Author's abstract.

A- 797 Mallinckrodt, A. J. , The boundary problem in ionospheric

wave propagation. Stanford University, Electronics Research

Laboratories, Contract AF 19(304) -795, Technical Report No.

2, May 1954.

A-798 Mallinckrodt, A. J. ; Snyder, W. and Helliwell, R. A. , Characteristic waves. Institute of Radio Engineers, Transactions,

PGAP-3: 53-62, Aug. 1952.

A-799 Manning, Laurence A. (Comp. ), A survey of the literature

of the ionosphere. Stanford University. Dept. of Engineering,

Final Report No. 1-FI (on high altitude radio frequency propagation) Aug. 30, 1947. (Contract W 33-038 ac -14737. 278

leaves, numerous figs. , tables and eqs. DWB--This valuable

bibliography contains the major part of the important papers on

radio propagation in the upper atmosphere and on ionospheric

physics. Aspects likely to be of significance to the problems

of missile communication on VHF are included. The 888 entries are abstracted and arranged alphabetically under the authors, and will also be found in the classified subject index and

through a provided code system. The last 76 leaves consist

of a digest section comprising the more important knowledge

on certain branches of the ionosphere. --W. N.
234

A-800 Manning, Laurence A. , Windmessunqen in der oberen Atmosphare. (Wind measurements in the upper atmosphere. ) Urnschau, Frankfurt a. M. , 51(8):245-243, April 1951. 2 figs.

DLC--Popular report on measurement of wind velocity at heights

of 50 to 70 miles, by radar echoes from ionization trails persisting after the passage of meteors, as carried out at Stanford

University, California. An explanatory schematic drawing and

data on wind velocity recorded during the summer 1949 are presented. --G. T.

A-801 Manning, Laurence A. (Stanford Univ. , Calif. ), Recent ad - vances in the study of ionospheric winds. American Meteorological Society, Bulletin, 34(9) :401 -405, Nov. 1953. 6 figs. , 4 refs. MH-BH--Two radio methods of ionospheric wind observation and the meteoric method are described in detail and il- lustrated. --M. R.

A-S02 Manning, L. A. , Ionospheric layer heights. IRE-URSI Meeting, Washington, D. C. , May 1955. --One of the simplest

methods for finding true height is that of Booker and Seaton.

By assuming the layer of parabolic form, they showed that the

true height of the layer maximum is equal to the virtual height

at 83. 4 percent of the critical frequency. An extension of

their analysis is given to include the effect of the earth's magnetic field. For geomagnetic latitudes north of 45 , the longitudinal approximation of the magneto-ionic equations applies

with very slight error. It then is possible to get analytic ex- pressions for the virtual height of reflection from a parabolic

layer. It is found that at these latitudes use of the BookerSeaton analysis yields less error if applied to the extraordinary rather than the ordinary trace. Curves are produced showing the error in neglecting the magnetic field, and also the

scaling frequency that gives the true height without error. The

method may be of especial usefulness in the International Geophysical Year.

A-803 Manning, Laurence A. , Survey of the literature of the ionos - phere. Stanford Univ. Radio Propagation Laboratory, Contract

AF 19(604) -683, Final Report, July 31, 1955. 650 p. illus.

,

tables, eqs. About 1400 abstracts arranged alphabetically by

author. ASTIA photostat. No. AD-75 477. "In essence a second edition of the Survey of 1947 which was prepared for the

Air Materiel Command". -The 1000 abstracts in the 1947 edition

have been increased to over 1400, and the annotated bibliography (p. 19-463) is supplemented by lists of journals, subjects

and institutions and their code abbreviations, a subject index

(p. 464-511), and a summary of knowledge of various aspects

of ionospheric physics and propagation (p. 512-650). The subjects discussed are: structure, recombination, disturbances,
235

propagation, methods of investigation, wave paths, height

analysis and meteors. The latest abstracts included are 1954,

the earliest about 1928. --M. R.

A-804 Manning, L. A. (Stanford Univ. , Calif. ), Report on URSI

Commission III, Ionospheric Radio Propagation. Institute of

Radio Engineers, Proceedings, 46(7): 1362-1366, July 1958.

Also issued as National Research Council, Wash., D. C.

Publication No. 581:51-101, 1958. DWB, DLC-The technical

program was divided into 8 parts: 1) lower ionosphere, 2) geomagnetic influences on ionosphere, 3) whistlers, 4) geomagnetic storms, 5) horizontal movements in ionosphere, 6) scattering in ionosphere, 7) solar flare of Feb. 23, 1956, 8) rocket

exploration of ionosphere. A fairly complete summary is given

of progress reported at the meeting on each of these subjects.

--M.R.

A-805 Marasigan, V. (Manila Obs. , Philippines), Height-gradient

of electron-loss in the F-region. Journal of Atmospheric and

Terrestrial Physics, London, 13(1/2): 107-112, Dec. 1958. 4

figs. , 14 refs. , 6 eqs. DLC--A theoretical expression is derived for the exponential height-gradient of the coefficient of

electron-loss in the F region, on the assumption that this gradient completely accounts for the initial process of bifurcation,

Five models are proposed: parabolic, linear, second-power,

cosine and quasi-parabolic. --Author's abstract.

A-806 Marasigan, V. (Manila Obs. , Philippines), Bifurcations in

the F-region at Baguio. 1952-1957. Journal of Atmospheric

and Terrestrial Physics, London, 13(1/2) :2S-31, Dec. 1SS8.

5 figs. , 13 refs. , eqs. DLC--A 5-year statistical survey of

bifurcations in the F region at Baguio is presented and analyzed in the light of a parametric mechanism of the v-R relations

of the Fl and F2 layers. The conclusion is reached that two

of the features of bifurcation statistics are mainly due to variations in layer heights and thicknesses with season and solar

activity respectively. --Author's abstract.

A-807 Marcou, R. J. (Boston College, Newton, Mass. ); Pfister, W.

(A.F.Cambridge Res. Center, Bedford, Mass.) and Ulwick,

J. C. (A. F. Cambridge Res. Center, Bedford, Mass.), Raytracing technigues in a horizontally stratified ionosphere using

vector representations. Journal of Geophysical Research,

Wash., D. C, 63(2) :301 -313, June 1958. 2 figs. , 9 refs. , 54 eqs. DLC--Vector expressions are derived for tracing oblique ray paths, taking into account the full effect of the

earth's magnetic field. The method is an extended analytical

treatment of POEVERLEIN's two dimensional case based upon

crystal optics. In particular, the unit vector 8 in the direction
236

of the ray and the vector expressions for the equivalent path

of the wave packet and the group refractive index are derived.

A method for high speed computers is described for ray tracing

in a horizontally stratified ionosphere, for determining, by an

iteration process, the index of refraction and wave normal direction, and for determining electron-density distributions from

rocket data. --Authors' abstract.

A-808 Mariani, F. , Densita elettroica in una ionosfera non isoterma . (Electronic density in a non-isothermal ionosphere.) Annali

di Geofisica, Rome, 9(l):43-62, Jan. 1956. 10 figs. , 4 refs.

,

33 eqs. English summary p. 61, DLC--This paper theoretically deals with the effects of the terrestrial curvature on the

ionization intensity and on the electron density in a non-isothermal atmosphere, for the two cases in which (1) the temperature gradient has a constant value at every height or (2)

assumes the value above a given height. A general relation

is found between temperature, electron density, generalized

recombination coefficient, matter density and absorption coefficient of the ionizing radiation, valid, in stationary conditions, for a monochromatic radiation. --From author's abstract.

A-809 Mariani, F. , Variazioni staqionali e non staqionali della densita elettronica ionosferica. (Seasonal and non-seasonal var- iations of the ionospheric electronic density. ) Annali di Geofisica, Rome, 10(1/2): 165-181, 1957. 10 figs. , 3 tables, 13

refs., 7 eqs. Italian and English summaries, p. 180-181. DLC

--A comparative study of the component N12 °f twelve months

period, present in the series of the median monthly values of

the maximum electron densities in the F2-layer, for about 20

observatories located between the geographical latitude 52 N

and 43 S, during the years 1949-1954, shows that its behaviour at noon exhibits a substantial phase-agreement between

the geomagnetic latitudes 53 N and 35 S; at midnight, instead,

the component N^2 exhibits a phase shift of 180 at the two

sides of the equator. With regard to the F 1 and E layers one

sees that they exhibit only seasonal characteristics. At first

sight, the behaviour of N12 in the F2 layer could be attributed

to a non-seasonal component having a twelve months period

but the same phase in the two hemispheres superposed to the

normal seasonal component; however the detailed analysis of

the noon and midnight behaviours of N^2 *n *ne F2 layer leads

to the conclusion that the eventual non-seasonal component

cannot be attributed neither to a radiation source external to

the solar system nor to the annual variations of the Sun-Earth

distance, greater during summer and smaller during winter. At

this stage of our knowledges, one could accept the view of a connection of the features of N12 *n * ne * wo hemispheres with

the phenomena of general circulation in the high atmosphere.

--Author's abstract.
237

A-810 Mariani, F. , Densita elettronica nell'alta atmosfera e interpretazione delle curve h' (f) dell'altezza virtuale della ionosfera. Parte 1. (Electron density in the upper atmosphere and

the interpretation of the curve h' (f) of the virtual height of the

ionosphere.) Annali di Geofisica, 6(l):21-45, Jan. 1953. Pt.

2, Ibid., 6(4):533-553, Oct. 1953. 18 figs. , 5 tables, 23

refs. , numerous eqs. English summaries p. 44-45, 553. DWB

--1) The group refractive index applicable to the vertical propagation of an electromagnetic wave in the ionosphere is calculated for the latitude of Rome by means of Appleton's formula.

The optical path of a wave of given frequency penetrating a parabolic layer is calculated for three different heights of maximum electron density and for various values of critical frequency. The geometrical parameter of electron distribution in

the ionospheric layers is determined by a theoretical revision

of an experimental curve of virtual height, thus obtaining the

thickness of every layer and its height above ground, considering both the cases of totally separated and of partially superimposed layers. 2) The optical path is calculated for an

electromagnetic wave which penetrates and is reflected by a

Chapman layer having a "semithickness" 2. 5 H (H = scale

height). Results are compared with those obtained in Pt. I for those ionograms in which the Fl and the "true" F2 layers

are partially superposed. The electron density distribution in

the superposition region is studied considering the recombination of the electrons and the ions and it is ascertained that the

model of linear superposition used in Pt. I must be replaced

by a more complicated model in which the electronic density

is N = FN2 + N

2 1 ** (Ni and N_ are the densities of the Fl -

I l 2 J

i 2

and the "true" F2 layers if they are independent). A preliminary comparison of the theoretical and experimental results

seems to give a better interpretation of the ionograms. --Author's abstract.

A-811 Mariani, F. (Inst, di Fisica dell'Universite, Roma), A new

theoretical model of the composite F-layer. Journal of Atmospheric and Terrestrial Physics, fc. Y. , 16(1/2): 160-173, Oct.

1959. 8 figs., 2 tables, 23 refs. , 8 eqs. DWB, DLC -A model of a composite F layer is developed to explain both the re- gular behaviour of the Fl layer and the anomalies of the F2

layer. The bifurcation in the Fl and F2 layers arises as an

effect of a discontinuity in the physical conditions of the upper atmosphere, namely a fairly rapid variation of the temperature vertical gradient. The assumed height variation of the

generalized recombination coefficient is cC- cCQ

-$ ^ N" T"' • Tidal movements have a smaller importance, because they

cause only secondary perturbative effects. --Author's abstract.
238

A-812 Mariani, F. (1st. Naz. Geofisica, Rome & 1st. Fisica Univ.

Rome), The worldwide distribution of the F2 layer electron

density: seasonal and non-seasonal variations and correlations with solar activity. Nuovo Cimento, Bologna, Ser. 10,

12(3):218-250, May 1, 1959. 8 figs. , 4 tables, 19 refs. , 9

eqs. English summary p. 218; Italian summary p. 240. DLC

--The worldwide behaviour of the twelve-month period (seasonal and nonseasonal) variation of the maximum electron density

N in the F2 layer appears noticeably different at noon and at

midnight. In each case, it is controlled by the geomagnetic

field and by the solar activity but, while it shows large asymmetric features at noon in the two hemispheres, it is fairly

symmetrical at midnight. It is not possible to account for the

experimental results by assuming some external source of radiation producing nonseasonal effects. One is led to assume

some terrestrial cause of asymmetry: for example, some effect

of general circulation in the upper atmosphere. With respect

to the correlation of electron density with solar activity, there

appears again some noticeable asymmetry in the two hemispheres; in particular, the northern hemisphere appears more

influenced by the solar hydrogen filaments, especially for increasing latitude. The explanation of these asymmetries, in

terms of some direct influence of the sun, is also puzzling,

so that, in this case, one is led to think of some more or less

unknown effect of solar corpuscular (or electromagnetic) radiation on the upper atmosphere, for example on its movements

or its conductivity. At the present stage of our knowledge, we

cannot exc.lude the possibility of a similar cause for both the

asymmetries of the twelve -month period variation and of the

correlations with solar activity. Further observational evidence is required. --Author's abstract.

A-813 Martyn, D. F. (Commonwealth Sc. and Ind. Res. Org. , Canberra, Australia), Travelling disturbances in the ionosphere. U. S. Air Force. Cambridge Research Center, Geophysical

Research Papers, No. 11:195-198, 1952. 8 refs. DWB--Brief

note on the problems of the apparently unrelated phenomena in

the F2 region are discussed such as: 1) The anomalies in intensities of multiple reflections, 2) the apparently vertically

travelling clouds of ionization, 3) the small disturbances of

virtual height and critical frequency, and 4) the systematic

errors in direction finding. These may all be due to 100-200 km

long waves of speed about 10^* cm/sec that travel horizontally.

--W. N.

A-814 Martyn, D. F. (Radio Res. Lab., C.S.I. R.O., Camden, N.

S. W. ). Processes controlling ionization distribution in the F2

region of the ionosphere . Australian Journal of Physics, Melbourne, 9(1):161-165, March 1956. 5 refs. , 5 eqs. DLC--
239

All indications point to the reliability of established atmospheric densities (lO^O particles per cc) at 300 km level, rather

than to the values (about 30 times less) obtained by recent

rocket soundings. If the latter were correct, the F2 region

would lower shortly after sunset to well below 300 km, which

is not the case. Hence there must be a systematic error in

density measurements by rockets at great heights. The re- sults of a thorough investigation into the effects of diffusion

processes in F2 layer is presented under the headings of: 1)

speed of diffusion of ionization under gravity and partial pressure gradient, 2) formation of stable Chapman regions by diffusion, and 3) formation of stable Chapman region by combined

action of diffusion and attachment gradient, and 4) interpretation of equatorial anomalies and parabolic shape of F2 region.

--M. R.

A-815 Martyn, D. F. , The normal F region of the ionosphere. Institute of Radio Engineers, N. Y. , Proceedings, 47(2): 147-155,

Feb. 1959. 6 figs. , 37 refs. , 13 eqs. DLC -The global morphologies of the Fl and F2 regions at magnetically quiet times

are reviewed, and attention also is given to the sunspot-cycle

variations. The physical conditions, temperature, pressure,

recombination coefficients, and collision frequencies are reas- sessed in the light of recent studies of rocket and satellite re- sults and of diffusion. The theory of the F region is reviewed

with special attention to Bradbury's hypothesis and to the effects of transport of ionization. Also considered are the morphology of ."spread-F" and radio star scintillation phenomena.

A theory of the latter is outlined, and it is shown that the un- dersurface of the F region is unstable at times of upward drift,

which appear to be the times when such phenomena are prominent. --Author's summary.

A-816 Martyn, D. F. (C.S. I. R.O. , Camden New South Wales, Australia), Large-scale movements of ionization in the ionosphere . Journal of Geophysical Research, Wash., D. C. , 64(12):2178-

2179, Dec. 1959. ref. DLC --The complexity of the causes of

variations in the motions of ionization in the ionosphere is

noted, as is the difficulty of differentiating real and virtual

motions. An instability mechanism for deviations in ionization density is suggested, for which the predicted temporal

and spatial morphologies appear to be consistent with those

of the occurrence of sporadic E, spread F, and radio-star scintillations. --Author's abstract.

A-817 Mason, Ruth F. (Geophysical Obs. , Christchurch, New Zealand), Some observations on night-time ionospheric storms at

Christchurch. New Zealand Journal of Geology Geophysics,

Wellington, l(3):519-529, Aug. 1958. 6 figs. , 6 tables, 4

refs. Abstracted from reprint. DWB (M:538. 7 M411so)--
240

Data from ionograms are discussed in relation to the description of night-time storms at Christchurch. A consideration of

seasonal variation shows that in winter, storms have features

not noticeable in other seasons. Electron distributions are calculated for the early hours of both severe and moderate

storms; all show an initial increase in the number of electrons

up to maximum density level prior to the storm decrease normal for this latitude. --Author's abstract.

A-818 Massey, N. S. W. (Univ. Coll. , London), The formation of

the ionosphere. International Council of Scientific Unions.

Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 9-31. 33 refs. , eqs. DWB--Prevailing theories are reviewed and a model ionosphere comprising

all of the characteristics (Physical and chemical) presented.

Points which must be cleared up by future research are elaborated on. Discussion by APPLETON, VEGARD, MASSEY,

BERKNER, MAEDA and others are given in extenso. --M. R.

A-819 Matsushita, Sadami (High Alt. Observ. Univ. Colorado), On

the artificial geomagnetic and ionospheric storms associated

with high-altitude explosions. Journal of Geophysical Research, Wash., D. C, 64(9):1149-1161, Sept. 1959. 10 figs.,

table, 14 refs. DLC- -Geophysical effects of nuclear explosions at Johnston Island on Aug. 1 and 12, 1958, were studied

by means of IGY geomagnetic and ionospheric data collected

at various stations in the Pacific area and the American continent. The explosion heights are estimated at 70 to 80 km

and about 40 km, respectively. Immediately after each explosion, three phenomena occurred. (1) Strong counterclockwise

circular electric currents were formed in the vicinity of Johnston Island at 80- to 100-km height. They caused the immediate occurrence of artificial magnetic storms in the central

Pacific. (2) High-energy particles moving along the magnetic

lines of force caused auroras seen from Apia, and also caused

the main parts of the magnetic storms observed at Apia. (3)

X-rays due to the explosion caused the increase of the D-region absorption observed at Maui. Irregularities of the electron density in the F layer at Maui and the maximum geomagnetic change at Honolulu were caused by a shock wave from the

explosion. The degree of ionization in a wide area in the central Pacific increased to about 10 times normal within 35 min

after the first explosion and within about 6 hrs after the second.

Then a strong radio absorption continued for many hours.
241

A-820 Maurain, Charles Honore, L 'etude physique de la terre; interieur, couche superficielle, atmosphere. (Physical study

of the earth; interior, surface layer and atmosphere. ) Paris,

Presses Universitaires de France, 1949. 127 p. DWB--Most

of this pocket size book is concerned with the study of the interior of the earth and application of geophysical methods of

prospecting or of investigating the structure of the earth's

crust. Chap. IV consists of a non-technical discussion of

the methods of exploring the atmosphere, including manned

and sounding balloons (for temperature and pressure), pilot

balloons (for wind) and indirect methods such as by studying

meteor trails, clouds, the aurora, light of the night sky, twilight phenomena, solar radiation, absorption by ozone and

water vapor, explosive waves and radio waves or sferics.

Lastly, the ionosphere and solar relations (variations in the

solar constant and weather) are discussed. --M. R.

A-821 Maxwell, A. , Turbulence in the upper ionosphere. Philosophical Magazine, 45(371): 1247-1234, Dec. 1954. --From the

experimental data at present available it is shown that the

Reynolds number in the upper F-region (300-400 km level) is

of the order of 300. The region may therefore be turbulent.

It is suggested that the high level diffracting screens which

give rise to spread F-echoes and to radio star fading are caused by non-laminar flow, and that their non-appearance

during the daylight hours may be due to the inhibition of turbulence by large temperature gradients, by lower drift velocities or by an increase in the kinematic viscosity.

A-822 Meadows, R. W. , The attenuation of radio waves reflected

from the E-reqion of the ionosphere. Institution of Electrical

Engineers, Pt. B, 105(1 ):22, Jan. 1S58.

A-823 Meek, J. H. (Radio Physics Lab. , Ottawa), Prediction tech- niques at high latitudes. (In: Polar Atmosphere Symposium,

Oslo, July 2-8, 1958, Proceedings, Pt. 2, Ionospheric Section.

N. Y. Pergamon Press, 1958. p. 101-107. 8 figs. ) Also

issued in Journal of Atmospheric and Terrestrial Physics, London, Special Supplement, Pt. 2, 1957, pub. 1958. p. 101-107.

DWB, DLC--The method of HF predictions developed in Canada

is designed for application to high latitude and polar communication circuits. Objections to the present system of group predictions are raised. The Canadian system is based on the lin- ear relationship between the critical frequency and the sunspot

number, F = A + BS where F is the critical frequency; S the

sunspot number and A and B, constants. The relation between

the critical frequency and the sunspot number and the variations between zero intercept and the time of day at one particular station for different seasons of the year, are shown in the
242

illustrative figures. An example of an oblique incidence re- cord is given from which the separation between ordinary and

extraordinary traces is visible. Five results of some previous

experiments are cited. This method of predictions has reduced

the work involved in making the prediction charts.

A-824 Mende, H. ; Rawer, K. and Vassy, E. , Absorption radioelec - trigue par la basse ionosphere, mesuree a bord d'une fusee.

(Radioelectric absorption in the lower ionosphere, measured

from a rocket.) Annales de Geophysique, Paris, 13(3):231-

233, 1957. table. DLC.

A-825 Menzel, W. , Das "Wetter" in der Ionosphare. (The weather

in the ionosphere. ) Meteorologische Rundschau, 3(7-8): 176-

177, July-Aug. 1950. DWB--Briefly discusses ionization at

different levels, daily and seasonal changes, measurement by

wireless waves, effect of sunspots. --C.E. P.B.

A-826 Merrill, R. G. , Radiation patterns in the lower ionosphere

and Fresnel zones for elevated antennas over spherical earth. U. S. National Bureau of Standards, NBS Report, 5599, Sept.

10, 1958. 68 p. 20 figs., 9 tables, 21 refs. , eqs. DWB

(621.384 U585rad) --Patterns of elevated antennas produced by

reflection from spherical earth have been computed incorporating parallax, refraction, tropospheric defocusing, spherical

divergence, and near-horizon diffraction. Antenna siting data

are given for standard refracting at VHF for a scattering height

of 85 km: 1. Antenna height and elevation angle for placing

the maximum of the first lobe at the path midpoint; 2. Distance

from the antenna which define the first Fresnel zone. 3. Data

Data for determining obstacle effects and the elevation of the

zero phase surface in the Fresnel zone: this concept is introduced as a new basis for obstacle criteria. These patterns

and those for a temperate over-water refraction, and siting

data for the latter case, will be published as appendices. A

preliminary computation of optimum antenna height is given

which indicates that a considerable range of heights lower

than those given in (1) will have a greater or equal gain. -- Author's abstract.

A-827 Merrill, R. G. , Optimum antenna height for ionospheric scatter propagation. U. S. National Bur. of Standards, NBS Report, 6047, March 18, 1959. 13 p. 8 figs. , 10 refs. , 2 eqs.

DWB—Radiation patterns of elevated antennas over spherical

earth for scatter propagation in the lower ionosphere incorporation refraction, parallax, spherical divergence, and tropospheric defocusing have been used to compute the height gain

function resulting from raising and lowering symmetric transmitting and receiving antennas for a fixed path length. This
243

height gain function shows that a broad range of lower antenna

height has a gain over that antenna height computed with the

same model which places the maximum of the first lobe at the

path mid-point. The maximum of this function is defined as

the optimum antenna height. --Author's abstract.

A-828 Merritt, Ernest and Bostwick, William E. , A visual method

of observing the influence of atmospheric conditions on radio

reception. National Academy of Sciences, Wash. , D. C.

,

Proceedings, 14(11): 884-888, Nov. 1928. DLC-The experiment described is that of a partial separation of the ground

waves and the sky wave in radio communication. Two balanced coils were used (A and B). The A coil mounted with its

plane vertical and directed toward the sending station, the B

coil in vertical plane at right angles to this direction. The

latter coil responds only to that component of the sky wave

which is polarized with its electric vector horizontal and is

not affected by the ground wave. Suitable amplification to

one pair of plates of a cathode ray oscilloscope featuring res- pectively horizontal and vertical movements, combination of

which results in a Lissajous figure on the screen. An example

of the method as used during the presence of aurora is described. Further studies especially during sunset are contemplated.

--W. N.

A-829 Mihran, T. G. , A note on a new ionospheric -meteorological

correlation. Institute of Radio Engineers, Proceedings, 36(9):

1093-1095, Sept. 1948. fig. , 16 refs. DLC--A correlation between time-of -occurrence of maximum F2 critical frequency and

average pressure was found on some days in Nov. , Dec. 1945

and in Feb. - March 1946. --W. N.

A* 830 Mikhnevich, V. V. , Nekotorye rezul'taty issledovanii verkhnei atmosfery. (Some results of investigations of the upper

atmosphere.) Priroda, No. 5:71-72, 1958. DWB, DLC-The

data obtained by a rocket flight, up to a height of 473 km and

with a payload of 1520 kg, which took place on Feb. 21, 1958

in the U. S. S. R. is summarized. Measurements of electron

concentration in the upper ionosphere showed that there is no

sharply marked ionospheric layer at 110-120 km. The electron

concentration above 110-120 km diminished slightly and increased gradually up to 250-300 km. Above this level at about

300 km the concentration of electrons diminishes slowly so

that at 470 km the electron concentration is equal to one million of electrons per cubic centimeter. The existence of a large concentration of electrons at 400-500 km, where the concentration of neutral particles is greater than that of electrons,

may be explained by the intense diffusion electrons from lower

lying regions of the ionosphere. Also it was established that
244

at 100 km there is separation due to diffusion. Collisions between particles at heights up to 300 km were recorded. The

greatest height up to which pressure was measured - 260 km - was attained during rocket investigation in the U. S. S. R.

A-831 Millington, G. , Propagation at great heights in the atmosph- ere. Marconi Review, 21(131): 143-160, 1958. 9 figs. , table,

10 refs.

A-832 Millington, G. , Ray-path characteristics in the ionosphere.

Institution of Electrical Engineers, Proceedings, Pt. IV, 101

(7):235-249, Aug. 1954. 14 figs. , table, 12 refs. , 73 eqs.

DLC--The paper is based on an earlier one by the author and

presents an improved method of making magneto-ionic calculations that is both quicker and more accurate than the graphical construction previously given. By means of a new parameter the symmetrical cases can be studied in a simple manner and the asymmetry in the general case can be more readily

examined. Propagation in the magnetic meridian plane is discussed in detail, including the phenomenon described by

POEVERLEIN of a cusp at the apex to the ray path within a certain critical angle of incidence. The problem of directionfinding errors at short distances due to the lateral deviation

caused by the earth's magnetic field is treated as a perturbation of the vertical incidence case, and it is shown that the

effect is likely to be large only under critical conditions that

it would be difficult to obtain in practice. The paper ends

with a short discussion of absorption, with special reference

to the effect of the earth's magnetic field on non-deviative absorption. --Author's abstract.

A-833 Millman, George H. (Pa. S. Coll. Ionosphere Res. Lab. ), Initial ionosphere wind measurements at 150 Kc/s. Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic Ionospheric Research, Technical

Report, No. 17, Dec. 25, 1950. 30 p. + 35 figs., 21 refs.

,

eqs. DWB--Four experimental tests were carried out during

the first part of 1950 to measure winds in the E layer at 150

kc/s at vertical incidence. Direction and magnitude of winds

observed April 3 between 2000 to 2400 LMST and June 29 between 1900 to 2330 LMST are calculated and tabulated. Double and triple spaced receivers were used. The amplitude of

the first hop echo as a function of time was recorded four times.

Fading records obtained (1) during an ionospheric storm, (2)

during less disturbed period of an ionospheric storm and (3)

under normal conditions are statistically analyzed for a Rayleigh and a Gaussian distribution of the amplitude of the re- flected signal and change in amplitude respectively. --W. N.
245

A-834 Millman, George H. (Ionosphere Res. Lab., Pennsylvania

State Col. ), A note on ionospheric wind measurements at 150

Kc/s . Annales de Geophysique, Paris, 7(4):272-274, 1951.

3 figs. , 6 refs. MH-BH--The method used in ionospheric wind

measurements, currently conducted at the Ionosphere Research

Laboratory, Pennsylvania State College, is briefly described.

The magnitude and direction of wind is calculated from the amplitude of hop-echoes reflected from the lower edge of the E layer, as recorded by 3 receivers placed at the corners of a right

triangle. The high-power impulse transmitter operates at about 5 km from the receivers at a frequency of 150 Kc/sec.

Data on ionospheric wind directions and magnitudes for July

and Aug. 1951 are presented and commented on. --G. T.

A-835 Millman, George H. , A study of ionospheric winds and turbu - lence utilizing long radio waves . Pennsylvania State College.

Ionosphere Research Lab. , Contract AF 19(122) -44, Scientific

Report No. 37, May 30, 1952. 124 p. 55 figs. , 3 tables,

eqs. Also issued in Annales de Geophysique, 8(4):365-384,

Oct. /Dec. 1952. DWB--Author discusses briefly the dynamo

theory, the tidal oscillation theory, a model of the upper circulation and the theory of wind measurements — including general equations derived for calculating ionospheric wind speeds

and directions (utilizing three spaced-receivers). A method

for determining the height of these winds is presented and evidence indicating diurnal and seasonal variations of the movement of upper atmospheric winds is given. Data from July

1951 through March 1952 are statistically analyzed and compared with theoretical postulates. A survey of the problem of

fading is included. The 150 Kc/s equipment used is described

in detail. Suggestions are made as to further data analysis to

study the existence of lunar and solar tidal effects on ionospheric wind movements. Simultaneous short and long wave

measurements of winds should be made.-- W. N.

A-836 Millman, George H. , Analysis of tropospheric. ionospheric

and extraterrestrial effects on V. H. F. and U. H. F. propagation.

General Electric Co. Electronics Div. , Technical Information

Series, R56EMH31, Oct. 6, 1956. 138 p. 68 figs. , tables,

50 refs. , numerous eqs. Photostat copy. DWB (M94. 7

M655an) --Effects of the atmosphere and extraterrestrial noise

sources on the propagation of VHF and UHF radio waves are discussed. Relationships are derived for calculating refraction effects, time delays, Doppler errors, polarization changes and attenuation of radio waves traversing the atmosphere.

These conclusions were reached. Refraction and time delay

effects in the troposphere are independent of frequency and

are a direct function of relative humidity in the air. In the
246

ionosphere refraction and time delay errors, polarization shift

and attenuation are inversely proportional to the square of frequency. The Doppler frequency error in the troposphere is directly proportional to frequency while in the ionosphere is inversely proportional to frequency. The theoretical total radiation from the quiet sun, in the radio frequency spectrum, is

directly proportional to frequency raised to about the 0. 755

power. The total flux density emanating from radio stars,

Cassiopea and Cygnus, is inversely proportional to the frequency raised to the 0. 81 power. --S. P.

A-837 Millman, George H. (General Electric Co, Syracuse, N. Y. ),

Atmospheric effects on VHF and UHF propagation. Institute

of Radio Engineers, Proceedings, 46(8): 1492-1501, Aug. 1958.

16 figs. , 4 refs. , 53 eqs. DLC, DWB--This report discusses

the effects of the troposphere and ionosphere on the propagation of VHF and UHF radio waves. In order to accurately calculate the refraction effects, time delays, Doppler errors,

polarization changes and the attenuation experienced by radio

waves traversing the entire atmosphere, the author has derived

some mathematical relationships. Tropospheric refractive index profiles and ionospheric electron density models representative of average atmospheric conditions are also presented in

this paper. --N. N.

A-838 Millman, George H. (G. E. , Syracuse, N. Y. ), The geometry

of the earth's magnetic field at ionospheric heights. Journal

of Geophysical Research, Wash., D. C. , 64(7): 717-726, July

1959. 5 figs. , 7 refs. , 20 eqs. DLC--

A-839 Mimno, Harry Rowe, The physics of the ionosphere. Reviews

of Modern Physics, 9(l):l-43, Jan. 1937. 16 figs. , 309 refs.

,

24 eqs. DLC --This important paper opens with a brief historical survey followed by a simple analysis of the more prominent

features that distinguish the components of the radio spectrum.

A more detailed discussion includes following topics among

others: thunderstorms and barometric effects, local ionospheric

clouds, scattering and interaction of radio waves, etc. It is

concluded that the complex physical system requires study by

statistical methods. The classical magneto-donic theory, or rather the anomalies, is considered. The molecular atomic

ionization and recombination processes await a generally ac- cepted theory explaining the stratification of the ionosphere.

--W.N.
247

A-840 Minnis, C. M. and Bazzard# G. H. (both, D. S. I. R. Radio

Res. Station, Slough), Some indices of solar activity based

on ionospheric and radio noise measurements. Journal of Atmospheric and Terrestrial Physics, New York, 14(3/4) :213-

228, June 1959. 5 figs. , 4 tables (in appendix), 10 refs. , 17 eqs. , 4 eqs. (in appendix). DWB, DLC.

A-841 Minozuma, F. and Enomoto, H. , The mechanism and distribu- tion of short period fading under conditions of ionospheric turbulence. Physical Society of London, Proceedings, Ser. B,

67(3):211-216, March 1, 1954. 6 figs. , 7 refs. , 12 eqs. DWB

--Relations between distribution and rate of change of field intensity, and the turbulence which produces them are discussed

and compared with transmissions from JJY Tokyo (4 and 8 Mc/s),

The turbulence model in the ionosphere gives a turbulent diffusion coefficient A ^ (Z) = A ge"2Z' m. The mean square perturbation of atmospheric density derived from this expression

predicts the fading speeds found in practice and may be a useful index for determining the safety fading factor. --C. E. P. B.

A-842 Mirick, C. B. and Hentschel, E. R. , A new method of determining height of the Kennelly-Heaviside layer. Institute of

Radio Engineers, Proceedings, 17(6): 1034-1041, June 1929.

13 figs. , table, 4 refs. , 2 eqs. DLC--Radio signals, transmitted by airplanes in flight, are recorded graphically on a moving chart to show periodic variations of frequency over con- siderable time intervals. By connecting this frequency with

the distance of transmission, the ground speed of the aeroplane and the effective height of the K-H layer, a theory is ev- olved by which the height of the K-H layer is computed.

A-843 Mitra, A. P. (Univ. of Calcutta), The D-layer of the ionos - phere. Journal of Geophysical Research, 56(3): 373-402, Sept.

1951. 10 figs. , 5 tables, 35 refs. , 15 eqs. MH-BH--Normal

(75-90 km) and sporadic (60 km in tropics) D layers are described on the basis of present knowledge, and effects on long

and short wave radio propagation and reflection discussed.

Theories of origin include that of MITRA, BHAR and GHOSH

(UV ionization of 02), JOUAST and VASSEY (photo-ionization

of atomic sodium) and NICOLET (O2, Na and NO ionization);

theories of the D layer structure include models by Bremmer,

Rydbeck, Booker, Wilkes, Stanley and Pfister, which are used

in calculations. In spite of widely differing theories of above

workers, the temperature profile up to 100 km is fairly wellestablished and the composition of the atmosphere uniform, so

a detailed picture of the ion or electron density distribution,

its variation with time, place and height, and the variation of

the effective height of reflection with solar zenith angle can

be presented. The conclusions drawn from the elaborate
248

statistical and graphical models presented here, are: 1) the

electron distribution in no way follows the Chapman law since

the electron distribution increases continuously with height

up to the E layer, the ion distribution does show a similarity

to the Chapman distribution; 2) the variation of reflecting height with zenith angle for long waves can be explained on the

basis of the ionization distribution; 3) the theoretical reflection coefficient at low frequency ranges agree with experimental results, and 4) quantitative results based on observation

confirm that the D region is produced by ionization of the 02

at the first ionization potential. --M. R.

A-844 Mitra, A. P. , Some relationships between the Fl and the F2

regions of the ionosphere. Pennsylvania. State Univ. Ionosphere Research Laboratory, Contract AF 19(604) -1304, Scientific Report No. 79, Nov. 30, 1955. 26 p. 12 figs. , table,

10 refs. , 9 eqs. --In this report analysis of the fluctuations in

the height and electron density of the Fl and the F2 regions

of the ionosphere, initiated in an earlier work (Scientific Report No. 53; also Indian J. Phys. , 28, 269, 1954), is continued. Although the work was originally undertaken to as- sess the merit of the hypothesis of the common origin of the

F layers, it became obvious at a later stage of the analysis

that the close relationship that undoubtedly exists between

the two regions is predominantly of dynamical origin. If fluctuations of solar origin exist, they must be small. A remarkable feature of the fluctuations at Washington is that, both

for electron density and height, the percentage variations in

the F2 region are, on the average, about four times as large as those in Fl. The same relationship is maintained for var- iations associated with geomagnetic disturbances. For both

regions the daily variations of height and electron density are closely related, but an increase in height is associated with

a decrease in electron density and vice versa. For 3-day run- ning averages of the indices, the relationships between the

heights and electron density in the two regions are given by:

P(NmF2) = - 1.3P(h'F2) - 0. 6 P

2

(h'F2)

P(NmFl) = - P(h'Fl)

--Author's abstract.

A-845 Mitra, A. P. , The Indian programme for the International Geophysical Year, Pt. I, Some results of the programme on ionosphere. Journal of Scientific and Industrial Research, Ser. Af 17(10):395-401, Oct. 1058. 7 figs. , 2 tables, 4 refs.
249

A-846 Mitra, A. P. (Ionosphere Res. Lab., Penn. State Univ. ), Time and height variations in the daytime processes in the

ionosphere. Pt. 1: A noontime model of the ionosphere loss

coefficient from 60 to 600 km over middle latitudes. Journal

of Geophysical Research, Wash., D. C, 64(7): 733- 743, July

1969. 4 figs. , 6 tables, 29 refs. , 31 eqs. DLC-This work

deals with the height variations of the various dissipative processes occurring in the ionosphere over a height range of 50

to 600 km, and is an extension of the earlier work by Mitra

and Jones (1954). An expression is given for the calculation

of the loss coefficient over the entire ionosphere. For noon

conditions, defined by the hours 1030 to 1330 LMST, and for

stations in the northern middle latitude zone, the equation

for the loss coefficients for heights in the range of 50 to 600

km is

& = 5 X 10"21

n (02

) + 3 X 10"20

n (0)

2X10'19n(02

) 3

2 X 10" i:L n (02

) + 1 X 10"8 No

-Author's abstract.

+ 1 X 10' "^ cm°/s

A-847 Mitra, A. P. , Relaxation time of the ionosphere. Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF 19

(604) -3875, Scientific Report, No. 119, April 1, 1959. 35 p.

13 figs. , 4 tables, 17 refs. , 33 eqs. DWB (M10. 535. P415i

No. 119) --A generalized study of relaxation time phenomenon

comprises the subject of interest of this report. A new model

based on extensive experimental data, is deduced and is re- lated to the physical considerations involved. Temporal and

latitudinal variations are included in this study to the extent

possible. The report is concluded with a discussion concerning several related phenomena. --Author's abstract.

A-848 Mitra, S. K. (Univ. of Calcutta), General aspects of upper

atmospheric physics. (In: Compendium of meteorology. Boston, American Meteorological Society, 1951. p, 245-261.

7 figs. , 3 tables, 108 refs. ) MH-BH--Effect of radiation and

turbulence on structure of the atmosphere is first considered.

Then the outer limit of the atmosphere, the escape of gases

(cone of escape), problem of deficiency of helium in atmosphere, the exosphere or fringe region (similar to corona of sun),

the solar control of upper atmosphere, effect of solar UV radiation on various atmospheric gases, geometry of illumination of

upper atmosphere by sun, etc. accompanied by models and tables, are discussed. Methods of investigation or exploration
250

are next considered. Direct methods (balloon, smoke shell,

V-2 rocket, sound and radio), and indirect (meteors, auroras,

night sky light, magnetic variations, barometric oscillation,

noctilucent clouds and scattering of UV light) are considered

systematically. —M. R.

A-849 Mitra, Sisir Kumar (Univ. of Calcutta, India), General as- pects of upper atmospheric physics. U. S. Air Force. Cambridge Research Center, Geophysical Research Papers, No.

11:19-54, 1952. 6 figs. , 3 tables, 22 refs. DWB-As an introductory speech for the Conference on Ionospheric Physics,

PROF. MITRA outlined in detail our knowledge of the upper

atmosphere in all of its ramifications, and presented a number of problems for future study. The escape of gases in the

fringe region, illumination, meteor trails, auroras, radio wave

soundings, solar and cosmic radiation effects, ionization, luminescence, winds, effect on weather conditions in the troposphere (and vice versa), extent of the atmosphere, normal state

of pressure and temperature, etc. are discussed and many as- pects illustrated. --M. R.

A-850 Mitra, Sisir Kumar, (Symposium on) the physical characteris - tics of the upper atmosphere. U. S. Air Force. Cambridge Research Center. Geophysical Research Papers, No. 12:21-39,

1952. 2 refs. DWB--The discussion dealt with some unsolved

problems, such as: 1) the height of the atmosphere where the

diffuse separation begins, 2) the temperature in and above the

E layer regions, 3) the distribution of atomic nitrogen, 4) origin of the F2 layer, 5) the nature of the ionized regions res- ponsible for the sporadic E, Es, 6) origin of the winds at the

E and F layer heights, 7) origin of the sodium in the upper atmosphere and 8) the correlation between weather and the ionosphere. Although the topics were but briefly discussed, many

theoretical considerations and suggestions were given by the

contributors. --W. N.

A-851 Mitra, Sisir K. , The upper atmosphere. 2nd ed. Calcutta,

The Asiatic Society, (Preface 1952. ) 713 p. figs. , tables,

bibliog. p. 644-668, eqs. DLC, MH-BH-The purpose of the

book, as stated in the first edition issued 1947, is to give,

"in a connected form, an account of the present state of our knowledge of the upper atmosphere as has been obtained so

far by direct and indirect observations. " The 2nd edition contains 13 chapters and an appendix and the bibliography of 887

items is arranged in that order. Author, source and imprint

are given but no titles. Ch. VI, The ionosphere (p. 176-353),

is a comprehensive survey covering history, propagation of

electromagnetic waves, radio sounding of the ionosphere, absorption, application of ionospheric data to radio transmission,
251

origin and stratification, variations, irregularities and disturbances and, finally, weather and the ionosphere. There

are 294 references for Ch. VI (p. 649-656). Imprints cover

the period 1902-1951. --M.L. R.

A-S52 Mitra, S. K. , The story of radio-electronics. Journal of Scientific and Industrial Research, Sec. A, New Delhi, 14(1):

3-13, Jan. 1955. 6 foot-notes (incl. 3 foot-refs. ). DWB--This

presidential address to the 42nd Session of the Indian Science

Congress, Baroda, Jan. 4, 1955 opens with a brief summary of

radio electronics from fundamental research to practical applications in radio climatology, radio astronomy and defense.

Next part takes up India's position in radio research, facilities and future. It ends with an appeal to the younger generation to take advantage of study facilities in the nationally important field of radio electronics. --W. N.

A-853 Mitra, S. N. , A radio method of measuring; winds in the iono- sphere. Institution of Electrical Engineers, Proceedings, Pt.

3, 96(43): 441-446, Sept. 1949. 10 figs. , 14 refs. , 8 eqs.

DLC--An important article describing apparatus, theory, methods of observation and comparing results with those of others.

By using a 4 Mc pulse transmitter and 3 receivers about 100 m

apart, 32 determinations of winds in the ionosphere were made.

Frequency of speeds ranging from 20 to 120 m/sec, shown on

histograms. Greatest frequency at about 50 m/sec, and from

the SE (shown in polar histogram as toward NW). Diurnal var- iation also shown graphically (evidence of semidiurnal period).

As results indicate no winds of this magnitude in F-region,

these observations are assigned to the sporadic E-region (70-

115 km). Results agree with those obtained from luminous phenomena (meteors and luminous clouds) by other workers but

not in agreement with theory. --M. R.

A-854 Mitra, S. N. (New Delhi), Effect of ionospheric irregulari - ties on the variations of phase-path and amplitude of a downcoming wireless wave . Journal of Scientific and Industrial

Research, India, 11(11) :453-454, Nov. 1952. fig., 2 refs.--

Brief discussion of the results of simultaneous record change

of the phase-path and the variation of the amplitude of the same

downcoming wave. A pulsed transmitter of about 2 Mc/s was

used. A typical example of the reflection from the normal Elayer is presented on a 35 mm film strip. According to the

author's conclusion amplitude variations and phase discontinuities are due to the motion of an "irregular ionosphere".

--W. N.
252

A-855 Mitra, 8. N. and Mazumdar, S. C. , Some measurements of

ionospheric absorption at Delhi. Journal of Atmospheric and

Terrestrial Physics, 10(l):32-43, Jan. 1957. 7 figs. , 2 tables, 18 refs. , 12 eqs. DWB--Measurements of ionospheric

absorption on 5 and 2. 5 Mc/s in June 1954-Dec. 1955 are described. Experimental set-up is shown; it gave log P where P

= (electric field of reflected polarized wave)/(electric field of

corresponding incident wave). Diurnal variation gave /log P

/OC (cos X) where n varied from 0. 33-1. 13, mean 0. 62. Relaxation time averaged 45 min. Difference from theoretical

values n = 1. 5 and 8 min. is attributed to the main absorption taking place in the D region. Results of observations

after sunset are not clear, but the high residual absorption

at night may be due in part to ionization by corpuscular solar

emissions. --C. E. P. B.

A-856 Miya, Ken-ichi (Central Radio Wave Observat. R. R. C. ), Consideration on the measurement of vertical incidence ionosphere attenuation in high frequency. Japan. Science Council. Ionospheric Research Committee, Report of Ionosphere in

Japan, 5(4): 201 -202, 1951. 7 eqs. DWB--A short note about

the calculation of the ionosphere attenuation using the difference between field intensities of the "one hop and two hop"

reflection waves observed simultaneously. The result coincides with the result obtained by means of the conventional

method, using the field intensity of the "one hop" reflection

wave. --A. A.

A-857 Miya, Ken-ichi and Kanaya, Sumio (both, Kokusai Denshin

Denwa Co. , Ltd. ), Radio propagation prediction considering

scattering wave on the earth's surface. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 9(1):1-15, March 195J. 12 figs., 2 tables,

15 refs. DWB, DLC --Control-point method is usually employed

in the prediction of the behavior of radiowave propagation in

long-distance radio communication channels. For a particular

channel, however, this method often gives results considerably discrepant with observation. With the intention of improving the percentage of successful prediction, this paper

deals with the investigation of the method of applying the

scattering waves on the earth's surface to the prediction of

radio-wave propagation conditions. A new method called "control-line method" is proposed to determine the MUF with regard

to the scattering waves from the land and from the earth's surface. The new and the old methods are applied to various radio communication channels and the theoretical and observed

results are compared. It is found that for commercial shortwave bands below 20 Mc/s, only normal and land-scattered

propagations can be taken into account for satisfactory pre-
253

diction. Next, the method of calculating the LUF is investigated. Numerous examples show that the new MUF and LUF

give prediction that hits fairly good to radio circuits between

Europe and Japan. Finally, the method of the LP. S. of Australia, which is aimed at correcting the errors of the prediction

of propagation conditions, is discussed from the authors' point

of view. --Authors' abstract.

A-858 Miya, Ken-ichi and Kanaya, Sumio (both, Kokusai Denshin

Denwa Co. , Ltd. ), On the lateral deviation of radio waves

coming from Europe. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan,

10(1): 1-8, 1956. 8 figs. , table, 3 refs. , 3 eqs. DWB--The

gain of receiving rhombic antennae pointing in various directions was measured in Tokyo on waves coming from Europe.

Lateral deviation was observed often followed by comparatively strong field intensity in the untransmissible period of the

normal F2 propagation. From the results, the following two

propagation modes are suggested for interpreting the propagation of the wave of frequency above F2-4000-MUF. One of

them is the forward continental scatter by the F2 propagation

off the great circle and the other is the forward ground scatter

reflected by sporadic E clouds near the great circle covering

the region of low MUF. —Authors' abstract.

A-859 Miya, Ken-ichi; Ishikawa, Masaru and Kanaya, Sumio (Tokyo),

On the bearing of ionospheric radio waves. Japan. Science

Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 11(3): 130-144, Sept. 1957. 11 figs.

,

13 refs. , 5 eqs. DW6--This paper describes fluctuation and

remarkable lateral deviation of bearing of the ionospheric HF

waves, measured by using a new visual and recording type

direction finder. As regards fluctuation of bearing, the relation between propagation mode and distance is explained.

Three cases of lateral deviation are pointed out according to

propagation modes of ground back scattering,cont inental forward scattering and antipodal propagation, and characteristics

thereof are clarified. It is shown, in particular, that lateral

deviation of the continental forward scatter is observed on a

radio circuit in which the propagation mode is predominant and

at times when the MUF on the great circle is lower than the

frequency used. --Authors' abstract.

A-860 Moeller, H. G. , Further results of sweep frequency obligue

incidence experiments. Journal of Atmospheric and Terrestrial

Physics, 13(1-2):173-, Dec. 1958. ref.

A-861 Mook, Conrad P. , A preliminary meteorological study of the

origin of whistlers . Journal of Geophysical Research, 64(7):

745-748, July 1959. fig. , 11 refs.
254

A-862 Morgan, M. G. , A review of VHF ionospheric propagation.

Institute of Radio Engineers, New York, Proceedings, 41(5):

582-587, May 1953. numerous foot-refs. DWB-Five phenomena which make it possible for very high frequency signals

(30-300 mc) to be propagated between two points on the earth

by passing through the ionosphere are discussed. These are:

1) regular F2 ionization, 2) sporadic E ionization, 3) scattering from the regular ionization, 4) auroral ionization and 5)

meteoric ionization. The paper is based mainly on information available in the U. S. and Canada. --G. T.

A-863 Morgan, M. G. (Dartmouth College), A review of VHF ionospheric propagation. Institute of Radio Engineers, N. Y.

,

Proceedings, 43(6): 752, June 1955. DLC--Note about reception at Whyalla, S. Australia, of 39 Mc police transmissions

from N. America in Oct. -Dec. 1947 and 1948 between 0800

and 1200 local time, and for 2 or 3 days at 27-day intervals.

The signals were sometimes strong enough to drown out the

FM radio telephone circuit from Crystal Brook, 45 mi away.

It was finally verified that the signals came from S. Dakota

State Police or from nearby states or provinces of Canada,

and the police in S. Dakota reported hearing Australian stations during the same period (reports not verified). Period

came at sunspot maxima and at 11:30 to 15:30 at mainpoint

of S. Dakota-S. Australia path (Fanning Island). —M. R.

A-864 Morgan, M. G. , Whistlers and dawn chorus. International

Geophysical Year, 1957/1958, Annals, 3:315-336, 1957. 8

figs. , refs. DWB--A detailed account of the available information on methods of measuring whistling atmospherics is

given as supplementary material to the article by F. HORNER

After a general description of the phenomena involved, the following topics are covered with a view toward

standardization of measurement observations, equipment, etc.

1) IGY objectives; 2) Equipment and observing techniques (general, antennae, cathode input, dynamic range, filters, antenna

siting-hum, oscillation, calibration, and recording technique)

;

3) Data reading and presentation (general, spectrographs, wave

form analysis); and 4) A minimum station. A series of appendices includes an analysis of tweeks, notes on the earth's

magnetic field and on multiple whistlers, and sample tables

of subjective data which were recorded as the result of var- ious observations. --R. P.

A-865 Morris, D. W. and Hughes, C. J. , Phase characteristics of

radio signals received via the ionosphere. Nature (London),

183(4657) :310-311, Jan. 31, 1959. 2 figs. , 6 refs.
255

A-866 Motzo, M. (Radiopropagation Studies' Center, Inst, of Techn.

Physics, Univ. of Naples), Curve teoriche di risonanza nell.

interazione tra onde elettromaanetiche. per incidenza vertic ale

nella ionosfera. (Theoretical curves for gyrointeraction between

electromagnetic waves crossing the ionosphere at a vertical incidence. ) II Nuovo Cimento, Ser. 9, 9(3):213-219, March 1,

1952. 3 figs., 2 tables. English summary p. 219. DLC-It

is pointed out that V. A. BAILEY developed a theory for calculating the gyrointeraction between two electromagnetic waves crossing the same ionospheric region, one of them having

an oblique incidence. The theoretical curve representing this

phenomenon is presented. The author offers a similar curve

for gyrointeraction between successive waves crossing the ionospheric E-layer at a vertical incidence. This method is claimed to be more practical for experiments. Values for intensity

of the electromagnetic field of the disturbing wave and for the

index of interaction are tabulated. --G. T.

A-867 Muller, Hans Gerhard, Ein neues elektrisches Hohenwindmessverfahren. (A new electrical wind aloft measuring device.

)

Germany, Reichsamt fur Wetterdienst, Forschungs- und Erfahrungsberichte, Ser. B, No. 20, 1944. 16 p. 15 figs. , 4 tables,

7 refs. Photostat. (Formerly Germany secret. ) DWB--An ultra

short wave station on the ground sends out an impulse which

is reflected from the balloon apparatus, giving the elevation

and azimuth angle on the receiver. - The principle of the device, evaluation of records, calibration, errors and results

are described and compared with other types of equipment in

common use. --M. R.

A-868 Mullaly, R. F. , Graphical constructions for ray-tracing in the

ionosphere. (In: Physical Society, London, Physics of the

Ionosphere, Pt. 4, The mathematics of wave propagation through the ionosphere. London, Physical Society, 1955. p. 384-

393.)

A-869 Mullaly, R. F. , The calculation of group velocity in magnetoionic theory. Journal of Atmospheric and Terrestrial Physics,

9(5/6) :322-325, Nov. 1956. 10 refs. , 15 eqs. DWB--It is

shown how the magneto-ionic group refractive index /6 may be

calculated as a function of the direction of propagation O by

expressing both these quantities in simple form in terms of a parameter A , which is given a series of values. A similar

method gives ju' as a function of the electron density for a fixed value of O. Whereas most computations of/u made up

to the present have required electronic calculating machines,

the simplified formulae given here are suitable for use with a desk calculator. Throughout, the effect of collisions in the

medium is neglected. —Author's abstract.
256

A-870 Munro, G. H. , Short-period changes in the F region of the

ionosphere. Nature, London, 162( ):886, 1948. --Continuous

ionospheric observations at 3 sites at distances 13, 27 and 30

miles apart, indicate horizontal motions in region F2 with velocities between 3 and 5 miles/min. The effects observed may

be due either to horizontal drifts in the ionosphere, with superimposed local variations in ionization gradient, or to a progression of a wave motion (e. g. a pressure wave). The evidence presented is considered to favour the latter explanation.

A-871 Munro, G. H. (Elec. Engi. Dept. , Sydney Univ. ), Travelling ionospheric disturbances in the F region. Australian Journal of Physics, Melbourne, 11(1):91-112, March 1958. 21

figs., 8 refs. DLC--Observations of the horizontal movements

of travelling ionospheric disturbances recorded on a single

radio frequency from April 1948 to March 1957 are analyzed

for seasonal and diurnal variations of occurrence and of direction and speed of travel. Recording was mainly in daylight

hours but some limited night results are included. The aver- age number of disturbances recorded was six per day over the

period. Observing accuracy and significance of the deduced

data are discussed. The frequency of occurrence has a diurnal

variation with a marked midday maximum and a seasonal variation with minima at the equinoxes. The monthly means of direction of travel show a consistent seasonal change from 30 in

winter to 120 in summer with a small corresponding change in

mean speed from 8 km/min in winter to 7 km /min in summer.

The monthly mean diurnal variation of directions was consistent from 1950 to 1954 but has shown a marked change in the

last two summers. Winter directions by day are mainly in the

north-east quadrant and have a mean day-time drift towards

the north but at night they are predominantly in the north-west

quadrant. Summer day-time directions were mainly in the southeast quadrant until Dec. 1956; since then they have tended to

the south-west after noon, reverting to the south-east about

midnight. Diurnal variation of speed is of the same order as

the seasonal change. --Author's abstract.

A-872 Munro, G. H. , Reflexions from irregularities in the ionosphere. Royal Society of London, Proceedings, Ser. A, 219(1139):

447-463, Oct. 7, 1953. 12 figs. , 6 refs. DLC--Gives results

of a 4-year study at Sydney, Australia, of small daytime changes in virtual height of F region reflections with periods of 10

min-1 hr on 5. 8 Mc/s, using 3 pulse transmitters 50 km apart.

Disturbances are classed as X (loop), Y (branch) and Z types.

The complexities are special cases of reflection from curved

surfaces, associated with travelling disturbances, and occur

frequently. The differences of type result from different group

retardations along different paths. --C. E. P. B.
257

A-873 Munro, G. H. and Heisler, L. H. (both, Electrical Eng.

Dept. , Univ. of Sydney), Divergence of radio rays in the

ionosphere. Australian Journal of Physics, Melbourne, 9(3):

359-372, Sept. 1956. 10 figs. , table, 9 refs. , eqs. DLC--

Travelling disturbance manifestations on ionosonde records

usually occur at different times on the "o" and "x" traces. It is shown that this is due to the divergence of the ordinary and

the extraordinary rays in the earth's magnetic meridian plane

and that the sense of this time difference, therefore, gives a direct indication of the sense of the north-south component of

movement of the disturbance. Furthermore, where the direction and speed of travel of a disturbance can also be determined from spaced station observations, the actual separation

of reflection points of the o- and the x-rays can be deduced.

At Sydney, N. S. W. (33°52'Sf 151°11'E) this is of the order

of 30 km at the height of maximum ionization of the F2 re- gion. On h't records the corresponding time difference observed includes a component due to the vertical separation of re- flection points if the front of the disturbance is not vertical.

From records of this type taken at three spaced stations the

horizontal component may be determined directly. Examination of some 430 such observations taken over a period of 4

years confirms the variation of the time difference with direction of travel predicted by theory, and also indicates the consistent presence of a forward tilt in the front of disturbances.

The theoretical relation between the horizontal and vertical

separation is then used to determine the slope of front of disturbances. It is found to have a mean value varying from 65

to the horizontal for disturbances travelling northward to a minimum of 51 for those travelling 120 E of N. --Authors' abstract.

A-874 Murty, T. V. S. (Banaras Hindu Univ. , Banaras, India),

Design and development of a simple ionospheric equipment.

Journal of Scientific and Industrial Research, Sec. A, New

Delhi, 15(2):70-74, Feb. 1956. 9 figs. , 12 refs. DWB, DLC

--A compact and simple manually operated medium power ionospheric sounding transmitter and receiver was constructed in

the Banaras Univ. laboratories. The design and circuits, re- cords and sensitivity and selectivity curves are illustrated.

A cathode-ray oscillograph is used for reproducing the pulses.

Scattering of radio waves can be studied by means of the pul- ses. --M. R.

A-875 Nagata, T. and Abe, S. (Geoph. Inst. , Tokyo Univ. ), Notes

on the distribution of SC* in high latitudes. Japan. Science

Council. Ionosphere Research Committee, Report of Ionosphere

Research in Japan, 9(l):39-44, March 1955. 4 figs. , 7 refs.

DWB, DLC--
258

Distribution of the preliminary reverse impulse ( ^ Hk) of SC*

of magnetic storms in the Northern Hemisphere is examined.

The result shows that the equivalent overhead currents for

-£». Hk are represented by current flows from 10 h to 22 h in

the Polar Cap and the resulting two vortices extending to lower latitudes; a clockwise vortex in the afternoon and a weaker

counter-clockwise one in the forenoon. --Authors' abstract.

A-876 Naismith, R. , Improved chart for ionospheric forecasting in

the British Zone. Institution of Electrical Engineers, London,

Proceedings, Pt. B, 102(4): 503-504, July 1955. 2 figs. , table. DLC--An improved form of chart for use in ionospheric

forecasting is described. In the international 3-zone system

of presenting forecasts of radio-wave transmission conditions,

the necessity to provide average values over a range of longitudes introduces errors. These errors can be eliminated for

the region of the United Kingdom by the use of a British Zone

Chart (B. Z. C. ), which presents the predictions directly for

all 2, 000 km control points around London. A comparison by

various user organizations show that, over a test period of

six months, the standard deviation between the predicted and

observed conditions was approximately halved when the B. Z. C.

was used. --Author's abstract.

A-877 Nakai, Taketosi, The distance of the source and the height

of reflection deduced from the waveforms of ionospheric reflection type. Nagoya. Univ. Research Institute of Atmospherics,

Proceedings, 4:20-28, Dec. 1956. 6 figs. , table, 2 refs. DWB

--The effective height of reflection (h) in the ionosphere and

the distance of the source (d) were estimated by the reflection

theory in the use of the waveforms of the regular peaked type

observed in Toyokawa in June, 1950; h is found to be about

85 + 5 km and d is estimated to the accuracy which is approximately proportional to the reciprocal of the distance of propagation. The derived values for d were compared with good

quality C. R. D. F. Fixes and the results showed fair agreement. These results are described in this paper, but particular emphasis is given to a possible range of solutions for h

and d deduced by a graphical method of analysis or deduced

from the reflection theory and it is discussed that practicability of estimating h or d to a useful accuracy from the waveforms reflected in the ionosphere depends on the distance itself or the number of recorded echoes and the discrepancies

which occur between the recorded and ideal sequence of echoes.

--Author's abstract.
259

A-878 Nakai, Taketoshi, Atmospheric noise study by measurement

of the amplitude probability distribution. Nagoya Univ. Research Institute of Atmospherics, Proceedings, 5:30-49, March

1958. 21 figs. , 3 refs. , 10 eqs. DWB--The cumulative probability of amplitude in the envelope of atmospheric noise was

measured at the output of a narrow-band receiver at 50 kc/s.

The level of integrated atmospherics was recorded at the output of the receiver at the same frequency. The band width of

the receiver was about 1, 000 c/s. The departure from a single

logarithmic -normal distribution was investigated. Type of the

amplitude distribution is described. A description is given of a calculation which was made to determine the effect that the

departure from a single logarithmic -normal distribution has on

the total noise power. The curves derived from this calculation may provide a useful means in estimating the R. M. S.

value of the noise amplitude. The description is given of a calculation which was made to investigate the behavior of

short-time fluctuations of the probability measured. The re- sults may provide a means of estimating a pulse spacing of

the larger amplitude. Various parameters have been derived

from the amplitude distributions. These parameters are described and the diurnal change of each parameter is shown, and

the level of integrated atmospherics is compared with the

R. M. S. value derived from the amplitude distribution. --Author's abstract.

A-879 Nakai, Taketoshi and Suzuki, Y. , Atmospherics noise study

at 50 kc . Nagoya Univ. Research Institute of Atmospherics,

Proceedings, 6:22, Jan. 1959.

A-880 Nakata, Yoshiaki; Kan, Miyao and Uyeda, Moroyuki, Simul - taneous measurement of sweep frequency h't and fct of the ion- osphere. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere in Japan, 7(4): 129-135, Dec. 1953.

6 figs. , 3 refs. , eq. DWB--This paper deals with simultaneous

continuous recording of virtual height and critical frequency of

the ionosphere, by changing the frequency in the band from 4. 9

to 9. Mc/s. The adopted equipment is briefly described.

Sample records are presented. --Author's abstract.

A-881 Napoletano, Aldo, Richerche di correlazioni ionosfericometeoroloqiche . (Research on ionospheric -meteorological cor- relations. ) Rivista di Meteorologia Aeronautica, 10(3):18-22,

July-Sept. 1950. 3 figs. , Italian, French, English and German

summaries p. 18. MH-BH--A survey of research on correlation

between ionospheric and meteorological conditions since 1932

is followed by a series of graphs, showing relation between

mean pressure and hours of maximum ionization of the F2 layer

(according to Mihran) and of E layer variations and Wolf number
250

as obtained at the Central Radiopropagation and Radionavigation Laboratory in Naples. Research now in process there

is outlined. --M. R.

A-882 National Research Council. United States National Committee on International Scientific Radio Union (ISRU), Report on

the 12th General Assembly. Aug. 22-Sept. 5. 1957. Boulder.

Colorado. National Research Council, Publication, No. 581,

1958. 195 p. figs. Mimeo. DWB (621. 384 N277re), DLC

(TK5700. 1834). This report on General Assembly also issued

in Institute of Radio Engineers, Proceedings, 46(7): 1350-1383,

July 1958. —The 7 reports cover: 1) Radio measurements and

standards by Ernst Weber; 2) Tropospheric propagation by John

B. Smyth; 3) Ionospheric propagation by L. A. Manning; 4)

Radio noise of terrestrial origin (sferics and whistlers) by Harold E. Dinger; 5) Radio astronomy by F. T. Haddock; 6) Radio

waves and circuits by E. C. Jordan; 7) Radio electronics by

W. G. Shepherd. Reports of Commissions 2, 3, 4 and 5 will

be abstracted separately. The 12th General Assembly of

U. R. S. I. at Boulder was attended by over 500 radio scientists

from 26 countries. The reports provide an excellent summary

of work going on all over the world in each field. The agenda

for the 7 sessions is given on p. 1350-1 by Frederic H. Dickson and U. R. S. I. and its officers and chairman is discussed

on p. 1351-2 by H. W. Wells. The address of welcome by

Detlev W. Bronk, President of the National Academy of Sciences, appears on p. 1352-4. The extensive report to the

Academy of Science contains notes on attendance, program,

detailed transactions of the assembly, symposia and business

sessions, documents, discussions, resolutions, etc. --M. R.

A-883 Nawrocki, P. J. , Investigation of atmospheric radio noise . Florida. Univ. , Gainesville. Engineering and Industrial Experiment Station, Contract AF 19(604) -876, Scientific Report,

No. 13, Nov. 1, 1956. 35 p. 13 figs. , 8 refs. , 22 eqs. DWB

(M94. 6 F636i) --Investigation of the electromagnetic field components (E 2 and H2) of the ground wave from individual sferic

pulses exceeds the theoretical value obtained from SOMMERFELD's theory, and that H2 and E2 probably have a common

functional dependence upon the distance of propagation. --Author's abstract.

A-884 Nearhoof, H. J. (Penna. St. Coll. Ionos. Res. Lab.), Tabu- lation of 150 Kc/s polarization data obtained at vertical inci - dence including their interpretation from the single magnetoionic component viewpoint. Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic

Ionospheric Research, Technical Report No. 25, Aug. 20,

1951. 418 p. 23 figs. , tables, 14 eqs. DWB--
231

Theoretical methods are discussed which allow the determination of the electron density and the collisional frequency from

the measurable polarization quantities as defined by the Appleton-Hartree equation. These methods are general in that

they can be applied to any geographical location and to any

operating frequency. Experimental results on 150 Kc/s are then interpreted using the above mentioned theoretical procedure by treating the downcoming echo as a single magneto

ionic component. The results are then applied to an assumed

ionospheric model of Chapman shape and with an exponential

V curve fixed in space and independent of time. --Author's abstract.

A-885 Nertney, R. J. (Penna. St. College. Ionos. Res. Lab.),

Characteristics of the lower ionosphere as deduced from loner

wave measurements: preliminary. Pennsylvania. State College.

Ionosphere Research Laboratory, Contract AF 19(122) -44, Basic

Ionospheric Research, Technical Report, No. 28, Sept. 20,

1951. 46 + p. 29 figs., 16 refs. , eqs. DWB-The theory of

obtaining wave solutions of ionospheric ally reflected waves

(see Report No. 20 (1), and 27 (2), ) and 150 Kc/s

experimental data were used to determine diurnal and seasonal

characteristics of the lower E and D region. The existence of

certain "splits" may be explained without recourse to a very

sharp strata layer. --W. N.

A-886 Nertney, R. J. , Method for obtaining the wave solutions of

ionospherically reflected long radio waves including all variables and their height variations with preliminary applications.

Pennsylvania. State College. Ionosphere Research Laboratory.

Contract AF 19(122) -44, Basic Ionospheric Research, Technical Report, No. 20, March 15, 1951. 65 + 12 + 8 p. 27 figs.,

2 tables, 15 refs. , eqs. DWB--Applies the "wave theory" specifically to the problem of obtaining the wave solutions of the

uncoupled wave equation for 150 kc at vertical incidence over

State College, Pa. , whereby solutions were obtained for the

"ordinary" component under some specified conditions. Wave

functions for E layer fc = 0. 55, 1. 1, 2. 2, 3. and 4. 4 Mc

and from which the calculations of the reflection coefficients

are made. Extended dispersion calculations (see Report No.

lOvD ) in graphical representations of JU. and X,

ordinal ? and extraordinary waves for fc 3. Mc and the X values on the extraordinary wave for all fc values above are presented. Other calculations are made and the comparison made

between theoretical and experimental results. Postulating a D layer accountable for discrepancies, author presents two Dlayer models. --W. N.
262

A-887 Nertney, R. J. , The lower E and D region of the ionosphere

as deduced from long radio wave measurements. Journal of

Atmospheric and Terrestrial Physics, 3(2):92-107, Feb. 1953.

31 figs., table, 13 refs. Also issued as: Pennsylvania. State

College. Ionosphere Research Laboratory, Contract AF 19(122)-

44, Scientific Report, No. 39, June 20, 1952. 78 p. 35 figs.

,

table, 27 refs. , eqs. DWB--Model electron distributions for

E and D layers are set up, based on experiment and theory, for

noon (summer) and for night. Conclusions from models are compared with observed heights of critical layers. --C. E. P. B.

A-888 Netherlands. Meteorologisch Instituut, Het Internationaal

Geophysisch iaar. 1957-1958. (International Geophysical

Year, 1957/1958. ) Its Verspreide Opstellen, No. 4, 1957.

79 p. figs., photos. Contents: VENING MEINESZ, F. A.:

Aloemene inleiding (Introduction), p. 7-16; BLEEKER, W. : Het

budget van de dampkrinq. (Atmospheric budget), p. 17-23;

GROEJN, P.: Het onderzoek van de wereldzee, (Oceanographic

research), p. 25-31; VELDKAMP, J. : De hoogste luchtlagen.

(The upper layers of the atmosphere), p. 33-41; MINNAERT, M.

G. J. : De waarneming van de zon. (Solar observations), p. 43-

48; JONGEN, H. F. : De kosmische straling. (Cosmic rays), p.

49-55; DE VOOGT, A. H. : Het radioverkeer in het Internation- al Geophysisch Jaar. (Radio propagation), p. 57-63; ROELOFS,

R. : Aarde, Maan en sterren, (The earth, moon and stars), p.

65-70; OORT, J. H. : Kunstmatige satellieten. (Artificial satellites), p. 71-79. DWB--This attractive brochure consists of

9 articles on different phases of the IGY, with frequent reference to participation by the Netherlands. The preface is by

C. J. WARNERS, director of the KNMI (Netherlands Meteorological Service). The illustrations vividly depict various IGY

activities. --M. R.

A-889 New York Univ. Institute of Mathematical Sciences. Div. of

Electromagnetic Research, Theory of dissociation and recombination processes in the ionosphere. Contract AF 19(122)-

463, Final Report, June 1956. 10 p. Research reports and

publications on the contract, p. 8-10. --Between March 1950

and June 1956, 25 reports were issued under this contract and

80% of these were published in scientific journals. Work done

is summarized under several headings: I. Properties of the

ionosphere; II. Many particle scattering problems; III. General scattering theory; IV. Molecular scattering problems; V.

The inverse scattering problems. --M. R.
233

INewell, Homer E. , Jr. , A review oi upper atmosphere research

A-890 from rockets. American Geophysical Union, Transactions, 31

(l):25-34, Feb. 1950. 6 figs. , 34 refs. Abstract p. 25. MHBH--Research on the upper atmosphere with the V-2 and Aerobee rockets is reviewed; including progress in control of flight,

tracking and recovery of instruments and data, and future re- search program of Naval Research Laboratory working together

with the Signal Corps, Air Force and Applied Physics Laboratory. Relation of altitude to pressure and temperature up to

120 km as determined from flights in New Mexico, shown graphically. Solar spectrum, ozone concentration, cosmic radiation, ionospheric and photographic data on cloud formations

are discussed and illustrated. --M. R.

A-891 Newell, Homer E. , Jr. (Naval Res. Lab. , Wash. , D. C. ), International Geophysical Year earth satellite program. Franklin Institute, Phila. , Journal of the Franklin Institute Monographs, No. 2:2-13, June 1956. DWB--Details of Project Vanguard, including instrumentation of vehicle by Navy Research

Lab. , and the 11 ton launching vehicle being constructed by

Glenn L. Martin Co. ; orbit, 3 stage performance, optical and

radio observing program, computational centers and geophysical or astrophysical problems which may be solved by the

earth satellite program are discussed in this article. --M. R.

A-892 Newman, M. M. ; Stahmann, J. R. and Anderson, J. R. (all,

Lightning & Transients Res. Inst. , Minneapolis), Recording

and classification of thunderstorm atmospherics by counter

techniques. (In: Conference on Radio Meteorology, Nov. 9-

12, 1953, Univ. of Texas, Supplement to the Proceedings, V3, pub. 1954. 9 p. 5 figs. , table, ref. ) DWB (M94. 7

C748p. Sup. )--Noises from whatever source or wave length

can be measured by counter analyzers. The rate of rise, amplitude, average level and pulse repetition rate are characteristics which can be measured with some modifications for

sferics over other types of noise. Models of counter analyzers are described and illustrated. Methods of measurement

outlined, correlation with actual reduction in intelligibility

discussed and equipment, records, and results illustrated in

photographs and graphic forms. It covers a wide range of frequency and the results are easy to read and analyze. --M. R.

A-893 Nicolet, Marcel, Effects of the atmospheric scale height gradient on the variation of ionization and short wave absorption.

Journal of Atmospheric and Terrestrial Physics, 1(3):141-146,

1051. 2 tables, 3 refs. , 35 eqs. MH-BH. Also in U. S. Air

Force. Cambridge Research Center, Geophysical Papers, No.

11:263-272, 1952. 2 tables, 6 refs. , 35 eqs. DWB--Author

demonstrates that material progress can be made in the explanation of the ionosphere by extending CHAPMAN's theory to

allow for: 1) increase of the scale height from the D layer and
264

upwards, 2) that the recombination coefficient varies with

height and 3) that the ionizable constituents may have a different scale height from that of the main constituent. --W. N.

i A-894 Nicolet, Marcel (C.S.A. G. I. , Uccle, Belgium), Constitution of the atmosphere at ionospheric levels. Journal of Geophysical Research, Wash. , D. C. , 64(12): 2092-2101, Dec.

1959. 8 tables, 37 eqs. DLC.

A-895 Noonkester, V. R. , Proposed investigation of ionospheric

electron density profile and geomagnetic fluctuations as a function of stratospheric winds . U. S. Navy Electronics Lab.

,

San Diego, Calif. , Research and Development Report NEL/

Report 908, June 5, 1959. 16 p. 2 figs., 72 refs., 16 eqs.

DWB (M(055) U585r No. 908) -More detailed studies are needed to determine the relationship between ionospheric and lower atmospheric circulation. According to the dynamic theory

of ionospheric electrical currents the electron density profile

and magnetic variations at the surface of the earth are functions of the E layer wind and conductivity distribution. This

is illustrated mathematically in this report. It is concluded

that if significant relationships between ionospheric conditions and lower atmospheric circulation can be found its applications to low-frequency radio propagation problems will

be of great value. --Author's summary & N. N.

A-896 North Atlantic Treaty Organization. Advisory Group for Aeronautical Research and Development, Abstracts of lectures at

AGARD Symposium on Polar Atmosphere, Oslo, July 2-8, 1956

(Ionospheric part), issued 1956. Each abstract repaged. footrefs. Tipped in: (Program) of the Symposium. DWB (M 10. 535

N864s)--A mimeographed collection of abstracts or summaries

of 21 papers on ionosphere and related problems as presented

at the (Oslo) AGARD symposium on the Polar atmosphere. -- m M. R.

A-897 Northover, F. H. (Dept. of Math. , Carleton Univ. , Ottawa,

Canada), The propagation of electromagnetic waves in ionized

gases (with special reference to "whistlers"). Pt. 1. Journal

of Atmospheric and Terrestrial Physics, N. Y. , 17(1/2):158-

169, Dec. 1959. 3 refs. , 46 eqs. Pt. 2, Ibid. , p. 170-178.

35 eqs. DWB, DLC—Recent studies lend support to the theory

that whistling atmospherics are caused by lightning flashes,

the electromagnetic energy radiated by these being guided along discrete columnar ionic irregularities which follow approximately the lines of force of the earth's magnetic field. In

Part I the theoretical problems arising are set forth and a general wave theory developed which is first applied to the problem of propagation through homogeneous compound streaming
235

media. In Part II the simplest case of "standard type" propagation along stationary columns is carefully examined, both

for columns with a central ionic surplus and for columns with

a central ionic deficiency. Although both types of column,

when sufficiently well developed, can guide electromagnetic

energy it appears that the former type is a much more likely

mechanism for the whistler propagation than the latter. It is

hoped in subsequent papers to deal with the propagation of

general type disturbances along stationary columns and also

through columns where appreciable axial streaming is taking

place. --Author's abstract.

A-898 Norton, K. A. and Omberg, A. , The maximum range of a radar set. Institute of Radio Engineers, N. Y. , Proceedings,

35(l):4-24, Jan. 1947. 11 figs. , 2 tables, 36 refs. , 70 eqs.

DLC --Formulas to calculate the maximum range of a radar set

are demonstrated here along with several of the factors analyzed on which a given radar set depends for maximum range.

In addition to electronics, etc. , the meteorological elements

involved in radio wave propagation are discussed. --W. N.

A-899 Norton, K. A. ; Rice, P. L. ; Janes, H. B. and Barsis, A. P.

(all, Central Radio Propagation Lab. , National Bureau of Standards, Boulder, Colo.), Rate of fading in propagation through a turbulent atmosphere. Institute of Radio Engineers, N. Y.,

Proceedings, 43(10): 1341 -1353, Oct. 1955. 13 figs. , table,

22 refs. , numerous eqs. DLC --Fading rate is defined to be the

number of times per minute that the envelope of the received

field crosses its median level with a positive slope. This definition of fading rate is equally useful for ionospheric or tropospheric propagation studies. Furthermore, it may be used

with equal facility on short transmission paths where the ground wave component of the received field predominates and on

the longer transmission paths where the scattered component

of the received field predominates. --From authors' abstract.

A-900 Norton, Kenneth A. , System loss in radio wave propagation.

U. S. National Bureau of Standards, Journal of Research, Sec.

D, 63(l):53-73, July/Aug. 1959. 14 figs. , 6 tables, 33 refs.,

79 eqs. DLC, DWB--A summary is presented of the ways in

which the concept of system loss and the closely related concepts of transmission loss, basic transmission loss, propagation loss, and path antenna gain may be used for precise, yet

simple, descriptions of some of the characteristics of radio

wave propagation which are important in the design of radio

systems. Definitions of various terms associated with the concept of system loss are given which introduce a greater flexibility into its use without any loss in precision. It is shown
266

that the use of these added terms and concepts makes feasible

the extension of the use of this method of description to any

portion of the radio spectrum. A more general formula for the

system loss is given which may be used for antennas with an

arbitrarily small separation. Using this formula it is shown

that the system loss between small electric or magnetic dipoles separated by a distance d <K A can be made arbitrarily

small even though the individual antennas have large circuit

losses. Formulas are developed for the percentage of time

that a desired signal is free of interference, and these are used to demonstrate methods for the efficient use of the spectrum. In particular, contrary to general belief, it is shown

that efficiency is promoted by the use of high power and high

antennas and, in the case of a broadcast service, sufficiently

small separations so that there is appreciable mutual interference. An analysis is made of the variance of the path antenna

gain in ionospheric scatter propagation. Methods are given

for the calculation of the transmission loss for the ground wave

and tropospheric scatter modes of propagation through a turbulent model atmosphere with an exponential gradient. Examples

of such calculations are given which cover a wide range of frequencies and antenna heights. Finally, examples are given of

the expected range of various tropospheric point-to-point scatter systems such as an FM multichannel teletype system, a television relay or an FM broadcast relay. --Author's abstract.

A-901 Obayashi, Tatsuzo, On the world-wide disturbance on F2 - region. Journal of Geomagnetism and Geoelectricity, Kyoto,

6(2):57-67, June 1954. 20 figs. , 2 tables, 11 refs. DLC--

World-wide patterns of F2 region disturbance and their development with geomagnetic storm-time are examined with the

help of comprehensive world-wide data on the F2 layer. Charts

showing average disturbance in the F2 region during the main

phases of associated magnetic storms are presented (separately for the Dst (f°F2) and Ds (f°F2) components). A detailed

analysis is made of the development of individual disturbances

in the Northern Hemisphere associated with some typical severe magnetic storms. --From author's abstract.

A-902 Obayashi, Tatsuzo, Movements of irregularities in the E - region. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 9(2): 105-113,

1955. 9 figs., 8 refs. , 3 eqs. DWB--Movements of large

scale irregularities in the E region have been deduced from the

observations of fading patterns of medium radio waves transmitted from the three broadcasting stations spaced about 150

km at the vortices of a right triangle, as received at Hiraiso

situated 350-400 km apart. The speeds and directions of movement are determined by the time difference of each record,
237

which can be observed as the transit of some characteristics

on fading patterns caused by the travelling of large scale ir- regularities from one propagation path to another. Observations were carried on every day from July to December 1954.

The movements appear to have flowed predominantly towards

the west during the night and the east during the morning with

velocities ranging 5-150 m/sec. The examination of the re- sults for NS and EW components for the winter suggests the

presence of the diurnal variation of direction. The average

vector of movements during the night is also found to exhibit

some seasonal change. By comparing the simultaneous re- cords of ionospheric observation (vertical incidence) with the

fading records of three separated points of reflection, we have

found as an example that the moving cloud, which is observed

as very rapid faded fading with the duration of a few hours has

some correlation with the sporadic ionization cloud, and its

turbulent velocities are of the order of 10-15 m/sec. --Author's

abstract.

A-903 Obayashi, T. , Geomagnetic pulsations and the earth's outer

atmosphere. Annales de Geophysique, 14(4): 464-4 74, Oct./

Dec. 1958. 6 figs., table, 16 refs.

A-904 Obayashi, T. ; Fujii, S. and Kidokoro, T. (all, Hiraiso Radio

Wave Observ. Radio Res. Labs.), An experimental proof of

the mode theory of VLF ionospheric propagation. Journal of

Geomagnetism and Geoelectricity, Kyoto, 10(2):47-55, 1959.

7 figs. , 10 refs. DWB--A new spectoscope recording continuously the amplitude-frequency spectrum of VLF atmospherics

has been developed. The receiver sweeps the frequency giving complete coverage of the band of 5 - 7 kc/s repeatedly and

the output is displayed on an intensity modulated cathode-ray

tube, which is photographed on a slowly moving film. Observations have been carried out and it appears that the result

provides an excellent experimental base for the mode theory

of VLF ionospheric propagation. It is found that the frequencyspectrum of distant atmospherics shows a broad intensity maximum around 10 kc/s and decreases its intensity towards higher frequencies with undulating peaks. Marked selective absorption bands appeared in the spectrum are variable according to the time of day, and they might be associated with cutoff frequencies of the waveguide bounded by the earth and the

ionosphere. The solar flare effect on VLF atmospherics propagation is also revealed, which indicates a sudden shift of the

spectrum to higher frequencies owing to the increase of ionization and the lowering of a reflecting height of the ionosphere.

--Authors' abstract.
268

A-905 Obayashi, Tatsuzo, Measured frequency spectra of very-lowfrequency atmospherics. U. S. National Bureau of Standards,

Journal of Research, Sec. D, 64(l):41-48, Jan. /Feb. 1960.

12 figs. , 11 refs. , eqs. DWB, DLC--New spectroscopes re- cording continuously the amplitude-frequency spectra of vlf

atmospherics have been developed. Two receivers cover the

frequency ranges 1 to 10 kc and 5 to 70 kc sweeping the res- pective bands repeatedly, and their outputs are displayed on

intensity modulated cathode-ray tubes which are photographed

on slowly moving film. Observations have been carried out

since June 1958, and it appears that the results provide an ex- cellent experimental basis for comparisons with the mode theory of vlf ionospheric propagation. It is found that the frequency spectrum of distant atmospherics indicates a pronounced

absorption near 3 to 5 kc, a broad intensity maximum around

10 to 20 kc, and a general decrease towards higher frequencies

with undulating peaks. The selective absorption bands appearing in the spectrum are variable according to the time of day

and seasons. These changes may be interpreted loosely as an

ionospheric effect which is associated with the cutoff frequency of the waveguide bounded by the earth and the ionosphere.

The solar flare effect on vlf atmospherics propagation is also

revealed, which indicates a sudden shift of the spectrum to

higher frequencies owing to the increase of ionization and the

lowering of a reflecting height of the ionosphere. --Author's

abstract.

A-906 Obayashi, Tatsuzo (Hiraiso Radio Wave Obs. Radio Res. Lab.

Nakaminato-shi, Ibaragi-ken), Very low-frequency spectra of

atmospherics propagated through the ionosphere. Nature, London, 184(4679) :34-36, July 4, 1959. 3 figs. , 7 refs. DWB--

A more complete experimental proof of the mode theory on very

low frequency ionospheric propagations and on the characteristics of the atmospherics is given. Descriptive and experimental facts are presented from the observations of atmospherics at Ibaragiken, Japan. Typical records are examined. Among the facts that lend support to the mode theory is one on

the relation between the sudden enhancement of atmospherics,

and the sudden ionospheric disturbances. --N. N.

A-907 Obolenskii, V. N. , Meteorologiia. (Meteorology. ) Leningrad. Gidrometizdat. , 1938/1939. 2 vols. v. 1, 639 p. 273

figs. , 53 tables, refs. (at end of each ch. ), 145 eqs. v. 2,

443 p. 207 figs. , 81 tables, 631 refs. , numerous eqs. DWB

--Vol. I comprises a thorough theoretical and practical text on

physical and synoptic meteorology. Vol. II takes up in more

detail the advanced aspects of atmospheric optics, acoustics

and electrical phenomena such as thunderstorm electricity,

radioactivity and its effect on atmospheric ionization,
269

atmospherics, ionosphere, solar radiation and magnetic effects. The chapter on ionosphere (p. 297-309) summarizes

existing knowledge on methods of investigation (radio wave),

results, theory, normal and abnormal investigations, diurnal

and seasonal variations, clouds of electrons and ions, causes

of variations in ionization of different layers, Dellinger effect,

etc. --M. R.

A-908 Obukhov, A. M. , (Inst, of the Physics of the Atmosphere

Academy of Sciences, Moscow), Scattering of waves and

microstructure of turbulence in the atmosphere. Journal of

Geophysical Research, Wash., D. C, 64(12): 2180-2187, Dec.

1959. 7 figs. , 20 refs. , 4 eqs. DLC-The paper deals with

a brief survey of the theory of scattering of waves by turbulent inhomogeneities. Experiments on the study of scattering

phenomena of sound by turbulence in the surface layer of the

atmosphere are discussed. These experiments were carried

out to obtain some information on the turbulent spectrum; their

results are compared with the data of meteorological measurements in the surface layer. Applying the method of scattered

radio waves to the study of turbulence in the ionosphere is discussed. --Author's abstract.

A-909 Ogata, Yoshiharu (Akita Radio Wave Obs. , Radio Res. Labs. ) Observation at Akita of ionospheric drift. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 10(2):91-92, 1956. fig. DWB--An observation was made to determine the velocity of ionospheric drift by

a joint team of scientists from Akita Radio Wave Observatory

and those from the Radio Research Laboratories. Transmitters

were at Tazawa and Akita, both in Japan. Results show that

the E layer nighttime observations yields sufficient data of

median value 50 m/s and a most frequent velocity of 40 m/s,

whereas the F layer observation during the day gave a median

of 120 m/s in each group and a most frequent velocity of 80

m/s. --N. N.

A-910 Oguti, T. and Nagata, T. (both, Geoph. Inst. , Tokyo Univ. ), Model experiments of the screening effect of the ionosphere.

Tokyo Univ. Geographical Institute, Geophysical Notes, 8(1),

Contribution No. 3, June 1955. 7 figs., 8 refs., 13 eqs. DLC

Reprinted from: Japan. Science Council. Ionospheric Research

Committee, Report of Ionosphere Research in Japan, 8(4):171-

184, 1954. --Electromagnetic induction within a thin copper

shell caused by a rapid change in external magnetic field is

measured in order to find the screening effect of the ionosphere. In this report, some experimental results for several

cases of idealized simple distribution of electric conductivity

are dealt with, and the result of the simplest case is compared
270

with that of theoretical calculation. The agreement of the ex- periment with the theory is satisfactory. It seems therefore

that this model experiment is promising for estimating the

screening effect of the ionosphere having a more complex distribution of electric conductivity. --Authors' abstract.

A-911 Ohio. State Univ. Dept. of Electrical Engineering, Antenna

Laboratory, Antennas for ionospheric scatter propagation.

Contract AF 19(604) -1531, Final Engineering Report, Nov. 1,

1955. (AD-88950).

A-912 Ohio. State Univ. Dept. of Electrical Engineering, Antenna

Laboratory, Antennas for ionospheric forward scatter propagation. Pt. II. Contract AF 19(604) -1531, Final Engineering Report, Dec. 31, 1955. (AD-88950).

A-913 Okamoto, Hironobu; Ose, Masami and Aida, Kazuo (all, Radio Res. Labs. , Kokubunji, Tokyo), New type of scattering

echo observed by the shipborne ionospheric sounder over the sea. Japan. Science Council. Ionosphere Research Committee,

Report of Ionosphere Research in Japan, ll(2):50-54, June

1957. 4 figs. DWB--On the first Japanese Antarctic research

expedition (1956-7) from Japan to Singapore to Cape Town to

Syowa Base and return, a new type of ionospheric sounding

echo scattering was observed (as shown on recorder records)

in a region up to 120 km above the surface for h'f records. No

internal or instrumental failure could be found and, as shown

on an hourly graph, a diurnal cycle was predominant (scatter

mostly in daytime). Over-sea, land or ice propagation showed

differences in type of scatter, being weaker over land or ice

than over sea. It apparently is due to tropospheric conditions.

--M. R.

A-914 Oklahoma Agricultural and Mechanical College. Research

Foundation, Operation and evaluation of the beacon triangulation system and the ionosphere beacon system. Contract W28-

099 ac-376, Final Report (pub. after May 1952). 16 p. DWB

--This final report of a project started in Sept. 1947 is a summary of difficulties developed during the tracing of V-2 rockets

and aerobees for upper air research. Lack of personnel, inadquate direction antennas, and poor synchronization of the clocks at the triangulation stations were the main problems. The

best solution would be to replace all four indicators with automatic synchronization and photograph the records at one interrogator station. --A. A.
271

A-915 Olesen, Jens Kirstein (Danish Nat'l. Comm. U. R. S. I. ) and

Rybner, Jefrgen (Royal Danish Tech. Univ.), Slant Es disturbance at Godhavn and its correlation with magnetic disturbance. AGARDograph, Paris, No. 34:37-57, Sept. 1958. 17

figs., footnotes, 11 refs. DWB (629. 1323 N864a) -This

paper describes the characteristics of slant Es as observed

at Godhavn, Greenland. Statistical material is presented

which shows that 'slant Es condition' in the ionosphere normally occurs only during sunlit hours and only associated with

a certain type of magnetic disturbance, the so-called J-disturbance. There is a close correlation between the occurrence

of the two phenomena, both diurnally and seasonally. The

daytime occurrence of slant Es at Godhavn is distinct from

conditions at places like College, Alaska, where slant Es

is a night-time phenomenon accompanied by the occurrence

of aurorae. During slant Es conditions at Godhavn, reflections from the upper part of the E layer and from the F layers

are always disturbed, while the D region absorption is comparatively low. Slant Es waves are usually so weak that the

recorder gain setting greatly influences the distinctness with

which the corresponding trace appears on the records. Certain phenomena have been found which indicate slant Es conditions in the ionosphere although no slant Es trace is visible.

--Authors' abstract.

A-916 Omori, T. and Okumura, Y. (Electrical Communication Lab. ), Results of vertical arrival angle measurement for radio waves

from San Francisco. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan,

7(1) :29, 1953. DWB--Data for seasonal vertical angle measurement for radio waves from San Francisco for June 1951 to April

1952 are presented and analyzed according to the frequency of

the waves received. The vertical arrival angle at Oi Observatory was found to be proportional to F&E/f and FoF2/f where

FoE and FoF2 are measured at the receiving station and f is

the working frequency of the waves received (13. 78, 7. 715,

18. and 9. 49 Mc/s, respectively). --M. R.

A-917 Oriol Cardus, J. , Sondeos ionosfericos. (Ionospheric soundings.) Revista de Geofisica, Madrid, 14(56): 285-312, Oct./

Dec. 1955. 8 figs. , 19 refs. , eqs. DWB, DLC--An ionospheric recording station was established at Ebro Observatory on

March 26, 1955. The history of ionospheric soundings and propagation of electromagnetic waves from Balfour-Stewart (1878)

and Heaviside (1902), Appleton (1927) and others is outlined,

and the basic equations presented and one explained. Application of theory to ionospheric sounding (determination of

height, electron density, magnetic field, etc.) is next reviewed. Notes on the equipment installed at Tortosa, photographs
272

of installations and records made in 1955, and analysis of

records made at Tortosa from May to Sept. 1955, showing

mean hourly variations in E, Fl and F2 layers for each month

together with conclusions as to diurnal, seasonal, and regional variations in height, etc. of the various layers, are presented. --M. R.

A-918 Ortner, Johannes and Egeland, Alv, Ausseraewohnliche Ausbreitunasbedinaunaen fflr ultrakurze Wellen. ( Unusual propagation conditions for very high frequencies radio waves.

)

Archiv der Elektrischen Ubertragung, Stuttgart, 13(10):420-

428, Oct. 1959. 7 figs. , 6 tables, 16 refs. DLC--At the

Kiruna Geophysical Observatory in Kiruna, Sweden (67. 8 N,

20. 4 E) radio waves of Central European VHF transmitters

could be received within the period Feb. 1958 to Aug. 1959.

These quite unusual conditions for frequencies of 90 Mc/s

occurred only five times, and this during the summer months.

It is difficult to find a close relation between geophysical or solar events and these unusual conditions of propagation,

which occurred during geomagnetically undisturbed and disturbed days. Different processes of propagation are discussed:

forward scatter, meteor trails ionization, auroral E layer. A

quite specific sporadic Es layer gives the best explanation for

these unusual receiving conditions. Critical frequencies observed near the reflexion point of the received radio waves

are of the order of the values computed with Appleton-Hartree

formula, assuming an Es propagation. --A. V.

A-919 Ortusi, J. , The propagation of metre and centimetre waves

(Wavelengths between 6 m and 3 cm) . Annales de Radioelectricite, 9(2 ):227, 1954. --Propagation over both direct-visibility and long-distance paths is considered. Characteristics

studied include received power, and the measurements of turbulence fields are considered in appendixes. The results are summarized for convenient use in a series of ten nomograms,

covering received power, transmission equivalent, attenuation, maximum range and effective antenna height.

A-920 Osborne, B. W. , Horizontal movements of ionization in the

equatorial F region. Journal of Atmospheric and Terrestrial

Physics, 6(2/3): 117-123, March 1955. 3 figs. , 14 refs. DWB

--Spaced-aerial observations of horizontal velocity of ionized

particles during day in F region at Singapore gave in Sept. -Oct.

1953 a regular semidiurnal variation from about 52 m/s towards

E at 9 - 12 h LMT to nearly 50 m/s towards W at 15 - 17 h. A

doubtful tendency was found for movement to S at 9 - 15 h. In

Nov. 1953 - Feb. 1954 movements were less regular and mostly towards W from 10 - 18 h. In March - April 1954 variation

was from 40 - 50 m/s towards E at 9 h and 23 h to over 50 m/s

towards W at 17 h. --C. E. P. B.
273

A-921 Osborne, C. B. , Magnetic and radio disturbance. North Atlantic Ocean. Marine Observer, 22(156): 66-68, 1952. DWB--

June 17, 1951, magnetic compass varied several degrees from

gyro compass, during passage of a large sunspot. No radio

signals could be received. Reports on disturbances from Admiralty Compass Observatory, Overseas Telecommunications

Dept. of G. P. O. and Central Forecasting Office, Dunstable,

are included. --C. E. P. B.

A-922 Outsu, Jinsuke and Iwai, A. , Investigation of the presence of

ionized hydrogen in the outer atmosphere using whistler dispersions. Nagoya. Univ. Research Institute of Atmospherics,

Proceedings, 6:44-55, Jan. 1959. 7 figs. , 7 refs. , 4 eqs.

A-923 Paetzold, H. K. , Die ersten kunstlichen Erdsatelliten. (Das

Internationale Geophvsikalische Jahr. XIII). (The first artificial earth satellites (The International Geophysical Year, Pt.

13). ) Die Umschau, Frankfurt a. M. , No. 1:2-7, 1958. 7

figs. DWB, DLC -Details of the first two Soviet satellites,

their trajectories, tracking and variations are discussed, a- long with the first preliminary scientific results. It appears

that atmospheric density at 200-250 km is about double the

value assumed in the past. Radio signals are being received

from satellites far below the horizon which would indicate

that waves are channeled along the ionosphere for some time

before penetrating into the lower atmosphere. --G. T.

A-924 Paetzold, H. K. and Zschorner, H. (both, Max-Planck-Inst.

fur Stratospharenphysik, Weiss enau), R adiobeobachtungen

auf 20 MHz der ersten russischen Erdeatelliten. (Radio observations at 20 Mc/s of the first Russian satellites. ) Telefunken - Zeitung, Berlin, 31(120) :99-104, June 1958. 8 figs.

,

5 refs. French summary, p. 99; English summary p. 104. -- Analysis of the Doppler effects of the 20 Mc/s radio signals

from the Sputniks I and II yielded the horizontal structure of

the ionosphere discussed here. The radio observations were

conducted at the Institute of Stratospheric Physics, Weisenau,

Germany and the optical observations at the Telefunken Triangulation Laboratory, Ulm. The 2-3 min fadings discussed in terms

of the Cotton-Mouton effect and the Faraday effect indicate ex- tension of ionospheric irregularities to 1, 000 - 2, 000 km. The

existence of focussing elements, also horizontally orientated

over 100 - 200 km is plausible. A form of "guidance" due to

ionospheric refraction, rather than scattering, may further the

6, 000 km wave path. Excellent graphs and reproductions of

the original film recordings are given. --W. N.
274

A-925 Paetzold, H. K. (Max-Planck-Institut fur Aeronomie, Institut fur Stratospharen-Physik, Weissenau and T. H„ Munchen),

Die hochste Atmosphare und der Weltenraum. (The highest

atmosphere and the cosmos.) Umschau, Frankfurt a. M. , 59(1):

3-6, Jan. 1, 1959. 5 figs. , table. DLC DK629. 19:550. 3-

The audibility of the Sputnik radio signals of 20 MHz and 40

MHz indicated that the radio waves were refracted in the ionosphere; this is possible only when the electron density does

not fall below a value of 1. 10® electrons/cm3 in the maximum

of the ionosphere at a height of 300 km. At greater altitudes

the electron density diminishes much more gradually than the

atmospheric density. The relative ionization gradually increases with altitude from 0. 05% at 300 km to 7% at 1000 km.

From the Faraday frequency perceptible in the satellite signals

it was possible to compute an electron density of 5. 10^ electrons/cm3 at 500 km. The temporary and irregular fading indicates the existence of ionospheric inhomogeneities. Duration

of fading of several minutes to several seconds indicated horizontal variations of electron density extending from 2000 km

to 100 km. The satellite became inaudible over higher latitudes at relative close distance while from the south it was

audible at great distances; this indicates the influence of the

polar ionosphere which is more disturbed by incursion of cor- pusite clouds than in lower latitudes. The shorter life of the

satellites as a result of deceleration indicates that atmospheric densities above 200 km are higher than hitherto expected.

These higher densities signify higher temperatures in the upper

atmosphere. At 200 - 350 and 1000 km the corresponding temperatures were 800, 2000 and 2500°K. The composition of the

atmosphere comprises a density of 100 nitrogen molecules/cm3

and 1 x 10® oxygen atoms/cm3, and 0. 1% atomic hydrogen at

about 80 km. At 1000 km there are still 10^ H-atoms/cm3 and

at 3000 km 1000 H-atoms/cm3 may be present. At the high

temperatures of the exosphere H-atoms are no longer stable

but evaporate into the cosmos. Atmosphere density is greater

by day than at night; variations in density amounting to a factor of 10 result from a warming up of the high atmosphere. The

frequency of meteorites impinging upon the satellite was 1 meteorite/100n2 sec for meteorites 4 fu. in diameter; with increasing size the frequency diminished by a factor of 10. The cosmic radiation was extraordinarily high; at 1000 km it was 1000

times greater than the normal cosmic radiation. The radiation

particles were protons. The maximum of radiation is apparently at 10, 000 km and above this height it diminishes. The origin of the radiation belt is discussed. --I. L. D.

A-926 Panofsky, H. A. (Penn. State Univ. ), On the structure of

turbulence in electrically neutral, hydrostatically stable layers , (summary only) . Journal of Geophysical Research, Wash. , D.C.

64(12):2195, Dec. 1959. DLC.
275

A-927 Parkinson, R. W. , Second-order wave solutions for critical

and near-critical coupling conditions . Pennsylvania. State

Univ. Ionosphere Research Laboratory, Contract AF 19(122)-

44, Ionosphere Research, Scientific Report, No. 70, Oct. 1,

1954. 61 p. 34 figs. , table, 9 eqs. MH-BH- -Explicit ex- pressions for second-order wave solutions of the general equations of propagation are obtained. Numerical results are included for six ionospheric models chosen to provide critical

and near critical coupling conditions. It is concluded that

the theoretical results show excellent promise of explaining

experimentally observed coupling phenomena; correlation of

theory with experiment, now under way, is deferred to a future

report. --Author's abstract.

A-928 Parkinson, R. W. , The night-time lower ionosphere as deduc - ed from a theoretical and experimental investigation of coupling phenomena at 150 kc/sec . Journal of Atmospheric and

Terrestrial Physics, London, 7(4/5): 203-234, Oct. 1955. 28

figs. , table, 27 refs. , 3 eqs. DWB--Final results of an ex- perimental programme for the investigation of coupling phenomena at 150 kc/sec, which covered a period of some ten months

in all, are presented. Conclusions are obtained, from a comparison of the theoretical results presented in the preceding

paper and the experimental data, regarding the shape of the

night-time D-layer in the coupling region and its seasonal and

diurnal variations. Sunset D-E region models for July and Nov.

1953 are proposed. A theoretical recombination coefficient

model suggested by MITRA (1954a) is then applied in the usual

manner to determine the variation of these models with time of

night. Finally, comparison is made both with the conclusions

obtained from the data on coupling phenomena and with all

other available low frequency data; very good agreement is obtained in all cases. It is concluded that the theoretical analysis satisfactorily explains the experimental observations. -- Author's abstract.

A-929 Parkinson, R. W. , The fading periods of the E-region coup- ling echo at 150 kc/s. Journal of Atmospheric and Terrestrial

Physics, London, 8(3):158-162, March 1956. 3 figs., 11 refs.

DWB--Fading periods of coupling echoes are discussed. Short

period fades (period about 1-2 min) are superposed on longperiod fades (5-10 min upward). The long fades are attributed

to a diffracting screen at 90 km and the short fades to a screen

below this level, but an alternative explanation is a single

screen at coupling level. --C. E. P. B.

A-930 Parthasarathy, R. and Reid, G. C. , Signal strength record- ings of the satellite 1958 S2 (Sputnik HI) at College. Alaska.

Institute of Radio Engineers, Proceedings, 47(l):78-79, Jan.

1959. table, 2 refs.
276

A-931 Pawseyf J. L. ; McCready, L. L. and Gardner, F. F. , Ionos

pheric thermal radiation at radio frequencies. Journal of Atmospheric and Terrestrial Physics, 1(5/6): 261 -277, 1951. 9

figs. , 2 tables, 6 refs. MH-BH--Minimizing man-made radio

noises and atmospherics, the thermal radiation from the ionosphere has been identified and measured. The electron temperature at 70-80 km was found to be 240-290 K. This paper

describes the equipment used and shows how to distinguish

between different noises. --A. A.

A-932 Pedersen, P. O. , Wireless echoes of long delay. Institute

of Radio Engineers, Proceedings, 17(10): 1750-1785, Oct. 1929.

12 figs. , 4 tables, numerous refs. and eqs. DLC--Short radio

waves, A. = about 31 m. , of which the echoes were delayed by

3 min. 15 sec. and 4 min. 20 sec. , have been observed by

J0RGEN HALS, ST0RMER, VAN DER POL and others. Author

is of the opinion that these long delayed echoes are reflections from ionization bands outside the influence of the earth's

magnetic field.

A-933 Penndorf, R. and Coroniti, S. C. (both, AVCO Manuf. Co.,

Boston, Mass.), Polar Es . Journal of Geophysical Research,

Wash., D. C. , 63(4, Pt. l):789-802, Dec. 1958. 10 figs.

,

table, 10 refs. DW6, DLC—Data obtained by ionosondes and

published by CRPL are used to investigate Es over the Polar

region. Three distinct types of polar Es exist, labeled Thule,

Auroral Belt, and Mixed type. The Thule type, which is restricted to the area close to the geomagnetic pole (north of 73

geomag. lat. ), shows a summer maximum occurring around geomagnetic noon. It follows Universal time. The auroral Belt

type occurs along the Auroral Belt and appears only at night.

It follows local time. No appreciable change with season or sunspot activity is found. The mixed type is found along the

demarcation line of these two types, for example, at Baker

Lake; that is, during some months the Thule type prevails,

whereas in other months the Auroral Belt type prevails. Another mixed type occurs at the southern limits of the Auroral

Belt type, around 60 geomagnetic latitude. The geographic

extent of each type is shown on a polar map. The strong cor- relation of Es and magnetic activity point to a direct or indirect influence of corpuscular radiation on the occurrence of Es

in the polar region.

A-934 Pennsylvania. State College. Ionosphere Research Laboratory,

Survey of the literature of the ionosphere pertaining to long

waves. Contract AF 19(122)-44, Basic Ionospheric Research,

Technical Report, No. 23, July 10, 1951. 268 p. DWB-This

bibliography is comprised of abstracts and references to the

literature of the ionosphere and a portion of the upper atmos-
277

phere. Attention has been largely confined to the published

work concerning long waves and the levels in height where the

upper atmospheric physical characteristics affect the passage

of such waves. While, as mentioned above, the emphasis has

been placed on long wave and associated literature, many sur- vey papers and some of historical interest are included. Similarly, relevant work in physics and mathematics are considered.

--From author's abstract.

A-935 Pennsylvania. State College. Ionosphere Research Lab.,

Basic ionospheric research. Contract AF 19(122) -44, Quarterly Report, Nos. 2-10, June 16/Sept. 8, 1949 to May 24/Aut.

24, 1951. 9 pieces, figs. , refs. DWB--The quarterly reports

No. 2-10 deal with the work and progress on: 1A, Procurement and interpretation of 150 kc/s equivalent height versus

time recording; 2 A, Procurement and interpretation of 150

kc/s vertical incidence ionospheric absorption data; 3 A,

Equipment development for oblique incidence measurements

in the frequency range from 100 kc/s to 500 kc/s; 5 A, Long

wave literature survey abstracting and bibliography; 6 A, Long

wave theoretical development; 7 A, Long wave exploratory

work; 8B, h" - f recordings; 9B, WWV field strength recordings; 12 B, Theoretical development based on the double parabola theory; 13 B, Short wave exploratory work; 16 A, Oblique

incidence measurement at 150 kc/s; 18 A, Long wave ionospheric absorption; 19 A, Long wave equipment development;

21 A, 150 kc/s sky-wave polarization; 23 B, Oblique incidence

P'-f experiment; 24 B, E layer characteristics under quiet and

disturbed conditions; 28 A, Lunar tide study. Reprints of

papers by the project personnel are included in some of re- ports. Conferences, visits, papers published and reports issued in the course of the periods are listed. Rosters of personnel are included. --W. N.

A-936 Perlman, S. ; Kelley, L. C; Russell, W. J. and Stuart, W. D.,

Concerning optimum frequencies for space vehicle communication. Institute of Radio Engineers, Transactions, CS-7, No.

3:167-173, Sept. 1959. 9 figs. , 11 refs. DLC--A condensed

portion of the U. S. Army Signal Radio Propagation Agency's

'Tentative evaluation of the transmission factors for space

vehicle communication. " The factors related to communication

between space vehicles and earth stations are examined including noise temperature rather than noise figure, since the former

is the better basis for evaluation. --W. N.

A-937 Peterson, Allen M. (Stanford Univ. ), The interpretation of

long scatter echo patterns. U. S. Air Force. Cambridge Research Laboratories, Geophysical Research Papers, No. 7:

58-71, Dec. 1950. 8 figs. , 7 refs. , 11 eqs. DWB--
278

The theory of echo delay and of focusing effects is given. Experimental observations are compared with theory* —A. A.

A-938 Peterson, Allen M. , The mechanism of F-layer propagated

back-scatter echoes. Journal of Geophysical Research, 56(2):

221-237, June 1951. 8 figs. , 10 refs. , 15 eqs. MH-BH--Observed back scatter from the F layer (2 F) is difficult to explain

on the basis of its origin in the £ layer, but agrees with theory

if it is assumed that the scattering occurs at the earth's surface. This type of scattering is not unusual or sporadic but

occurs nearly 100% of the time. The leading edge of the pattern is sharply defined. The time delay as a function of frequency and transmitter power or pulse width is investigated

and the results shown graphically and explained. —M. R.

A-939 Peterson, A. M. ; Villard, O. G., Jr. ; Leadabrand, R. L. and

Gallagher, P. B. , Regularly observable aspect-sensitive radio

reflections from ionization aligned with the earth's magnetic

field and located within the ionospheric layers at middle latitudes. Journal of Geophysical Research, 60(4):497-512, Dec.

1955. --The phenomenon discussed was observed regularly in

the 6-30 Mc frequency range at the geomagnetic latitudes

43. 75 and at 55 . The echoes and the reflection geometry/

etc. suggest that the phenomenon is caused by the general

type of particle bombardment assumed to cause aurora. —W. N.

A-940 Peterson, A. M. et al. (all, Stanford Research Inst. , Menlo

Park, Calif. ), Radio and radar tracking of the Russian earth

satellite. Institute of Radio Engineers, N. Y. , Proceedings,

45(11): 1553-1555, Nov. 1957. 5 figs. , table. DLC-Brief ac- count of techniques employed and results obtained at the Stanford Research Institute. Experimental measurements with hastily assembled equipment — now improved — appear to yield

valuable scientific data on the upper atmosphere. --W. N.

A-941 Peterson, Allen M. (Stanford U. , Res. Inst. , Stanford, Calif.),

Optical, electromagnetic, and satellite observations of highaltitude nuclear detonations. Pt. 2. Journal of Geophysical

Research, Wash., D. C. , 64(8): 933-938, Aug. 1959. 5 figs.,

table, 10 refs. 'These remarks, and other papers at symposium

to be published in Aug. 1959 issue of Proceedings of the National Academy of Sciences. "

A-942 Peterson, Allen M.; Egan, R. D. and Pratt, D. S. , The IGY

three -freguency backscatter sounder. Institute of Radio Engineers, N. Y., Proceedings, 47(2): 300-314, Feb. 1959. 16 figs,

(incl. photos), 13 refs.
279

A-943 Pfister, W. , Effect of the D-ionospheric layer on very low

frequency radio waves. Journal of Geophysical Research,

54(4): 315-337, Dec. 1949. 14 figs. , 16 refs. , 12 eqs. Summary p. 315. MH-BH--The D layer is defined as a layer below

E layer, at about 60 km, affecting propagation of long waves.

Its probable electron and ion distribution is discussed, ion

production is about 10/cnrVsec. Reflection and transmission

coefficients are calculated. --C. E. P. B.

A-944 Pfister, Wolfgang (Geo. Res. Dir. Cambridge Field Sta. ), Effect of the D-ionospheric layer on very low frequency radio

waves. U. S. Air Force Cambridge Research Laboratories,

Geophysical Research Papers, No. 7:107-135, Dec. 1950. 15

figs. , 16 refs. , 12 eqs. DWB--The normal D layer exists at a level of about 60 km. The rate of ion production is of the

order of 10 cm"3 sec"l. Values for the reflection have been

calculated for different ionization and for different angles of

incidence. Also transmission values have been obtained. Instructive diagrams are given. The final assumed model of the

D layer is summarized. --A. A.

A-945 Pfister, Wolfgang, Magneto-ionic multiple splitting determined with the method of phase integration. Journal of Geophysical Research, 58(l):29-40, March 1953. 9 figs. , 6 refs.

DWB—The method used is a first-order W. K. B. approximation

with an integration path in the complex height plane. The re- fractive index versus height is represented on a Riemann sur- face with four sheets corresponding to upgoing and downcoming waves and ordinary and extraordinary types of polarization.

The branch points connecting the sheets are characterized as

reflection points or as coupling points. Suitable paths of integration in the Riemann surface determine the reflection coefficient for the various magneto-ionic components. Five possible fundamental components have been found, and an infinite number of additional components due mainly to multiple

reflections between the different reflection points. Numerical

computations have been carried out for one ionospheric model

with a Chapman distribution of electrons and an exponential

decrease of collision frequency located in a moderate magnetic

latitude. The results are represented in a sweep frequency picture of virtual height and absorption for five fundamental modes

of propagation. --Author's abstract.

A-946 Pfister, Wolfgang (Ionospheric Physics Lab. , Geophysics Res.

Directorate, A. F. Cambridge Res. Center), Study of fine

structure and irregularities of the ionosphere with rockets and

satellites. (In: Van Allen, James A. (ed. ), Scientific uses of

earth satellites. Ann Arbor, Univ. of Michigan Press, 1956.

p. 283-291. 2 figs.) DWB, DLC--
230

Almost all experiments using the ionosphere as a propagation

medium reveal the presence of irregular or blobby structure in

the electron distribution, and, consequently, a variety of

methods is in use to determine something about the blobby

structure, either by propagation through the ionosphere as in

the radioastronomic technique or by reflection within the layers. Only limited information is available from rocket experiments, but due to the fact that a rocket or satellite travels in

the midst of the ionosphere, experiments using transmissions

between the vehicle and the ground will be able to add a new

and very valuable type of information. Up to now, the contribution of the irregularities has been looked at more as a nasty

by-product which must be smoothed out in the data analysis.

However, from the data available, an analysis in terms of irregular structure appears to be quite promising. Based on ex- perience with known techniques, a set of experiments for a

satellite is being proposed. It is a combination of the pulsedelay experiment similar to the Air Force electron-density

rocket experiment with a kind of drift -type experiment measuring the signal amplitude fluctuations at three closely spaced

receivers. The real advantage of the fine -structure experiment

with satellites or rockets will be that the changing aspect allows us to gain a three-dimensional picture of the configuration of the blob, while so far we are used to looking only at

the two-dimensional diffraction pattern at the ground. --Author's abstract.

A-947 Pfister, W. and Keneshea, T. J. , Ionospheric effects on positioning of vehicles at high altitudes. U. S. Air Force. Cambridge Research Center. Air Force Surveys in Geophysics,

No. 83, March 1956. 27 p. numerous figs., table, 7 refs.

,

numerous eqs. DWB, DLC--When a radio wave penetrates the

ionospheric region, the presence of free electrons there causes it to deviate from its straight line path. The predictable

part of this effect has been computed in terms of error in the

initial angle of propagation and the error in the range of points

in the ionized region. The results are contained in a series of

graphs. The maximum error for a frequency of 1000 Mc/s is of

the order of 0. 1 mil and 45 meters respectively; these values

being inversely proportional to the frequency. The unpredictable part of the effects of the ionosphere is randomly varying

and unknown in its details, especially the dependence on frequency. From known facts of the ionospheric irregularities

and from theoretical considerations a justifiable estimate of

the effects can be obtained. This estimate is based on the

angular spread and other quantities derived from ionospheric

drift measurements and on an experimentally confirmed frequency dependence law. --Authors' abstract.
281

A-948 Piister, Wolfgang; Keneshea, T. J. et al. , The ionosphere. (In: Handbook of Geophysics for Air Force designers, ed. by

C. F. Campen, Jr., et al. 1st ed. Wash., D. C, 1957.

Ch. 15 (29 p. ) 64 figs. , table, 7 refs. , 4 eqs. ) DWB--A condensed review of the available data on ionospheric ionization, auroras and airglow as related to radio propagation, with ex- tensive graphical (charts, maps, records, diagrams) illustrative material on the E, F2, Sporadic E and auroral distributions

in space and time and their interrelationship and relationships

with sunspot activity, magnetic activity, altitude, critical frequency, etc. Recently compiled world-wide charts are presented for many of these elements. --M. R.

A-949 Pfister, W. (U. S. A. F. , Cambridge, Res. Center, Bedford,

Mass. ), Measurement of ionospheric fine structure by high

altitude rockets. AGARDograph, Paris, No. 34:183-192, Sept.

1958. 5 figs. , 2 refs. DWB (629. 1323 N864a)--In the United

States, two methods are being used for the determination of

electron density distribution from rocket experiments: the pulse

delay method and the phase delay method. The results derived

from both of these methods is different in one respect. The

stratifications appear considerably more pronounced in the

pulse delay method. The indications are that a basic difference exists in the way both methods respond to the existence

of horizontal irregularities in the ionosphere. In the pulse delay experiment two features have been included which permit

an estimate of the structure size of the irregularities. It is a variation of the frequency in seven steps between 4 and 5 Mc/s

and it is the reception of the signal with three closely-spaced

antennas. A preliminary analysis of some of the rocket data

gave 1.8 km and 0. 3 km respectively for the structure size.

The predominant feature of the results from pulse delay experiments is a pronounced stratification of the electron density as representing mean electron density with preferred levels at

94, 100, 106, 112, 118 and 128 km. The results cannot be

interpreted as representing mean electron densities for the

height levels concerned. However, the apparent stratification

is thought to be produced by an alignment of blobs of ionization at those preferred levels. --Author's abstract.

A-950 Phelps, A. V. and Pack, J. L. (both, Westinghouse Res. Lab.

Pittsburgh, Pa. ), Electron collision frequencies in nitrogen

and in the lower ionosphere. Physical Review Letters, N. Y. , 3(7):340-342, Oct. 1, 1959. 3 figs. , 10 refs. , eqs. DLC.

A-951 Phillips, G. J. , An apparatus for recording time-delays between radio fading characteristics. Journal of Atmospheric

and Terrestrial Physics, 6(2/3): 124-128, March 1955. 4 figs.,

ref. DWB-
282

When amplitudes from two aerials pass in succession through

minimum values a condenser is given a charge proportional to

the time between occurrences of the 2 minima. It is discharged through a center-pen recorder, polarity depending on the

sense of the time delay and length of spike on the interval.

Circuits are shown and practical details noted. --C. E. P. B.

A-952 Physical Society of London, Physics of the ionosphere: report

of the Physical Society Conference on the physics of the ionosphere, held at Cavendish Laboratory, Cambridge. Sept. 1954.

London, Physical Society, 1955. 406 p. numerous figs . , tables, refs. , eqs. DWB--For long review by James Paton see

Royal Meteorological Society, Quarterly Journal, 81:645, Oct.

1955. DWB--The results of the conference on the physics of

the ionosphere held Sept. 6 to 9 in Cambridge are published

in a sizeable volume. The 50 articles are grouped under the

following main headings: 1) the lowest ionosphere, p. 1-87;

2) irregularities and movements in the ionosphere, p. 88-211;

3) the F2 layer, p. 212-275; and 4) the mathematics of wave

propagation through the ionosphere, p. 276-406. Ionospheric

physicists from many countries contributed. The first paper in

each section comprises a review and bibliography of works in

the field. Nearly every aspect of ionospheric research or application is covered in an orderly manner by the variety of articles and the excellent grouping. This compendium, therefore,

represents a survey of progress in ionospheric physics up to

1954. »M. R.

A-953 Piddington, J. H. , The modes of formation of the ionospheric

layers. Journal of Geophysical Research, 56(3) :409, Sept.

1951. --Critically examines the eclipse data on recombination

coefficients in the E- and F-layers. Concludes that the coefficient in the E layer may be somewhat higher than the value

of 10-8 commonly assumed, and that no simple analysis of F

layer data can be considered to give a reliable value of the

coefficient. If the recombination coefficient is large, an additional source of ionization is required; suggests electric

current flow in the regions concerned as the most likely source.

Discusses solar regions responsible for ionization production.

Then considers possible ionization processes and wavelengths

for the F, E, and D layers. No new experimental data is described. —L. A. M.

A-954 Piddington, J. H. , The four possible waves in a magnetoionic medium. Philosophical magazine, London, 7 Ser. , 46

(381): 1037-1050, Oct. 1955. 2 figs. , 14 refs. , 16 eqs. DWB.

Also: The four possible waves in ionized gas in a magnetic

field. Nature, London, 176(4488) :875-876, Nov. 5, 1955.

fig. , 10 refs. DWB--
283

Discussion of the properties of radio waves propagated

through gas permeated by a magnetic field. Besides the or- dinary and extraordinary waves (identical with radio and E

waves) there is a 'magnetic -sound' wave at low frequencies

and an analogous wave at high frequencies termed the 'magnetic-plasma' wave, which may be important in the origin of

intense non-thermal solar radio emission. The relation between these four waves is studied. 'The magneto-ionic medium is quadruply refracting, transmitting 4 different waves".

--C. E. P. B.

A-955 Pierce, J. A. , Pulse transmission over long distances . U. S.

Air Force. Cambridge Research Center, Geophysical Research

Papers, No. 7:56-57, Dec. 1950. DWB--The author used a stable oscillator with manual adjustment of frequency and

phase and also either a stable or relatively unstable oscillator with a servo-mechanism. A few results are discussed,

showing the variation in behavior and the general importance

in communication of the Pedersen rays, --A. A.

A-956 Pierce, J. R. and Kompfner, R. , Transoceanic communication by means of satellites. Institute of radio Engineers,

Proceedings, 47(3): 372-380, March 1959. 3 figs. , 5 tables,

6 refs.

A-957 Piggott, W. R. , The abnormalities in the ionosphere at high

latitudes. Nature, London, 171( ):124, 1953. -Study of the

variations, with respect to time and location, of the frequency

of occurrence of storm types E and D shows that the polar re- gions may be divided into three zones, the polar zone, the

storm belt and the polar quiet zone. Within the storm belt,

the most dense forms of storm E ionization are practically confined to an area centered near Canada, while the existence

can be demonstrated of two centers of activity in the D region,

spaced 180 apart, which rotate once around the earth every

48 hours.

A-958 Piggott, W. R. , The reflection and absorption of radio waves

in the ionosphere. Institution of Electrical Engineers, Proceedings, Pt. 3, 100( ):61-72, March 1953. -A brief historical re- view is given of the investigations on the absorption of radio

waves made in the United Kingdom since 1935 together with a detailed discussion of the factors which must be considered

when making accurate measurements of this phenomenon. An

outline of the theory of ionospheric absorption and its application to practical absorption measurements is included. The effects of double refraction, polarization, spatial attenuation

dispersion, ionospheric inhomogeneities and partial reflection,

which modify the apparent attenuation of radio waves reflected
284

in the ionosphere, are discussed. The methods used to minimize errors due to these factors are presented in detail. The

experimental techniques used in the routine absorption measurements are described fully. The detailed results of the

measurements of the absorption of radio waves in the ionosphere, are included.

A-959 Piggott, W. R. , D. S. I. R. ionospheric absorption measuring

equipment. Wireless Engineer, London, 32(6): 164-169, June

1955. 4 figs. , 4 refs. DLC—The principles of ionospheric

absorption apparatus, first designed by Sir E. Appleton in

1935, are described with wiring diagrams. It employs a very

stable linear r-f pulse. —C. E. P. B.

A-960 Piggott, W. R., On the variation of ionospheric absorption

at different stations. Journal of Atmospheric and Terrestrial

Physics, 7(4/5): 244-246, Oct. 1955. 6 refs. DWB--Correlation of day-to-day variations of absorption at 2 Mc/s at Swansea and Slough is about 0. 92 both in winter and summer. Freiburg-Slough correlation is not directly possible, probably owing to discrepancies in deducing the absorption. "After allowing for known sources of error, it is considered that the residual differences in summer are too small to be significant, but

it is probable that real differences occur in winter. "--C.E. P. B.

A-961 Piggott, W. R. ; Beynon, W. J. G. ; Brown, G. M. and Little,

C. G. (comps. ), Measurement of ionospheric absorption. International Geophysical Year, 1957/1958, Annals, 3(IGY Instruction Manual): 173-226, 1957. figs., tables, refs., eqs.

Contents: General theory of ionospheric absorption, p. 177-

178. Piggott, W. R. ; Beynon, W. J.G. and Brown, G. M.

The pulse reflection method of measuring ionospheric absorption, p. 179-203. Ionospheric absorption and f-min. p. 204-

206. Little, C. G. : The measurement of ionospheric absorp- tion using extra-terrestrial radio waves, p. 207-217. Brief

report on some absorption intercomparison experiments, p. 218-

226. DWB—A systematic and thorough treatment of theory and

practice in measurement of ionospheric absorption in general

and for IGY in particular. The methods involve study of variations in amplitudes of signals, in minimum frequency of echoes

from the ionosphere and variations in amplitudes of signals

from outside the atmosphere. During IGY the geographical variations, solar relations, winter anomalies, corpuscular effects,

etc. will be studied. Appendices give symbols, abbreviations

and terminology used in absorption measurements, and detailed

program for pulse reflection absorption measurements during

IGY (frequencies, sampling, noon and night observations, diurnal variations, measurement of constant solar zenith angle and

high latitude measurements). --M. R.
285

A-962 Piggott, W. R. (DSIR Radio Research Station, Slough), The

gyro-frequency in the E layer above Slough. England. Journal

of Atmospheric and Terrestrial Physics, N. Y. , 16(1/2):197-

198, Oct. 1959. 6 refs. , 2 eqs. DWB, DLC --Measurements

of the gyro-frequency, fH# *n tne E layer from the separation

of f E and fxE at Slough give fn = 1. 236 + 0. 015 Mc/s. The

calculated value is fjj = 1- 2? Mc/s. The difference is consistent with that found by Scott using f E — f zE measured at

high latitudes. --Author's abstract.

A-963 Piggott, W. R. and Bhattacharyya, J. , On the mode of propagation in the E layer. Journal of Atmospheric and Terrestrial

Physics, N. Y. , 17(1/2) -.150-157, Dec. 1959. fig., 2 tables,

17 refs. , 2 eqs. DWB, DLC--Lepechinsky and Durant's suggestion — that f E is incorrectly interpreted at stations where

the dip exceeds about 60° — is critically tested using observed fQ E data. All the tests agree in showing that this hypothesis is wrong, the critical frequency being reduced correctly

for stations with dips up to 89 . The common type of Es trace

extending approximately tn/2 above f E interpreted by Lepechinsky as a magneto-ionic effect above fzE, is shown to be due

to sporadic E and not magneto-ionic effect. It follows that the

collisional frequency near the maximum of the E layer is of the

order 10^ sec-1 and not 10® sec-1 as required by Lepechinsky.

--Authors' abstract.

A-964 Piggott, W. R. , A rapid method of obtaining accurate virtual

heights from an ionogram. Journal of Atmospheric and Terrestrial Physics, 14(1 -2): 175-177, April 1959. 2 figs. , ref.

A-965 Piggott, W. R. , The calculation of the median sky wave field

strength in tropical regions. Dept. of Scientific and Industrial

Research. Her Majesty's Stationery Service, London. Radio

Research Spec. Report, No. 27, 1959. 38 p. 28 figs. , 3

tables, 13 refs.

A-966 Pikel'ner, S. B. (Crimean Astrophysical Obs. ) and Lehnert, B.

(Royal Inst, of Tech. , Stockholm), (Comments on Lehnert 's)

Magneto-hydrodynamic waves in the ionosphere and their application to giant pulsations. Tellus, Stockholm, 9(1): 138-

139, Feb. 1957. eqs. DLC-PIKEL'NER, in a criticism of

LEHNERT's paper on magneto hydrodynamic waves in the ionosphere attempts to show that the coupling between the ions

of a neutral gas is too poor for the total mass of the gas to oscillate as a whole in the normal E, F, and F2 layers. LEHNERT, in his reply, states that this is true outside the auroral

zone, but that inside the auroral zone the periods of oscillation of ordinary hydromagnetic waves are consistent with the

giant pulsations of 60 to 300 sec if the ionization is high within this region of the giant pulsation. More data are needed. -- M. R.
286

A-967 Pineo, V. C. (M.I. T., Lincoln Lab. , Lexington, Mass.),

Off -path propagation at VHF. Institute of Radio Engineers,

Proceedings, 46(5^ Pt. 1:922, May 1958. 2 figs. , 4 refs.

DLC--A propagation experiment involving simultaneous measurement at Sterling, Va. and two off-path stations of signals

beamed from Cedar Rapids, Iowa toward Sterling, is described

and found to indicate that ionospheric scatter propagation consists of two modes, one due to solar influence, the other to

meteoric ionization. —G. T.

A-968 Pitteway, M. L. V., Reflexion levels coupling regions in a horizontally stratified ionosphere. Royal Society of London,

Philosophical Transactions, Ser. A, 252(1004): 53-68, Oct.

1959. 12 figs. , 12 refs.

// A-969 Plendl, Hans, Uber Ziele und Ergebnisse mehriahriger Ionos - pharenforschung. (The aim and results of long period ionospheric research. ) Deutsche Akademie der Luftfahrtforschung,

Munich, Schriften, No. 6:29-91, 1938/1939, pub. 1939. 34 +

13 figs. , (incl. photos). Discussion, p. 68-91. DLC--Continuous ionospheric records, made at Munich, Potsdam and

Rechlin with 80 m impulse equipment, during 13 solar rotations from Dec. 1937 to Dec. 1938, are presented, analyzed

and discussed separately. The period was one of most ex- treme sunspot and auroral-magnetic storm activity. Records

show that ionospheric structure is more variable than tropospheric weather. The need for records over a period of 50

years or more, in order to establish diurnal seasonal and solarperiod variations in the different layers and time and intensity

relations for irregular as well as regular phenomena, is emphasized in discussion. Reflections from auroral forms show

on a number of the records. It was found that disturbances in

the geomagnetic field begin a few hours before ionospheric disturbances — an important point for forecasting disturbances in

radio propagation. It was also found that vertical reflections

approximate conditions for long distance propagation, which

gives a convenient method of sounding for radio-ionospheric

forecasts. This does not apply to the abnormal E layer which

is of local character. The detailed discussion by BARTELS,

GOUBAU, ZENNECK, MOGEL, DIEMINGER, LANGE and O. V.

SCHMIDT give additional illustrations of ionospheric records

and comments on recent discoveries. The last comment, by

Schmidt (p. 79-91), shows by means of models and excellent

photographs the results of seismic wave propagation experiments in various media and at boundaries of media of different

density, with theory of analogy to ionospheric propagation

developed in some detail. —M. R.
287

A-970 Poeverlein, Hermann, Strahlweqe von Radiowellen in der

Ionosphare. (Radiation paths of radio waves in the ionosphere. ) Bayerisohen Akademie der Wissenschaften, Sitzungsberichte, 1948. Also Ibid., Zeitsohrift fur angewandte Physik,

l(10):517-525, Oct. 1949. Also Ibid. , 2(4):152-160, 1950.

A-971 Poeverlein, H. , Ionosph&ren-Grenzfreauenz bei echiefem Einfall . (Ionosphere critical frequency at oblique incidence.

)

Zeitschrift fur angewandte Physik, 5(1):15-19, 1953. 4 figs.

,

25 refs. , 12 eqs. DLC--A method of constructing paths of

radio waves in the ionosphere which takes account of the

earth's magnetic field is applied to calculate the critical frequency for any angle of incidence. Graphs show for waves of

3. 75 MHz the ratios of critical frequency for vertical incidence to incidence at any angle, ratio for waves in E-W plane to

those in magnetic meridian, and effect of wave length (7. 5-0.

75 MHz). -C.E.P.B.

A-972 Poeverlein, Hermann (U. S. Air Res. & Dev. Comm. , Bedford,

Mass. ), Low-frequency reflection in the ionosphere. Pt. 1 . Journal of Atmospheric and Terrestrial Physics, London, 12-

(2/3): 126-139, 1958. 14 refs. , 44 eqs. DLC--A theory of low

frequency reflection in the ionosphere is developed. At wavelengths long compared to the layer thickness, the ionospheric

layer is considered as a thin, conductive sheet, that leads to a discontinuity of the electromagnetic field. A thicker layer

is subdivided into many thin (or differential) sublayers. The

field is then thought of as a superposition of many partial

waves, each of which is reflected by an individual sublayer.

An additional penetrating wave must be assumed. At the lowest frequencies — that is, in the case of thin-sheet reflection — the currents in the layer are horizontal and the reflection is

of the metallic type, always showing reversal of the horizontal

E-component. Dielectric -type reflection with sign or phase

transition at the Brewster angle is obtained at somewhat higher

frequencies, if vertical and horizontal current density components are of comparable magnitude. The present first part of

the paper deals with the thin-sheet reflection theory and the

fundamentals of the general theory. Specialized cases of the

general theory and some consequences will be discussed in

the second part. The frequencies under consideration are roughly 1-100 kc/s. --Author's abstract.

A-973 Poeverlein, Hermann (A. F. Cambridge Research Center),

Low-frequency reflection in the ionosphere. Pt. 2 . Journal of

Atmospheric and Terrestrial Physics, N. Y. , 12(4): 236-247,

1958. fig. , 24 refs. , 9 eqs. DLC--The first part of the paper

dealt with a theory for ionospheric reflection of low frequencies, i. e. of wavelengths comparable to or great compared to
288

the layer thickness. In the present second part various ranges

of data are specified and their reflection characteristics are investigated. Metallic -type reflection is found at high electron

concentration and dielectric -type reflection at medium electron

concentration above a certain frequency limit. In this latter

case, the currents in the ionospheric layer have the direction

of the terrestrial magnetic field and the propagation in the layer is very peculiar. Some consequences of the theory are discussed with references to observations where possible. Among

them there are statements about phase, sign, and Brewster case

and possibilities of transmission through a layer. The final

section brings some remarks on the theory, mainly on the fieldstrength quantities introduced. These quantities allow an interpretation which points at a close relationship to Budden's

theory. --Author's abstract.

A-974 Poincelot, Paul, Reflexion d'une onde electromagnetigue plane

8ur un milieu ionise. (Reflection of a plane electromagnetic

wave from an ionized medium. ) Academie des Sciences, Paris,

Comptes Rendus, 241(2): 186-188, July 11, 1955. 2 refs. , 15

eqs. Also his: Reflexion d'une onde electromagnetigue plane

sur un gaz ionise suivant une certaine loi. (Reflection of a plane electromagnetic wave from an ionized gas according to a given law. ) Ibid. , 241(3) :290-292, July 18, 1955. 14 eqs.

Also his: Reflexion d'une onde electromagnetigue plane sur un

gas ionise. (Reflection of a plane electromagnetic wave from

an ionized gas. ) Ibid., 241(9): 649-651, Aug. 29, 1955. ref .

,

eqs. DLC --Reflection of plane electromagnetic waves is treated mathematically, considering pulse frequency and structure

of the reflecting ionized medium (electronic density, height,

etc.). The analysis involves Hankel functions and their asymptotic developments. --G. T.

A-975 Poincelot, Paul, Influence de 1 'absorption sur le coefficient

de reflexion de 1 'ionosphere. (Influence of absorption on the

reflective index of the ionosphere. ) Annales des Telecommunications, Paris, 14(3/4): 54-58, March/April 1959. 15 refs.

,

eqs. DLC —Study on the influence of the absorption by ionosphere on its reflective index under normal incidence. Author

investigates the propagation of a plane electromagnetic wave

through a stratified medium, admitting that the electronic concentration varies linearily with respect to altitude. Generalezing the hypotheses made in several former publications,

author introduces a viscous resistance and computes under

these conditions the reflective index of the considered ionosphere layer. The value of the reflective index is expressed

as follows: [/°] = e-4 /B w^/3 otc, where w = pulsation of the

wave; c = speed of light in the vacuum. /9 is determined by

means of the ratio $ - r/m (m being an electron, possessing
289

a speed v and subject, on the part of the medium, to a force

j = — r v); OC intervenes in the law of the index n fluctuation with respect to the height z above the basis of the ionospheric layer: n^ = 1 — 06 z/w^. The adopted hypotheses

correspond to reflection upon the lower layers of the ionosphere. Numerous experimental checkings have been made. -- A. V.

A-976 Polar Atmosphere Symposium, Oslo, July 2-8, 1956, Proceed- ings. Pt. 2, Ionospheric Section. Journal of Atmospheric and

Terrestrial Physics, London, Special Supplement, 1957, issued

1958. 212 p. figs. (incl. photos), tables, refs. , eqs. DLC

--Twenty-one papers on the polar ionosphere arranged according to the 3 sections of the symposia, each section with an

extensive discussion: I. Drifts in the ionosphere; II. Prognostic techniques of the ionosphere with special reference to Arctic regions; and III. Absorption. The opening speech by

FRANK L. WATTENDORF, director of AGARD of NATO gives

the history of the Advisory Group for Aeronautical Research

and Development - conceived by TH. VON KARMAN - and

of the symposium in Oslo on July 2-8, 1956, where polar-ionospheric and meteorological research would be discussed;

followed by an introduction speech by the late H. U. SVERDRUP, who mentions his early interest in Arctic research,

dating back to 1918 when he departed on the "Maud, " and on

the great changes in Arctic observation techniques since 1918-

25 and, finally, on the difference in emphasis between Arctic

and tropical meteorology — in one case radiation processes

and inversions are foremost; in the other, the convective processes and condensation are more prominent. --M, R.

A-977 Pope, Joseph H. , Diurnal variation in the occurrence of "Dawn

chorus". Nature, London, 180( ):433, Aug. 31, 1957. figs.

,

table, refs. DLC--Brief report on observations Jan. 1 -July 2,

1956 using equipment sensitive to 1 - 10 kc/s. Dawn chorus

was present in 224 of the 2, 784 one min hourly observing periods, diurnal variation of which are shown in a histogram,

featured graphically in local time occurrence as a function of

geomagnetic latitude and compared with other localities in a table given. --W. N.

A-978 Power, Thomas S (U. S. A. F. ), Air Force research and development in space technology. Aeronautical Engineering Review, N. Y. , 16(9):36-39, Sept. 1957. port. DLC--Since

airplanes (i. e. , the Bell X-2) have now flown as high as

126, 000 ft, they are effectively if not actually operating in

"space, " for 99% of the atmosphere lies below that level and

many of the problems encountered are the same as if there
290

were no atmosphere at all. Thus in any aviation system,

knowledge of the environment (the atmosphere) at high altitudes is of vital concern. Solar radiation, air masses, the

jet stream, ionosphere, cosmic rays, meteoric debris and

their effects on planes, on rockets and communications and

on each other are among the phenomena to be investigated intensively. Weather observation and forecasting, and human

(biological) factors are no less important. --M.R.

A-979 Prenatt, Raymond E. (Aberdeen Proving Ground, Md. ), Fara^

day rotation measurements at Fort Churchill . Journal of Geophysical Research, Wash., D. C, 64(9): 1340-1341, Sept.

1959. 2 figs. , eq. DLC.

A-980 Price, R. E. , Travelling disturbances in the ionosphere. Nature, London, 172(4368): 115-116, July 18, 1953. 2 figs.

,

2 refs. DWB—Observations at 3 points at Nedlands, Western

Australia, on 5. 8 Mc/s recorded motion of disturbances in

reflecting layer. Direction of motion 90-180°E of N in summer

and 0-60 E of N in winter with rapid change over at equinoxes.

Speed 5-20 km/min with maximum at 10. No correlation with

auroras or weather. «C. E. P. B.

A-981 Price, R. E. and Green, P. E. , Jr. , Measurement of ionospheric path-phase for oblique incidence. Nature, London,

179(4555):372-373, Feb. 16, 1957. 4 figs. , 4 refs. DWB--

Three techniques are described for direct measurement of

changes of path-phase, involving transmission of short radiofrequency pulses having a highly stable carrier frequency. -- C E. P. B.

A-982 Probst, S. E. and Krause, George E. , IBM 704 Program to

determine maximum usable frequency (MUF) and lowest usable

freguency (LUF) for HF propagation. U. S. Army Signal Radio

Propagation Agency, Ft. Monmouth, N. J. , Oct. 1959. Project 625.

A-983 Quinn, T. P. , Coherent detection system for a rocket-borne

ionospheric sounder. Pennsylvania. State Univ. Ionosphere

Research Lab. , Contract DA-35-061-ORD-577, Scientific Report, No. 113, Dec. 15, 1956. 63 p. 20 figs., 9 refs., eqs.

DWB (M10. 536 P415i)--An experiment proposed by the Ionosphere Research Laboratory is discussed. The experiment is

designed to measure electron densities in the ionosphere by

means of rocket-borne instruments. The preliminary design

for two rocket-borne coherent detection systems is presented.

The detection system for a daytime experiment is capable of

detecting an ionosphere probe signal when the signal to noise

ratio is much less than unity. --Author's abstract.
291

A-984 Rangarajan, S. (Kodaikanal Obs. , Kodaikanal, India), The

sporadic E layer at Kodaikanal. Journal of Geophysical Research, 59(2): 239-246, June 1954. 3 figs. , 2 tables, 9 refs.

MH-BH--An examination of the ionospheric records at Kodaikanal, which is located almost on the geomagnetic equator,

reveals that the sporadic E layer here has some regular features not observed at other latitudes. It occurs in nearly 93%

of the half-hourly records during the daytime. Two main types

of Es are observed; namely, (1) the patchy type with a wellmarked diurnal variation and (2) which occurs mostly during

afternoons. It is found that neither meteoric activity nor thunderstorm activity has any appreciable influence on the

formation of either of the two types of Es. No correlation is

observed between Es and the geomagnetic field. --Author's

abstract.

A-985 Rao, B. Ramachandra and Rao, E. Bhagiratha (Ionosphere

Lab. , Andhra Univ. , Waltair), A continuous radio wave meth- od of studying travelling; disturbances in the ionosphere.

Journal of Scientific and Industrial Research, New Delhi, Sec.

A, 13(10): 462-466, Oct. 1954. 2 figs. , 2 tables, 7 refs. DLC

--Different methods of determining ionospheric drift are re- viewed, and the new method, which involves measurement of

the time difference between passage of peculiar peaks on continuous ionospheric records, between one station and another

nearby station with nearly the same frequency, described in

detail and numerical examples cited and records presented by

way of illustration. The stations cited are Calcutta, and Dacca,

in 41 m band. Data for May and June 1953 show movements

ranging from 7 to 21 km/min, over a distance of 120 km. Reasons for assuming the drift to lie in the F rather than the E layer are given. Movements are usually toward the south (N-wind)

but one case shows opposite drift. --M. R.

A-986 Rao, B. Ramachandra and Murty, D. Satyanarayana (both,

Andhra Univ. , Waltair), jl simple method of studying winds

in the ionosphere by using continuous -wave radio . Nature,

London, 177(4522) -.1222-1223, June 30, 1956. fig. , 2 refs.

DWB--Transmissions from Madras on 31 m reflected once from

F2 region and received on 3 vertical aerials at Waltair were

recorded on the same roll of paper. A typical record shows a displacement of 40-90 m/s from 150-230 E of N. --C. E. P. B.

A-987 Rao, B. Ramachandra; Rao, M. Srirama and Murty, D. Santyanarayana (all, Ionosphere Lab. , Andhra Univ. , Waltair),

Investigation of winds in the ionosphere by spaced receiver

method. Journal of Scientific and Industrial Research, Sec. A,

New Delhi, 15(2):75-81, Feb. 1956. 4 figs., 13 refs. , 6 eqs.

DWB, DLC-
292

Details of equipment and results of soundings presented in

text and illustrations (recorder records), polar diagrams showing seasonal variation of wind movements in the E and F re- gion in winter from NE and summer (W in E layer, indefinite

in F); wiring diagrams, etc. based on spaced receiver observations (MITRA, 1949), made at the Ionospheric Laboratory at

Andhra Univ. , Waltair, India, in 1954 using 3 receiving antennas and one pulse sender operating in the 2-6 Mc/sec range

with a pulse width of 200 microseconds. --M. R.

A-988 Rao, B. Ramachandra and Rao E., Bhagiratha (both, Ionospheric Research Labs. , Andhra Univ. , Waltair, India), Horizontal ionospheric drifts in the F2 region at equatorial latitud- es. Nature, London, 181(4623): 1612-1613, June 7, 1958. fig. , table, 5 refs. DWB--This review discusses the various ionospheric F2 region drifts which had been studied in detail at a number of high-altitude stations. Reference is made to Briggs

and Spencer, Rep. Prog. Phys. 17, 245(1954); Martyn, D. F.

,

Physics of the Ionosphere, 163 (1955); Purslow, B. W. , Nature, 181, 35(1958); Mitra, S. N. , Proc. Inst. Elect. Eng.

,

Pt. 3, 96, 441 (1949); Rao, B. R. , Rao, N. S. , and Murty,

D. S., J. Sci. Indust. Res., 15A 75(1956). A detailed ac- count of the same investigation will be published in the near

future. --N. N.

A-989 Rao, B. Ramachandra and Murty, D. Satyanarayana (both.

Ionospheric Res. Lab., Andhra Univ. , Visakhapatnam), A

new continuous wave radio method for the study of ionospheric

drifts. Journal of Scientific and Industrial Research, New Delhi, Sec. A, 17(12), Special Supplement, Dec. 1958. p. 63-67.

2 figs. , 2 tables, 3 refs. DWB, DLC--A simplified method is

described involving transmission from a distant sender received

by three simple vertical aerials at the corners of a right angled

triangle, signal strength being recorded side by side on a photographic paper. Sectional view is given. Comparison with

other methods show that this method yields consistent reliable

results. Another advantage is that choice of proper frequencies enables drift measurements at different ionospheric locations

from the very same receiving center.

A-990 Rao, B. Ramachandra and Ramana, K. V. V. (both, Ionospheric Res. Lab. , Andhra Univ. , Visakhapatnam), Diurnal variation of ionospheric absorption on 5. 65 Mc/s at Waltair during

the IGY. Journal of Scientific and Industrial Research, New

Delhi, Sec. A, 17(12), Special Supplement, Dec. 1958. p. 56-

58. table, 9 refs. , 6 eqs. DWB, DLC--The equations used to

obtain the ionospheric absorption by calculating comparatively

the amplitude of the echo received with the amplitude if the ionosphere were a perfect reflector are given. Procedure and
293

equipment used during the period March - Aug. 1958 are described. Tabulated n values (cos x index) vary from 0. 88 to

1. 75, average 1. 25 as against the theoretical 1. 5. --W. N.

A-991 Rao, B. Ramachandra; Rao, E. Bhagiratha and Ramana Murthy,

B. V. (all, Ionospheric Res. Lab. Andhra Univ. , Waltair),

Effect of magnetic activity on drifts of the F2 region. Nature,

London, 183(4662): 667-668, March 7, 1959. fig., 4 refs.

DWB--Ionospheric drift observations made at Waltair (mag. lat.

9°30'N) over a period of 16 months during Feb. 1956 and May

1958, are analyzed. This preliminary report uses 466 observations in plotting a graph of the variations of the speed of

drifts of the F2 region with geomagnetic index and obtains a mean straight line which indicates that there is a decrease of

mean drift speed of the F2 region with increase of magnetic

activity in the range of 0-6. --N. N.

A-992 Rao, B. Ramachandra and Rao, E. Bhagiratha (both, Ionospheric Lab. Andhra Univ. , Waltair), Study of horizontal drifts

in the Fl and F2 regions of the ionosphere at Waltair (17 43' N,

83°18'E. mag, lat. 9°30'N). Journal of Atmospheric and Terrestrial Physics, London, 14(1/2): 94-106, April 1959. 5 figs.

,

4 tables, 11 refs. DLC—Results of the analysis of drift measurements made at Waltair for the Fl and F2 regions over a period of 2 years are presented in this paper. The main features

of the diurnal and seasonal variation of drifts in F2 region are given in detail. The general pattern of drift movements for

this low latitude station is found to be in phase opposition to

those observed at high latitudes, thus confirming F2 region

drift theory given by Martyn (1955). --Authors' abstract.

A-993 Rao, B. V. T. and Rao, M. K. , Ionospheric absorption over

Delhi. Institution of Telecommunication Engineers, Journal

(India), 4(4):205-208, Sept. 1958. 5 figs. , 5 refs.

A-994 Rao, M. Srirama and Rao, B. Ramachandra, Long-period fading in medium-wave radio signals. Nature, London, 176(4479):

459-460, Sept. 3, 1955. fig. , table, 8 refs. DWB--Fading of

transmissions on 1.42 Mc/s from Madras received at Waltair,

600 km distant, in May 1954 showed a period of 7 min, decreasing with time (7 h to 8 h). This agrees with calculations based

on magneto-ionic theory. --C. E. P. B.

A-995 Rao, M. Srirama and Rao, B. Ramachandra, Analysis of fading records from four spaced receivers for ionospheric wind

measurements . Journal of Atmospheric and Terrestrial Physics,

10(5/6): 307-317, 1957. 4 figs. , 4 tables, 6 refs. , 3 eqs.

DWB--This paper deals with the analysis of fading records from

four spaced receivers of pulsed radio waves reflected at vertical
294

incidence from the ionosphere, with a view to finding out the

shape of lines of maxima and evolve a better method of calculating wind data. The usual three-station method of measurement of ionospheric winds using average displacements is

found to give inaccurate results. It is shown that the method

of calculating wind data using median values of displacements

gives reliable results. A new and improved method of analyzing wind records for evaluation of true velocities and direction

is also presented. --Authors' abstract.

A-996 Rao, M. N. and Mitra, A. P. (Radio Propagation Unit, New

Delhi), Effect of vertical drifts on the nocturnal ionization of

the lower ionosphere. Journal of Atmospheric and Terrestrial

Physics, London, 13(3/4) :271 -290, Feb. 1959. 14 figs. , 2

tables, 18 refs. , 12 eqs. DLC --Effect of vertical ionic drift

velocities on the night-time ionization density in the lower

ionosphere for heights ranging between 80 km to 130 km is

studied by a method of successive approximation. Values are also given of the effective recombination coefficient as a function of height and time for these drift velocities. Velocities

ranging from 1 to 20 km/hr are used. The resultant ionization

profiles for velocities 1-5 km/hr represent magnetically quiet

conditions, while those for higher velocities would represent

disturbed conditions of increasing severity. It will be noted

that the ionization density decreases for upward drift and increases for downward drift. The present work provides a quantitative explanation of the sudden cessation of night-time echoes of low-frequency radio waves at times of magnetic disturbances, such as those observed at the Pennsylvania State University (Lindquist, 1953). --Authors' abstract.

A-997 Rao, M. Srirama and Rao, B. Ramachandra (both. Ionospheric

Res. Lab. Physics, Dept. Andhra Univ. ), Investigation of

magnetic -ionic fading in oblique incidence medium-wave trans - missions. Journal of Atmospheric and Terrestrial Physics, N. Y.,

12(4) -.293-305, 1958. 4 figs. , 6 tables, 8 refs. , 13 eqs. -- Periodic fading of magneto-ionic origin observed in oblique incidence medium wave records is interpreted theoretically by

calculating the phase paths by a graphical integration method

assuming Chapman and parabolic ion distribution. Analytical

expressions have also been derived for phase paths of both

magneto-ionic components by an approximate method involving

the use of an empirical formula for q-x curves. The theoretical

values of fading periods compared very well with the experimental data, the agreement being particularly good for the case

of Chapman distribution. --Authors' abstract.
295

A-998 Rastogi, R. G. (Nat'l. Res. Council, Ottawa, Canada), The

diurnal development of the anomalous equatorial belt in the F2

region of the ionosphere. Journal of Geophysical Research,

Wash. , D. C. , 64(7): 727-732, July 1959. 4 figs. , 26 refs.

DLC—The latitudinal variation in the critical frequency of the

F2 layer was studied for each hour of the day during the equinoctial months of a year at sunspot minimum. The middle latitude maxima first develop at low latitude and shift poleward

with the progress of the day, the course being reversed in the

evening hours. The double maxima in the diurnal variation of

foF2 are less separated with increasing latitude and finally

converge to a single maximum at a dip of about 25 . These

two anomalies in foF2 are suggested as being due to the vertical drift of ionization, together with its motion towards the

poles in the morning and towards the equator in the afternoon.

Other anomalies of F2 can be also explained by a meridional

transport of ionization. --Author's abstract.

A-999 Rastogi, R. G. (Nat'l. Res. Coun. Postdoctorate Fellow),

Magnetic control on the variations of the critical frequency of

the F2 layer of the ionosphere. Canadian Journal of Physics,

Ottawa, 37(7): 874-879, July 1959. 3 figs. , 16 refs. DWB,

DLC--The paper discusses the comparative influence of the

true magnetic and smooth geomagnetic latitudes on the diurnal

and latitudinal variations of the critical frequency of the F2

layer (foF2) at low latitudes. The diurnal variations of foF2

are shown to differ considerably at stations having the same

geomagnetic latitude, but the discrepancies disappear when

the true magnetic latitude is taken into consideration. The

latitudinal variation of noon values of foF2 is also shown to

present discrepancies for low latitude stations in the geomagnetic latitudes plot, but on true magnetic latitude plots the

points fall regularly along a smooth curve. --Author's abstract.

A-1000 Ratcliffe, J. A. , Diffraction from the ionosphere and the fad - ing of radio waves. Nature, London, 162(-4io5):9-ll. —A theory

of fading is outlined which regards a "single" reflected wave

as the sum of contributions from a large number of scattering

centers in the reflecting region, moving with velocities distributed according to a Gaussian law. The resultant signal is

found to be analogous to that produced when random noise is

passed through a filter with a specified band-pass characteristic and the results of an analysis of this case are applied to

the present problem. It is shown that the observed fading

characteristics of radio waves on various frequencies from 4

Mc to 16 kc are in accord with the theory, the rms values of

the scattering center velocity being of the same order of magnitude in each case. The theory accounts for the observed

fact that the rate of fading is roughly proportional to the
296

frequency of the wave and the distance of the transmitter.

A-1001 Ratcliffe, J. A. (Cavendish Lab. , Cambridge, Univ. ), A re- view of the research work being conducted at the Pennsylvania

State College on the propagation of radio waves through the

ionosphere. Pennsylvania. State College. Radio Propagation

Laboratory. Contract AF 19(122) -44, Technical Report, No. 4,

July 15, 1949. 7 p. DWB.

A-1002 Ratcliffe, J. A. , The production of fading by an irregular

ionosphere. U. S. Air Force Cambridge Research Center,

Geophysical Research Papers, No. 7:166, Dec. 1950. DWB--

Short abstract of a report on the conference of June 1949. Radio fading is produced by diffractive reflection from the ionosphere acting as a rough surface. --A. A.

A-1003 Ratcliffe, J. A. (Cambridge, Eng. , Cavendish Lab. ), The

propagation of long and very-long waves. U. S. Air Force

Cambridge Research Laboratories, Geophysical Research Papers, No. 7:17, Dec. 1950. DWB--A short abstract of the paper presented on the Conference on Ionospheric Research in

June 1949. The daytime downcoming wave on 16 kpc is strong

(summer reflection coefficient r = 0. 15) but on 100 kpc it is

weak (r = 0. 01). «A. A.

A-1004 Ratcliffe, J. A. , The analysis of fading records from spaced

receivers . Journal of Atmospheric and Terrestrial Physics,

5(3):173-181, July 1954. 8 figs. , 8 refs. , 10 eqs. Also:

Newstead, Gordon, The determination of the velocity of winds

from spaced fading experiments. Ibid., 182-185. fig., 3refs.,

7 eqs. DWB--RATCLIFFE analyzes a record of travel of pulses,

reflected at vertical incidence, along two arms of a rightangled

triangle. The record shows considerable variability, the cause

of which is discussed. It is shown that some but not all re- cords of this type could be explained in terms of a constant

wind and isotropically random amplitude pattern. NEWSTEAD

further analyzes records of fading at 3 points and shows that

under certain conditions it should be possible to deduce statistics of wind variation. —C. E. P. B.

A-1005 Ratcliffe, J. A. (Cavendish Lab. , Cambridge), Microscopic

mechanism for the absorption of radio waves in the ionosphere. (In: Beer, Arthur (ed. ), Vistas in Astronomy, pub. London,

1955-1956. Vol. 2:791-798. 5 figs. , 2 refs. , 30 eqs. ) DWB,

DLC—The paper deals with the absorption which occurs when a radio wave passes through a medium containing free electrons

which make collisions with heavy particles. It is shown that

the absorption can be accounted for in terms of the impulses
297

which the electrons radiate at each collision under the influence of the imposed wave. Although these impulses are ran- domly timed they correspond to a coherent wave of the re- quired amplitude and phase. --Author's abstract.

A-1006 Ratcliffe, J. A. , The formation of the ionospheric layers F-l

and F-2 . Journal of Atmospheric and Terrestrial Physics, London, 8(4/5): 260-269, May 1956. 4 figs. , 2 tables, 6 refs.

,

22 eqs. DWB--Detailed investigations of the electron distribution in the F2 region have recently shown (RATCLIFFE et al.

,

1956) that the F2 layer could be formed by the ionizing agency

which has its peak of electron production in the Fl layer, if the loss - coefficient varies with height in a certain way, ex- plained in the paper referred to. The implications of a losscoefficient varying in this way are examined in detail in the

present paper, and it is shown that it would explain the known

facts about the splitting of the F layer into separate Fl and F2

layers. The question of what determines the height of the F2

electron peak is also discussed. --Author's abstract.

A-1007 Ratcliffe, J. A. , Movements in the ionosphere. Nature, London, 177(4503): 307-308, Feb. 18, 1956. 3 refs. DWB-Account of Royal Astronomical Society discussion on Nov. 25,

1955. Drifts of electron irregularities show that phase of 12-

hr rotating component in E region advances by 5 /km from 85-

130 km and changes with seasons. Speed increases with

height. Fading movements agree with meteor trail movements

which are due to air motion. The cause of this is discussed.

In F region large scale ripples and small scale irregularities

travel with the same speed. Elongated (3 or 4:1) irregularities at 400 km which produce scintillation are discussed;

their true drift is towards SW. Some suggestions as to cause

were made. —C. E. P. B.

A-1008 Ratcliffe, J. A. , The ionosphere. Nature, London, 179(4555):

339-340, Feb. 16, 1957. DWB--Radio exploration of the ionosphere is described. Critical frequencies of E and Fl layers

agree with simple theory of production and recombination of

electrons, but in F2 layer diffusion of electrons by large scale

vertical movements is important. Changing patterns of reflected wave are attributed to moving irregularities caused by air

movements in E layer, but not in F region. Variations of ionizing radiation from the sun, 'sudden ionospheric disturbances'9 and ionospheric storms are discussed. Part played by ionospheric scatter in short wave communication is described. -- C £•• P. B.
298

A-1009 Ratcliffe, J. A. (Cavendish Lab. , Univ. of Cambridge),

The ionosphere. (In: Bates, D. R. (ed. ), The Earth and its

atmosphere. N. Y. , Basic Books, 1957. p. 204-222. fig.

)

DLC--Discovery of the ionosphere, production of ionized layers, propagation of radio waves through ionized air, proof of

existence of the ionosphere, ionospheric soundings, ionospheric observatories, h'(f) curves and critical frequencies, the

E and Fl layers, the peculiar F2 layer, electric currents in

the high atmosphere, horizontal movements of the ionosphere,

solar effects (ionospheric storms and SID's), and world-wide

ionospheric studies during IGY are discussed at some length

in a popular style. --M. R.

A-1010 Ratcliffe, J. A. (Cavendish Lab. , Cambridge Univ. ), Infor- mation by radio from the satellites. Institution of Electrical

Engineers, London, Journal, 4(47) -.603-608, Nov. 1959. 7

figs. , table, 2 refs. DLC—This article is a condensed form

of a lecture dealing with some exploratory results of ionospheric research as obtained by way of radio signals from or- bitting satellites, especially the Sputnik 1. The propagation

characteristics of the 20 and 40 Mc/s radio waves used permit deductions to be drawn with regard to orbital features,

ionospheric electron content, density and distribution, influence of earth's magnetic field, etc. Results deduced from

the Doppler effect and the Faraday effect are discussed and

shown in graphs. --W. N.

A-1011 Ratcliffe, J. A.; Robbins, Audrey R, etal., Movements in

the quiet E layer over Slough. Journal of Atmospheric and Terrestrial Physics, London, 15(1/2): 21 -26, Sept. 1959. 2 figs.

,

4 refs. , 4 eqs. DLC--Electron density profiles have been deduced from h'(f) curves recorded at Slough once per hour on

every day of each of six representative months. Allowance

was made for the effects of the earth's magnetic field and the

ionization below the F layer. The average behavior on magnetically quiet days is described and discussed, with particular reference to the possible magnitude and phase of vertical

movements in the F region. --Authors' abstract.

A-1012 Ratcliffe, J. A. (Cavendish Lab. , Cambridge), The highest

parts of the ionosphere. Royal Meteorological Society, Quarterly Journal, 85(366) :321 -331, Oct. 1959. 12 figs. DWB, DLC

--A paper describing the present ideas about the highest parts

of the ionosphere, above about 150 km, and how views about

these parts have developed in the past five years. Formerly,

it was thought that the formation process of F2 layers was the

same as that of E and Fl layers; a series of 'anomalies' and

'unknowns' connected with F2 layer has made the old explanation entirely unsatisfactory. Although no adequate explanation
299

has yet been set forth, recently, the determinations of atmospheric and electronic densities by rockets and artificial satellites, and the calculations of electron density distributions

from the h(f) curves indicate that a first order solution of the

problem may not be long delayed. The way then also will be

clear for a consideration of the anomalies in the F2 region,

and of the fundamental changes noticeable in it during ionospheric storms. The discussion is extensively illustrated by

graphical representations. --I. S.

A-1013 Ratcliffe, J. A. (Univ. of Cambridge), The magneto-ionic

theory and its application to the ionosphere . London, Cambridge Univ. Press, 1959. 206 p. figs. , tables, eqs. , bibliog. p. 193-201. Price: 40 Sh. DLC (QC661.R33). Review

in Royal Meteorological Society, Quarterly Journal, 85(365):

320, July 1959. Review by A. Scibor-Rylaki in Science Progress, London, 47(188): 776-777, Oct. 1959. Review by G.H.

Munro in Australian Journal of Science, Sydney, 22(4): 176,

Oct. 1959. --Account of the theories of radio wave propagation

through the earth's ionosphere and through the ionized envelopes of radio stars, being concerned with the propagation of

electromagnetic waves through a partially ionized gas in the

presence of a magnetic field. The author is not content to

follow a simple mathematical approach but searches for physical reasons for the behavior of the waves. Two approaches

have been adopted: a macroscopic one in which the properties

of the medium are averaged out and a microscopic one based

on the motion of individual electrons. Ch. I treats the derivation of the equations, the microscopic approach, the physical reason for the characteristic waves and their dispersion,

the absorption or the "macroscopic" theory and the microscopic

picture of absorption. In Pt. II, the results are summarized in

graphical form and simple rules demonstrated for computing

curves of refractive index and absorption index as functions of

electron density. Pt. Ill treats applications of the theory to

the earth's ionosphere and mentions a wide range of phenomena

capable of explanation in terms of the magneto-ionic theory of a homogeneous medium. Finally, the author discusses a number of relevant miscellaneous topics, including the relationship between the anisotropic behavior of the atmosphere and

that of transparent crystals. A complete bibliography and an

alphabetical index of subjects are included in this excellent

work. --A. V.

A-1014 Ratcliffe, J. A. (Cavendish Lab. , Cambridge Univ. , England),

Ionizations and drifts in {he ionosphere. Journal of Geophysical Research, Wash., D. C, 64(12) :2102-2111, Dec. 1959.

9 figs. , 7 refs. , 15 eqs. DLC--Our knowledge of the vertical

distribution, and the horizontal irregularities and movements,
300

of electrons in the ionosphere is summarized. The mechanism

by which electrons can be moved either by the movement of

the surrounding air or by electric fields arising from charges

elsewhere in the ionosphere is discussed. The statistical description of a randomly moving distribution function which is

commonly used by investigators of the ionosphere is described.

--Author's abstract.

A-1015 Rawer, Karl, Ausbreitunqsvorhersage fur Kurzwellen mit

Hilfe von Ionospharenbeobachtungen. (Forecast of short wave

propagation conditions^through ionospheric observation. ) Archiv der Elektrischen Ubertragung, 5(4):154-167, April 1951.

14 figs. , 40 refs. , 18 eqs. DLC--Following a brief review of

empirical methods for calculation of field intensity with res- pect to M. U. F. , the development of the so-called '^German

method" is discussed. Geographic location, time of day and

year, and sunspot cycle are factors treated separately. --W. N.

A-1016 Rawer, Karl; Bibl, Klaus and Argence, Emile, Sur la deter- mination des nombres de chocs des regions E et F de 1 'ionosphere. (On the determination of collision frequencies in the

E and F regions of the ionosphere. ) Academie de Sciences,

Paris, Comptes-Rendus, 233(12): 667-668, Sept. 17, 1951.

refs. , eqs. DWB--During Nov. 1949 - April 1950, and Feb.

1951, 32 nighttime observations were made of the F region at

4 frequencies. The number of echoes have been analyzed and

coefficients established according to usual methods. The decrease in absorption and the effect of focalization have been

considered in the calculations. A similar series has been obtained from noon data for five frequencies in the E region. The

variation of absorption and the influence of absorption is calculated. --M. R.

A-1017 Rawer, Karl, Calculation of sky-wave field strength. Wireless Engineer, London, 29(350) :287-301, Nov. 1952. 17 figs.,

30 refs. , 25 eqs. DLC--A method for the calculation of the

field of the skywave, based upon the contributions of the different transmission paths, has been applied since 1940. It takes account of the effects of the lower ionospheric layers,

such as absorption and cut-off, and of the geometrical optics

of the reflecting layer. The trend of actual development in

this field seems to be that former integral formulas are replaced by such differential methods. --Author's abstract.

A-1018 Rawer, Karl, Die Ionospharectihre Bedeutung fur Geophysik

und Radioverkehr. (The ionosphere: its importance in geophysics and radio communication. ) Groningen, P. Noordhoff, 1953.

179 p. 67 figs. , 143 refs. , 68 eqs. DLC--A complete text on

the use of radio in ionospheric research. Ch. I takes up methods of observation by echoes, spectroscopic methods for aurora
301

and airglow, magnetic, meteor and luminous night clouds, and

soundings; Ch. II gives results of observations by echo methods, magnetic data, composition, pressure, density and temperature. Ch. Ill discusses theories of ionospheric stratification (origin and disappearance of ionization and explanation of

different layers. Ch IV takes up normal and irregular changes

of the ionosphere (D, E, F2, F, £2, G and Es and influence of

magnetic storms, eclipses, polar summer and night, commencements). Ch. V discusses influence of ionosphere on propagation of radiowaves and forecasting propagation. --M. R.

A-1019 Rawer, Karl, L'effet de l'eauateur maanetiaue sur l'ionisa - tion de la couche Es. (Effect of the magnetic equator on the

ionization of the sporadic E region. ) Academie des Sciences,

Paris, Comptes Rendus, 237(18): 1102-1 104, Nov. 2, 1953.

4 refs. DWB—The frequency of sporadic ionization at the magnetic equator only occurs with respect to the centers of "ionization clouds" and not for minimum ceiling. The effect only

takes place during daytime. --Author's abstract (trans.).

A-1020 Rawer, Karl and Argence, Emile, Sur les ph^nomenes de focal - isation dus a la houle ionospherigue et la determination du nom- bre de chocs. (Focalization phenomena caused by ionospheric

tides, and determination of the number of collisions. ) Academie des Sciences, Paris, Comptes Rendus, 239(17): 1066-1067,

Oct. 27, 1954. 6 refs. DWB--Certain ionospheric phenomena

(like a secondary echo having larger amplitude than the primary one) cannot be explained by the customary hypothesis of a plane stratified ionosphere. Such phenomena may be ac- counted for by the assumption of a wave motion of the reflecting surface. The author presents an equation for deriving ionospheric curvature from amplitudes of triple echoes. The new

approach considerably affects various values deduced from

ionospheric measurements. --G.T.

A-1021 Rawer, K. (Ionospheric Stat. , of S. P. I. M. , France, Neuershausen, Freiburg, Ger. ), Some remarks concerning ionosph- eric absorption work. Journal of Geophysical Research, Wash.,

D. C. , 60(4): 534-535, Dec. 1955. fig. DLC-Monthly mean

absorption decrements in E layer and daily values also, do not

support assumption of a horizontally stratified plane ionosphere whose total absorption is characterized by an effective re- flection coefficient. Focusing effects arising from curvature

in the reflecting layer produce an apparent reflection coefficient

greater than 1. Effect is only important in vicinity of focusing

areas. Night F2 observations showed negative absorption decrement in 30% of cases. Even in daytime, 2 or 3 daily observations show important focusing. These areas are illustrated as being in the form of inverted ripples. --M. R.
302

A-1022 Rawer, Karl, L'intensite du rayon dit de Pedersen. (Intensity of the Pedersen beam. ) Academie des Sciences, Paris, - Comptes Rendus, 243(11): 797-798, Sept. 10, 1956. table.

DLC--Ionospheric communication between two points may be

established by two different beams, the one with the steeper

angle of emission being called Pedersen beam. It is shown

in this paper that (as generally known) the Pedersen beam

usually has lower intensity than the regular beam. At cer- tain frequencies, however (for example f -£ 8. 2 MHz) this

intensity relation can be reversed, which is attributed to a selective absorption effect. --G.T.

A-1023 Rawer, K. , Focusing on a "rippled" ionosphere. Journal of

Atmospheric and Terrestrial Physics, London, 8(4/5): 296, May

1956. 4 refs. , eq. DWB--Gives revised formulas for spherical "ripples" showing values of H/r for which focusing exists.

--C. E. P. B.

A-1024 Rawer, K. and Suchy, K. , Aguivalenztheoreme bei der Wel- lenabsorption im Plasma. (Equivalence theorem in wave absorption by plasma. ) Annalen der Physik, Ser. 7, l(4/5):255-

260, 1958. 7 refs. , 23 eqs. --Two calculations, one based on

wave theory and one on radiation theory, show that (disregarding the geomagnetic field) Martyn's theory of ionospheric absorption is valid only if the attenuation is mostly due to collision and proportional to collision frequency. --Trans, of Authors' abstract.

A-1025 Rawer, K. (Ionosphere Inst. Rhein, Germany), Correlation

of Es characteristics in time and space. AGARDograph, Paris,

No. 34:67-80, Sept. 1958. 11 figs. , 10 refs. DWB (629. 1323

N864a)--The main parameters used to characterize an Es layer

are now precisely enough defined as foEs and fbEs. Nevertheless the values of these parameters are not representative,

since heavy fluctuations appear quite often. A better description can be given when the correlation functions in space and

time are determined. This has been done provisionally; a cor- relation distance of about 200 km, and a correlation time of

about 1 h for foEs and Vz h for fbEs has been found. --Author's

abstract.

A-1026 Rawer, Karl, The ionosphere: its significance for geophysics

and radio communications. Trans, by Ludwig Katz. N. Y. , Frederick Ungar, 1957. 202 p. 72 figs. , bibliog. p. 191-

198, 68 eqs. DWB (M10. 535 R257io). Review by E. V. Appleton in Journal of Atmospheric and Terrestrial Physics, London, 12(2/3) :223, 1958. Review in Institution of Electrical

Engineers, Journal, 4(44) :463, Aug. 1958. Review by T. W.

Bennington in Nature, 182(4643): 1116, Oct. 25, 1958.
303

A translation of the 1953 German text covering methods of observation of the ionosphere (radio, spectroscopic, geomagnetic, meteor and noctilucent clouds); results of echo soundings

and geomagnetic observations, (composition of air, excitation,

pressure and density, temp. , ionization); theory of layer formation, de-ionization, etc. ), regular and irregular changes

and the influence of the ionosphere on propagation and prediction of propagation conditions.

A-1027 Rawer, K. , Hauteur et epaissaur de la couche ionospherique

E. (Height and thickness of the ionospheric E layer. ) Annales

de Geophysique, Paris, 15(4) -.547-550, Oct. /Dec. 1959. 3

figs. , 5 refs. DLC--A method is presented concerning the

transformation of the "virtual heights" of ionograms into true

heights for the E region, by resolving the integral equation

which determines the electron density distribution as a function of height. This transformation makes it possible to study

the height variations of the ionosphere. It is shown that the

vertical motions in the F region may be continued in the E re- gion. The daily variation of the maximum ionization appears

clearly. The thickness of the layer decreases with the decrease of the solar zenith distance. The minimum virtual

height increases in the morning and evening; on the contrary

the true height of the lower boundary of the E layer seems to

be rather little variable during the day. The author concludes

that the variations of ionization may not be expressed by

means of a simple continuity equation if the exchange effects

in the E region are not taken into account. --A. V.

A-1028 Reber, Grote (Wailuku, Maui, Territory of Hawaii), Spread

F over Hawaii. Journal of Geophysical Research, 59(2) :257-

265, June 1954. 5 figs. MH-BH--The random variations of intensity of signals from point sources caused by the ionosphere

greatly affect studies of cosmic static. One cause of these

fluctuations is the condition known as spread F, which indicates the presence of diffuse and irregular echoes from the F

region of the ionosphere. Analyses of spread F over Hawaii

were completed for the period 1944-1953. The diurnal and seasonal properties are discussed, and a conclusion is reached

regarding latitude and longitude effects. Some properties of

scintillations at decameter waves are described. --Author's

abstract.

A-1029 Reddy, C. A. ; Rao, B. Ramachandra and Rao, M. S. , Mag- neto-ionic fading in pulsed radio waves reflected at vertical

incidence from the ionosphere. Institution of Radio Engineers,

Journal, 18(11): 669-675, Nov. 1958. 2 figs. , 4 tables, 5

refs.
304

A-1030 Rees, M. H. (Univ. Alaska, College, Alaska) and Rense,

Wm. A. (Univ. Colo., Boulder, Colo. ), Note on the cause

of ionization in the F region. Journal of Geophysical Research,

Wash., D. C. , 64(9):1251-1255, Sept. 1959. 2 tables, 15

refs. , 7 eqs. DLC--Recent rocket data on the intensity of the

solar 303. 8 A Hell line at the 140 km and 212 km level of the

upper atmosphere are utilized to investigate the possibility

that this radiation may be largely responsible for the heating

and ionization effects in the F region. Electron densities at

140 km and at 212 km are computed on the basis that the 303. 8

A photons ionize oxygen atoms. The computed results compare favorably with observed values of electron densities measured at these heights on ionograms taken at the same time as

the rocket flight which yielded the 303. 8 A intensity data.

-•Authors' abstract.

A-1031 Reid, G. C. and Collins, C. (both, Defence Res. Board,

Ottawa, Canada), Observations of abnormal VHF radio wave

absorption at medium high latitudes . Journal of Atmospheric

and Terrestrial Physics, London, 14(1/2): 63-81, April 1959.

7 figs. , table, 23 refs. , eq. DLC--A study of cosmic noise

absorption at a frequency of 30 Mc/s at Ottawa and Churchill

has revealed the existence of two apparently distinct types of

abnormal absorption event. One of these is predominantly a night-time phenomenon and is closely associated with auroral

and geomagnetic disturbance. It is suggested that this absorption may be caused by an increase in electron collisional

frequency at E region heights rather than by a large increase

in electron density at lower levels. The second type of absorption is confined to the auroral zone and is predominantly

a daytime phenomenon, recurring for several days after a large

solar flare. Evidence is presented to show that this absorption is due to an increase in ionization at very low levels in

the ionosphere. The cosmic noise measurements are supported

by evidence from a number of VHF forward-scatter circuits in

Canada, and this is used to obtain information about the geographical extent and frequency of occurrence of these abnormal

absorption events. --Authors' abstract.

A-1032 Renau, J. (Cornell Univ. , Ithaca, New York), A theory of

spread F based on a scattering-screen model. Journal of Geophysical Research, Wash. , D. C. , 64(8): 971 -977, Aug. 1959.

8 figs. , 10 refs. , 4 eqs. DLC—To shed some light on the phenomenon of spread F, a thin scattering screen is postulated above the E region. The virtual height which is associated with

a pulse radiated from the sounder, forward scattered by the

screen and then reflected back to the sounder via the F region,

is calculated. For frequencies appreciably larger than the

penetration frequency, the minimum virtual height versus the
305

operating frequency, on a linear scale, is a straight line, the

slope of which depends on the height of the screen. As the

height of the screen increases, the slope decreases. When

the scattering screen is assumed at the level of reflection, the

slope of the line coincides with the tangent from the origin to

the regular vertical-incidence trace. Experimental ionograms

are presented that fit with the suggested mechanism. -•Author's abstract.

A-1033 Revellio, Karl, Die atmospharischen Storunaen und ihre

Anwenduna zur Untersuchuna der unteren Ionosphare. ( Atmos

pheric disturbances and their application in the study of the

lower ionosphere. ) Weissenau, Germany, Max Planck-Institut fur Physik der Stratosphare, Mitteilungen, No. 6, 1956.

54 p. 82 figs. , 46 refs. , eqs. German summary p. 1. DWB

(10. 53 W433m) --Atmospheric disturbances (atmospherics) may

provide information on the state of the lower ionosphere in different ways. Their form makes it possible to determine the

height of reflection and distance of the center by considering

the multiple reflections from the ionosphere and the ground.

The decrease in pulse amplitude with the number of reflections

is an indication of reflection coefficients and electron densities. The variety of pulse forms makes it difficult to interpret

such forms, but all wave forms can be reduced to a reflection

model. The rate of occurrence of disturbances is strongly dependent on frequency, time of day and season. Phenomena at

sunrise were clarified by comparison with field strengths of

signals received from a sender. They give indications of the

UV-absorbing region at the upper limit of the ozone layer. During the solar eclipse of June 30, 1954 an increase in the number of atmospherics was observed and from this fact a decrease

of attenuation in the lower ionosphere was deduced. --Transl.

of author's abstract.

A-1034 Revirieux, P. and Lejay, P. , On the localization of the spo- radic E-ionized region of the upper atmosphere. Academie de

Sciences, Paris, Comptes Rendus, 227, 79, 1948. -In June,

1948, good 2-way low-power communication at frequencies

near 60 Mc was maintained for several hours between amateur

stations near Paris and others in (a) Czechoslovakia (June 27X

(b) South Norway (June 28), (c) South Sweden (June 29). Such

long distance communication could not be established with any

other stations during the periods concerned. On June 7 longdistance communication in the 60 Mc band could only be es- tablished with Algeria. These results indicate the existence

of sharply localized ionization zones which move slowly and

are situated roughly midway between Paris and the places with

which radio contact on these frequencies is possible. Movement of such an ionization zone was noted on June 4 between
306

1630 and 2000 G. M. T., when communication was carried out

successively between Paris and (a) northern countries, particularly Sweden, (b) Denmark, (c) Czechoslovakia, (d) Switzerland and Italy, (e) French stations near the Mediterranean,

(f) Algeria. Lejay stated that particularly strong sporadic E

was recorded at Bagneux in two periods which coincide precisely with those noted above. The sporadic E upper frequency

limits, on the afternoon of June 4 and the morning of June 5,

exceeded the highest frequency (13 Mc) available for the Bagneux transmitter. Between June 24 and 29, the upper limits

were not so high, but many multiple echoes were noted, particularly on June 26 and 2 7. The amateur observations supply valuable information as to the situation and extent of a phenomenon whose cause is at present uncertain; such information is not given by vertical soundings of the ionosphere.

A-1035 Rice, P. L. and Daniel, F. T. , Radio transmission loss ver- sus distance and antenna height at 100 Mc. U. S. National

Bureau of Standards, NBS Report, No. 3520, Jan. 1, 1955.

Supplement 8. 25 p. 11 figs. , tables, 7 refs. , 4 eqs. DWB

--This report describes curves of transmission loss versus distance and antenna height derived from an analysis of approximately 159, 000 hourly median field strength observations between 90 and 110 Mc. These observations extend over a period of several years and are distributed geographically over

the whole U. S. The curves contained in this report are believed to be more precise for engineering use than the FCC Ad

Hoc Committee curves published in 1949, the only curves of

this character generally available up to now. --Authors' abstract.

A-1036 Richter, K. H. , Ergebnisse aus Radar-H#henwindinessunqen

in Hannover-Lanqenhaqen. (Results of radar upper wind measurements in Hanover-Langenhagen. ) Germany. Deutscher

Wetterdienst in der US-Zone, Berichte, No. 42:331-338, 1952.

7 figs. , 4 tables, 7 refs. DWB--Mean scalar and vector wind

velocities at levels ground to 80 mb tabulated monthly June

1948-May 1949 are discussed in detail. Steadiness computed.

Diurnal variation of scalar velocity (winter, summer, year)

shown by isopleths (maximum around 300 mb, 2 h in winter,

10 h in summer and year. )--C. E. P. B.

A-1037 Riggs, L. P. and Bean, B. R. , Radio meteorological data

available as of April 1, 1958. U. S. National Bureau of

Standards, NBS Report, 5565, April 7, 1958. 18 p. tables.

DWB (621.384 U585ra)--The past lew years have seen a rapid

increase in the amount of research on the utilization of standard weather observations for radio propagation studies, with
307

occasional unnecessary duplication of effort or noncompatibility of basic parameters. An effort was made to remedy this

situation at the First Meeting on Radio Climatology held at

the Central Radio Propagation Laboratory on Jan. 15, 1958.

One of the important conclusions of this meeting was that

CRPL should act as a clearing house and maintain a listing of

data obtainable from various laboratories. The present report

is the first such listing of these data. -•Authors' abstract.

A-1038 Rastogi, R. G. (Physical Res. Lab. , Ahmedabad, India),

A study of the noon critical frequencies of the E and F 1 layers

of the ionosphere. Geofisica Pura e Applicata, Milan, 40:145-

156, 1958. 15 figs. , table, refs. DWB-The mean monthly

noon critical frequencies of the E and Fl layers of the ionosphere at a number of stations in different latitudes and their

variation with sunspot number have been studied. It was

found that while the E layer approximates a Chapman region,

the Fl layer is markedly affected by other agencies, somewhat similar to F2. In high sunspot years, foFl shows two

maxima at middle latitudes with a minimum at the equator. -- Author's summary.

A-1039 Rivault, R. (Faculte des Sci. , Poitiers), Caracteristiques

des sifflements observes au cours d'une annee. (Characteristics of whistlers observed in the course of one year. ) L'Onde

Electrique, Paris, 37(362): 539-540, May 1957. fig. DLC--

Frequency and wave-form characteristics of whistlers were re- corded at Poitiers, France. Two types were identified: those

of short duration (connected with thunderstorm activity in the

Southern Hemisphere) and those of longer duration (preceded

by an atmospheric of a particular type associated with lightning in the Northern Hemisphere). Wave forms of long whistlers would indicate that they are closely connected with the

mechanism of formation of the sferics which precede them. -- G.T.

A-1040 Rivault, R. , Perturbations radioelectriques d'origine terres - tre (Commission IV. XIIeme Assemblee Generate de 1 'Union

Radio Scientifique Internationale). (Radioelectric disturbances of terrestrial origin: (Report of) Commission IV, Xllth

General Assembly of the International Scientific Radio Union.

)

L'Onde Electrique, Paris, 38(376): 527-532, July 1958. 62 refs.

DLC--Report on the results and researches presented by mem

bers of Commission IV at the Xllth General Assembly of the

International Scientific -radio Union. The development mentioned three years ago is now confirmed by the abundance of

new results in connection with whistlers and natural low-frequency emissions. Thanks to these phenomena, one can already explore the exosphere which will, in the near future,
308

be sounded as one now sounds the ionosphere. The author

summarizes the results obtained in research on parameters

modifying the shapes of atmospherics, when studying lightning and whistlers and low-frequency transmissions. He finally explains the researches made in connection with statistical and goniometrical recording of atmospherics, and also

those regarding the meteorological aspects of atmospheric observations. --A. V.

A-1041 Roberts, C. R. ; Kirchner, P. H. and Bray, D. W. , Radio

reflections from satellite-produced ionization. Institute of

Radio Engineers, Proceedings, 47(6): 1156-1157, June 1959.

A-1042 Robbins, Audrey R. and Thomas, J. O. (both. Cavendish Lab.,

Cambridge), The disturbed F layer over Slough. Journal of

Atmospheric and Terrestrial Physics, London, 15(1/2): 102-107,

Sept. 1959. 6 figs. , 8 refs. DLC--Electron density profiles

for magnetically disturbed days have been compared with those

for quiet days. The effect of disturbance on the height of the

peak of the F2 layer (hmF2), on the maximum electron density

(Nm) and the total electron content below the F2 layer peak

(nf) is discussed. It is emphasized that the quantity h'F2 frequently used in the past in describing the effect of disturbance

is without physical significance, and can be seriously misleading. Evidence is presented to show that appreciable changes

sometimes occur in the ionosphere near the time of a magnetic

sudden impulse. --Authors 8 abstract.

A-1043 Rogers, G. L. , A new method of analysing ionospheric move- ment records. Nature, London, 177(4509) :613-614, March 31,

1956. 2 figs. , 10 refs. , 2 eqs. DWB--A process is described

for scaling down a radio wave pattern for optical examination.

It is suitable for investigating a smooth reflecting ionosphere

with small imperfections moving across or below it. The method was tested in Wellington, N. Z. It shows that objects far

below the ionosphere can make significant contributions to

ionospheric movement records. --C. E. P. B.

A-1044 Rogers, G. L. , Diffraction microscopy and the ionosphere.

Journal of Atmospheric and Terrestrial Physics, 10(5/6):332-

337, 1957. fig. , table, 11 refs. DWB--The application of diffraction microscopy to Mitra records is considered. It is

shown that its application to existing records might result in

some slight improvement, probably scarcely justifying the effort. If, however, tests should show that the combination

would work with aerial spacings of 3-10 A , the advantages

of the combined method would be substantial. An important

practical limitation on any type of Mitra method is the complexity of the record normally obtained, and it may prove
309

impossible to analyze adequately any but the simplest of them

by any technique. The question of future development is

briefly touched on. --Author's abstract.

A-1045 Romell, Dag, Influence du deplacement vertical des couches

ionisees sur la frequence des ondes radioelectriques . (Influence of vertical displacement of the ionized layers on the frequency of radio-electric waves. ) Academie des Sciences,

Paris, Comptes Rendus, 226(12): 1007, March 22, 1948. DLC,

DWB--Theory that the ionized layers themselves, not the ionized gas, moves rapidly in a vertical sense. Possible effect

of winds in the high atmosphere. (Doppler effect).

A-1046 Ross, W. and Bramley, E. H. , Tilts in the ionosphere. Nature, London, 164(4165 ):355, 1949. —Simultaneous observations

were made with two direction finders 10 km apart, on signals

from a transmitter 700 km further north. Bearings taken during

the day on hf signals reflected from the F region show fluctuations of a few degrees from the true great-circle bearing. These

fluctuations have a period of 10 to 30 min, and are attributed

to a tilting or wrinkling of the reflecting layer. The fluctuations were similar at both receiving stations, showing that a

tilt of about 4 from the horizontal was substantially uniform

over a distance of 5 km.

A-1047 Ross, W. J. , Ionospheric investigation from satellite radio

observations, Pt. 1. Doppler effect recording instrumentation.

Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF 19(604)-4563, Scientific Report No. 120, June 30,

1959. 81 p. 24 figs. , eqs., 14 refs. DWB (M10. 535 P415i)

--A brief survey is made of the main features of satellite transmitters and of the ionospheric propagation effects produced in

the radio waves from them. From these considerations the desirable properties of the transmitter are summarized and the

necessary properties of the receiving apparatus are inferred.

Detailed descriptions of the various units of the receiving instrumentation are then given, followed by the presentation of a sample record analyzed to yield electron content of the ionosphere. --Author's abstract.

A-1048 Row, Ann L. , Upper winds over Auckland. New Zealand.

Meteorological Service, Circular Note, No. 78, 1952. 1 p

+ 5 tables. GB-MO--Seven years of radar wind observations

at Auckland are used to derive monthly means, resultant winds

and the seasonal frequency distribution for 10, 000, 18, 000,

30, 000 and 40, 000 ft levels. -G. J. E.
310

A-1049 Roy, R. and Verma, J. K. D. (Inst, of Nuclear Physics,

Calcutta), Irregularities in the ionosphere. Journal of Geophysical Research, 58(4): 473-485, Dec. 1953. fig. , 12 plates,

refs. DLC —Electron clouds, both in the E and F regions of the

ionosphere have been detected at vertical incidence by means

of a high-precision ionosphere sounding equipment. The clouds

give rise to scattered echoes, which are delineated on an ex- panded sweep as individual pips, resolved out from the normal

echoes. An estimate of the received power by back-scattering,

made on the basis of the theory of tropospheric radio scattering by BOOKER and GORDON, shows that it is far in excess

of the receiver noise power. Some of the records indicate that

sometimes at night the normal layer structure of the ionosphere

ceases to hold; the ionospheric regions then contain only electron clouds at different heights. The scattered echoes generally appear for a very short duration. The short persistence

(1 to 2 minutes) of these echoes has been explained by considering the drift of the clouds by the upper air winds. --Authors' abstract.

A-1050 Roy, R. and Verma, J. K. D. (Inst. Nuclear Physics, Calcutta, India), Polarization of electromagnetic waves for vertical propagation in the ionosphere. Journal of Geophysical

Research, Wash., D. C. , 60(4): 457-482, Dec. 1955. 17 figs.,

3 plates (photos), numerous egs. 19 refs. DLC—A theoretical

study of the variation of the state of polarization of a vertically incident electromagnetic wave while in propagation in

the ionosphere has been made on the basis of an approximate

solution of the wave equations obtained by Saha, Banerjee,

and Guha. It has been shown that the major axes of the polarization ellipses of both the ordinary and the extraordinary

waves would lie in the N-E quadrant in the Northern Hemisphere and in the N-W quadrant in the Southern Hemisphere. A

new method has been outlined for the determination of the electron density and the collision frequency in the ionized layers

from the value of the tilt-angle and the ratio of axes of the

elliptic patterns. An analysis of the characteristics of the

experimentally observed polarization patterns indicates that

in E layer the value of v is 1. 7 X 10® per second. They further show that the polarization of the downcoming waves cor- responds to their respective reflection levels, rather than a

limiting region below the E layer. --Authors' abstract.

A-1051 Rudloff, D. , Ionospharensturm und Wetterfunkdienst am 4.

September 1958. (Ionospheric storm and weather broadcasting

Service on September 4, 1958. ) Wetterlotse, Hamburg, No.

136:221-223, Sept. 1958. DWB--Ship observations of the phenomena which for hours silenced radio transmission over a large

area, is discussed briefly. --W. N.
311

A-1052 Rumi, G. C. (Geophysical Inst. , College, Alaska), VHF

radar echoes associated with atmospheric phenomena. Journal of Geophysical Research, Wash. , D. C. , 62(4): 547-564,

Dec. 1957. 3 figs. , (11 photos), 34 refs. , 3 eqs. DLC--

VHF radar observations during the summer and the fall of 1955

at Ithaca, N. Y. , gave useful information not only about lightning, meteors, and aurora, but also about the possible existence and characteristics of "upward discharges" from the top

of the troposphere to the bottom of the ionosphere. A radar

operated at 27. 85 Mc/sec was used. A feature was the photographing from magnetic tape records that were played back to

reproduce the original oscilloscope presentation. This technique proved to be useful in permitting more detailed analysis

than had previously been possible. Photographs are presented

that show examples of echoes (in an amplitude-vs -time display)

that we have attempted to associate with "upward discharges. " (Photographs of a simple meteor echo and of a meteor echo embedded in an auroral echo are also included, ) Detailed analysis led us to dissociate many of our echoes from meteors.

Their rise and decay speeds, their duration, their flatness,

their ranges of appearance, and the observed repetitions suggested that "upward discharges" from troposphere to ionosphere

could have been responsible for the reflection of radio waves.

Nevertheless meteors cannot be ruled out of a complete picture of the phenomenon. Meteors may play a role in the generation of "upward discharges" as triggering agent. --Author's

abstract.

A-1053 Rumsey, N. J. (Dominion Physical Lab. , Lower Hutt, New

Zealand), Curvature -induced error in the analysis of fading

records. Journal of Atmospheric and Terrestrial Physics,

London, 11(3/4): 255-258, 1957. 2 figs. , 10 refs. , eqs. DLC

--Curvature of lines of maximum amplitude in a radio fieldstrength pattern drifting across an array of three receivers

can introduce an error into the estimate of the drift velocity,

but the error is expected to be large only infrequently. The

mean error is smaller for an array of receivers at the corners

of an equilateral triangle than for one at the corners of a rightangled triangle. --Author's abstract.

A-1054 Rydbeck, Olof E. H. , A theoretical survey of the possibilities of determining the distribution of the free electrons in the

upper atmosphere. Trans. Chalmers Univ. of Technol, Go'teborg, Sweden. Chalmers Tekniska Hdgskola, Handlingar

(Transactions), No. 3, 1942.
312

A-1055 Rydbeck, Olof E. H. , On the propagation of radio waves.

G6teborg, Sweden. Chalmers Tekniska Hdgskola, Handlingar

(Transactions), No. 34, 1944. 168 p. 47 figs., 5 tables,

26 refs. , 274 eqs. DLC--A theoretical study of transmission

properties of the parabolic layer (also as seen from the ionosphere) throughout long, medium and short wave ranges. An

expansion of wave functions enables accurate investigation

of L. T. Eckersburg's phase integral method. --W. N.

A-1056 Rydbeck, Olof E. H. , A simple Kerr modulator for ionospheric recording. G<$teborg, Sweden. Chalmers Tekniska Hdigskola, Handlingar (Transactions), No. 44, 1945.

A-1057 Rydbeck, Olof E. H. , On the spherical and spheroidal wave

functions. Go'teborg, Sweden. Chalmers Tekniska Hogskola,

Handlingar (Transactions), No. 43, 1945.

A-1058 Rydbeck, Olof E. H. , The theory of the traveling wave tube.

Go'teborg, Sweden. Chalmers Tekniska Hogskola, (Report

from the Research Lab. of Electronics) 1947.

A-1059 Rydbeck, Olof E. H. , On the propagation of waves in an in- homogeneous medium. I. Go'teborg, Sweden. Chalmers Tekniska Htfgskola, Handlingar (Transactions), No. 74, 1948.

A-1060 Rydbeck, O. E. H. (Chalmers Univ. of Technology, Gothenburg, Sweden), Magnetic ionic triple splitting. International

Council of Scientific Unions. Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 182-

201. 16 figs. , 6 refs. , 9 eqs. , p. 200-201. DWB--A fundamental paper giving a summary of the theory and results of detailed investigations of the mechanism of excitation of the E

and F layer triple splits (third mode or Z-trace) which appear

on ionospheric records. The data are taken from records made

at the Kiruna Ionospheric and Radio Wave Propagation Observatory at 67 50*N and 20°14'E. Graphs show variation of critical collisional frequency with geomagnetic latitude and illustrative recorder records of triple splits. It is not necessary

to assume any sudden change in electron density with height

to explain the phenomenon. A more detailed report is given

by the author in 1950 paper. --M. R.

A-1061 Rydbeck, Olof E. H. , Forsgren, Sven K. H. , On the theory

of electron wave tubes. Go'teborg, Sweden. Chalmers Tekniska Hogskola, Handlingar (Transactions), No. 102, 1951.

A-1062 Rydbeck, Olof E. H. , The theory of magneto ionic triple split- ting. Go'teborg, Sweden. Chalmers Tekniska H6*gskola, Handlingar (Transactions), No. 101, 1951.
313

A-1063 Ryle, M. and Hewish, A. , The effects of the terrestrial ion- osphere on the radio waves from discrete sources in the galaxy. Royal Astronomical Society, Monthly Notes, 110(4):381-

394, 1S50. --The existence of irregular refraction processes in

the ionosphere causing rapid fluctuations in the intensity of

the radiation at the ground have been observed. Using antennas of high resolving power showed that the apparent position

of a source may vary irregularly by 2 or 3 minutes of arc. The

incidence of these irregularities shows a marked diurnal variation; maximum at about 01 h 00m local time. Accounting for

the irregularities in the ionosphere an alternative mechanism

based on the interception of interstellar matter moving under

the gravitational attraction of the sun, rather than solar emission is suggested and may contribute toward closer information of accretion of matter by the sun. --From authors' abstract.

A-1064 Sacco, L. , La distribuzione statistica della intensita dei

segnali radio propogati nella troposfera e nella ionosfera.

(The statistical distribution of field strength of radio signals

propagated in the troposphere and the ionosphere. ) Poste e Telecommunicazioni, Rome, 22(2):55-72, Feb. 1954. 4 figs. , 21 refs. , 56 eqs. DLC--An examination is made of the types

of distribution in time which best represent the fluctuations of

radio signals traversing the troposphere and the ionosphere.

The distributions considered are (a) normal, (b) log normal,

(c) fluctuations due to interference (Rayleigh distribution),

and (d) fluctuations due to polarization variations. Gamma

and phase distribution are discussed and the concept of cor- relation is introduced. --I. R. E. , Proceedings, No. 3020, Nov.

1954.

A-1065 Sachdev, D. K. (Radio Propagation Unit, Natl. Physical Lab.,

New Delhi), Study of the atmospheric radio noise at 27 and

100 kc/s at Delhi. Journal of Scientific and Industrial Research, Sec. A, 17(7):262-270, July 1958. 12 figs. , table,

8 refs. , 2 eqs. DLC--A preliminary report of the observations

on VLF atmospheric radio noise being carried out by the Radio

Propagation Unit, National Physical Laboratory of India, New

Delhi (28. 5 N, 77 E) is presented. Measurements are cur- rently made at two frequencies, namely 27 kc/s and 100 kc/s.

Diurnal and seasonal variations of the radio noise indicate appreciable ionospheric attenuation during day-time, and a summer afternoon maximum, possibly associated with local thunderstorms. Noise intensity falls rapidly during the early morning hours, the 'sunrise time' differing greatly from one day to

another. The sunrise fall is sharper at 100 kc/s than at 27

kc/s. Long period (2 hr) fading is observed on certain nights.
314

and is believed to be associated with disturbed conditions in

the ionosphere. Particular attention has been given to the

study of sudden enhancement of atmospherics (S. E. A. ) for

which the observations were initially undertaken. It is found

that enhancement is observed at both frequencies at the time

of a solar flare; the effect at 27 kc/s is normally larger and

earlier than at 100 kc/s. However, there is no one-to-one

correspondence between the S. E. A. and the solar flare. Further, cases have been observed when the S. E. A. at 100 kc/s

is found to be larger than at 27 kc/s. From the present observations it is suggested that transition from enhancement to

fadeout occurs somewhat beyond 100 kc/s. --Author's abstract.

A-1066 Saha, A. K. and Ray, S. , Some features of the E2 layer observed at the ionosphere field station, Haringhata, Calcutta.

Journal of Atmospheric and Terrestrial Physics, 7(1/2):107-

108, Aug. 1955. 3 figs. , 2 refs. DWB--The automatic ionospheric recorder normally shows a thick extensive E2 layer in

daytime. It usually originates at Fl level at or after 13 h

LMT and descends to merge with El layer. --C. E. P. B.

A-1067 Saha, M. N. ; Banerjea, B. K. and Guha, U. C. , Vertical

propagation of electromagnetic waves in the ionosphere.

National Institute of Sciences of India, Proceedings, 17(3):

205-226, May/June 1951. 8 figs. , 3 tables, 11 refs. , 3 eqs.

DWB--A theoretical and detailed discussion of various equations for the vertical propagation of radio waves in the ionosphere, with stress on the nature of the modification at high

latitudes. The coupling term 5> and the polarization quantities Pi and P2 are discussed in minute detail whereas the two

refractive indices ^e and <£ are not discussed as they were

previously treated in detail by other workers. It is shown

that 3? can De neglected anywhere, except very close to the

geomagnetic poles, so far as F layer propagation is concerned,

but E layer propagation is more complicated. As an exact

treatment of the differential equation is yet to be made, the

nature of the modification of propagation as a function of ^> on

the triple splitting cannot be definitely stated. --W. h.

A-1068 Sales, G. S. , A summarization of turbulence and ionospheric

"wind" measurement theories with application of the latter to

preliminary data at 75 kc/s. Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF 19(604). 1304, Scientific Report No. 88, Aug. 1, 1956. 133 p. 37 figs. , 5 tables, 37

refs. , numerous eqs. --The initial problem presented in this

report is a study of the modern theories of turbulence and

their application. Besides the historical introduction, which

is the first section, the work is divided into three main parts.

The classical and statistical theories of turbulence are
315

discussed in the first two sections and their applications in

the third. The application of most interest here is the study

of ionospheric "wind" motions. This problem is gone into in

some detail with a summary of the experimental and analysis

work necessary for obtaining the desired information. The

main purpose for studying ionospheric "winds" is to achieve

an understanding of the dynamics of the ionosphere and provide information as to the daily variation of "winds". --Author's abstract.

A-1069 Sandoz, O. A. ; Stevens, E. E. and Warren, E. S. , Develop- ment of radio traffic frequency prediction techniques for use

at high latitudes. Institute of Radio Engineers, Proceedings,

47(5): 681 -688, May 1959. 5 figs. , 60 refs.

A-1070 Sao, Kazuo and Maeda, Tsuyako, Special daytime waveform

and the distance from its origin. Nagoya, Japan. Univ. Research Institute of Atmospherics, Proceedings, 3:110-112,

Nov. 1955. 4 figs., table. DWB--Data on some four dozen

sferics recorded at the Research Institute of Atmospherics

from June 17 to June 22, 1955 are tabulated. The sferics selected consist of a characteristic oscillation with two welldefined peaks. It is assumed that the first pulse corresponds

to the ground wave and the second to the doubly reflected sky

wave. Supposing the height of the reflecting D layer to be

65 km, the simple reflection theory is found to agree with the

observed wave forms. --G. T. A-1071 Sao, Kazuo and Shiga, Tamenari, Some considerations of the

waveform of atmospherics due to ionospheric reflection. Nagoya, Japan. Univ. Research Institute of Atmospherics, Proceedings, 3:47-53, Nov. 1955. 13 figs. , 2 tables, eq. DWB

--By assuming that the source of atmospherics is a single rec- tangular pulse, that the reflecting layer is a finite conductor

sharply bounded at a height of 80 km, and that the earth is a perfect conductor, the authors show by numerical computation

how a pulse is transformed into a rather smooth half-wave, and

how the calculated wave form is consistent with that observed

in practice. Ground wave and the earth's magnetism are neglected in order to simplify the calculations. --From authors'

abstract.

A-1072 Sao, Kazuo, Echo type waveforms which appear to exhibit

the effect of reflections from two layers in E region. Nagoya.

Univ. Research Institute of Atmospherics, Proceedings, 4:86-

89, Dec. 1956. 13 figs. DWB--Nice illustrations are presented for a special type of nighttime sferics wave form recorded

in June 1955 and March 1956. In each case, 2 distinct series

of peaks or pulses are discernible — each representing a
316

reflection between earth and ionosphere by a different mode

of 545 wave forms studied, 186 or 16% were of this type. It is concluded that peaks represent reflection from a height of

75 and 80 km (HORNER suggests 77 and 85 km). Distances

are also computed. --M. R.

A-1073 Sao, Kazuo, Researches in the frequency analyses of waveforms of atmospherics. Pt. 1 . Nagoya. Univ. Research Institute of Atmospherics, Proceedings, 5:12-30, March 1958. 8

figs. , 4 eqs. DWB--In order to illustrate the wave forms of

atmospherics with the knowledge of pulses radiated from the

origin and theories of propagation of VLF waves, investigations of the frequency spectra obtained with the aid of frequency analyses were proposed. In this field, F. W. CHAPMAN

and others observed the responses of a number of narrow -band

receivers tuned to various frequencies. The results were based on the smooth daytime type of atmospherics originated at

known distances up to about 4000 km. From these results

they reduced the frequency characteristics of attenuation factors of very long wave propagation. Smooth and general complicated type wave forms of sferics are analyzed. --From author's abstract.

A-1074 Sato, Teruo (Geoph. Inst. , Kyoto Univ. ), The reflection

coefficient of the long wave. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere in Japan,

7(2):89-70, 1953. DWB--In the case where the wave is re- flected at the boundary at any height (^) from the base of the

ionized region and the wave does not penetrate at all to the

height above (Z), the reflection coefficients for the wave of

16 kc/s are about 0. 62, 0. 36 and 0. 24 when the thicknesses of

the penetration region are 1, 2 and 3 km, respectively, in the

case of an ionic density of 3 X 10^ cc. In the case where the

wave penetrates to any height without limitation to the reflection point, the reflection coefficients for the wave of 16 kc/s

are about 0. 24, 0. 47 and 0. 77 when the gradients of the electron density with height are 102 cc, and 3 X 102 cc and 103

cc per 1. 5 km, respectively. --I. L. D.

A-1075 Satyanarayana, R. and Khastgir, S. R. (Banaras Hindu Univ.

Banaras), Polarization of down-coming wireless waves of med- ium wavelengths. Journal of Scientific and Industrial Research, Ser. B, 11(6):211-215, June 1952. 6 figs. , table, 3 refs.

DWB--Investigations at selected radio station in India showed

that: 1) only ordinary waves were received, 2) the polarization

was lefthanded and elliptical, at times turning into a straight

line or a circle and 3) the ratio of normal and abnormal component and the phase difference between these components

varied randomly with time--W. N.
317

A-1076 Satyanarayana, R. ; Bakhru, K. and Khastgir, S. R. (all,

Banaras Hindu Univ. , India), Triple-splitting of the F echoes. Journal of Atmospheric and Terrestrial Physics, London,

13(3/4): 201 -204, Feb. 1959. 2 figs. , 16 refs. DLC--An

account is given of the polarization studies made on the

triple F echoes, obtained by employing pulses of waves of

frequency, 3 Mc/s, at vertical incidence. The polarization

studies revealed that the first component after the ground

pulse was the normal extraordinary component having a righthanded sense of rotation, the second component was the nor- mal ordinary component having a left-handed sense of rotation and the third component was the Z-component having a left-handed sense of rotation. In addition to the coupling

process suggested by ECKERSLEY and RYDBECK between

the ordinary and extraordinary waves, and operative only in

high geomagnetic latitudes, the partial reflection and transmission at the level of ionospheric reflection for the ordinary

component have been considered as a plausible process for

getting the Z-component. Since the coupling process is not

likely to produce a detectable Z-component at low geomagnetic latitudes the occasional presence of the Z-component at

low latitudes has been attributed to the partial reflection and

transmission process which may take place at all latitudes.

The view that the Z-component really corresponds to the left

handed ordinary component suffering reflection at the level

2 2 corresponding to p - p +

Authors' abstract. ° p . Ptt has been supported.

A-1077 Saxton, J. A. , Ionospheric scattering at V.H. F. Mechanism

of propagation: practical application to long-range communication. Wireless World, London, 62(1): 36-40, Jan. 1956. 4

figs. DLC--Scattering by irregularities of refractive index is

described. Turbulence causes scattering in the troposphere

which is chiefly effective in 500-5000 Mc/s. Transmission

up to 2000 km on 25-60 Mc/s may be due to forward scattering by ionic clouds in the E region or to reflection from ionized meteor trails or both. The characteristics of such signals and their use in communication are discussed. --C. E. P. B.

A-1078 Saxton, J. A. (D. S. I. R. , Slough, Gt. Brit. ), La physigue

de la diffusion ionospherigue sur ondes metrigues. (Physics

of ionospheric scattering of meter waves. ) L'Onde Electrique,

Paris, 37(362) :450-455, May 1957. 20 refs. , 2 eqs. DLC--

Possibilities of VHF communication (25-60 MHz) over distances of the order of 1000-2000 km by means of irregularities

in the ionospheric E region have been established by recent

research. The author reviews theoretical and experimental re- search work concerning the mode of propagation and concludes

that the scatter signals may be due to either turbulence or
318

meteors. While it is not possible, at present, to ascertain

the prevalence of either oi these factors, it appears probable

that night signals are almost entirely due to meteoric scattering. --G. T.

A-1079 Saxton, J. A. , Long-distance radio propagation above 30

Mc/s. Nature, London, 181(4617): 1184-1187, April 26, 1958.

DWB--The London Institution of Electrical Engineers held a symposium on Jan. 28, 1958 at which more than 20 papers

dealing with British contributions to the study of long-distance radio wave propagation at frequencies above 30 Mc/s

were presented. Two developments so far recognized in Britain are: the possibility of long distance communication between 1, 000 and 2, 000 km on frequencies exceeding the maximum usable frequency and that transmission occurs via the

E region of the ionosphere and also through the troposphere.

Brief precis of some of the papers presented at the symposium

are included. --N. N.

A-1080 Schenk, Karl, Die Funkausbreitung als neues Hilfsmittel in

der modernen Wetterforschung. (Radio propagation as a new

aid in modern weather observation. ) Deutscher Wetterdienst

in der US-zone, Berichte, No. 12:215-218, 1950. Discussion

by H. Israel and Heinz Meinhold (with 3 figs. ) p. 218-220.

MH-BH--Argues that broadcast reception offers a means of investigating the relation between the ionosphere and weather

and a possibility of constructing charts of levels in ionosphere. Proposes term "Funkmeteorologie" (Radio meteorology).

--C.E. P.B.

A-1081 Schilling, G. F. and Sterne, T. E. (both, Astrophysical Obs.,

Smithsonian Inst. ), Preliminary orbit information for USSR

satellites Alpha one and Alpha two. Smithsonian Institution.

Astrophysical Observatory, IGY Project No. 30. 10, Special

Report, No. 1, Oct. 14, 1957; re-issued: Dec. 2, 1957. 20

p. tables. Also issued in "edited form" as Smithsonian Contributions to Astrophysics, Wash., D. C, 2(10):191-198,

1958. DWB, DLC--This is the first report on notification, re- ception, tracking, bulletins on reception, and predicted tracks

of the first Soviet Sputnik launched Oct. 4, 1957. The orbit

inclination was 65 , periodicity 95 m; weight 83. 6 kg, diameter 58 cm, output 1 watt, high frequency 40. 002 Mc, low frequency 20. 005 Mc. First reception of radio signals at NRL

in Washington, D. C. was at 20.45 EDT, Oct. 4. --M. R.

A-1082 Schindelhauer, F. , Peilung der Ausgleichsvorgange, die Luft - storungen verursachen. (Bearings of discharge phenomena giving rise to sferics. ) Hochfrequenztechnik und Elektroakustik,

Berlin, 54(5):109-111, Oct. 1939. DLC--
319

Observations of sferics at Potsdam Observatory in July to Oct.

1938 are discussed. The results, presented in curves, show

long wave sferics of E-W direction in the morning, turning

more to N-S at midday. The short wave sferics generally came

from N-S, otherwise following the diurnal variation as for long

wave sferics. Sferics originate in the ionosphere, the ionospheric currents give rise to the E-W direction. Sferics may

also be produced by thunderstorms. --W. N.

A-1083 Schindelhauer, F. and Lauter, E. A. , Ein Beitrag zur Erforschung der Vorgange bei Mogel-Pellinger-Effekten. (A contribution to the observation of the processes in Mogel-Dellinger

effects. ) Zeitschrift fur Meteorologie, 4(7-8): 243-245, JulyAug. 1950. 2 figs., 5 refs. MH-BH--On Sept. 13, 1949,

13. 02 h, strong short wave fading at many stations coincided

with a magnetic eruption effect. This was followed at 3-minute intervals by a weak increase in reception on 1250 m, increased disturbance on 2450 and 11, 000 m. The frequency

necessary to penetrate D layer at Dakar rose to 15. 3 MHz.

Other observations were made on June 28, 1949. Causes

briefly discussed. --C. E. P. B.

A-1084 Schlapp, D. M. (Cavendish Lab. , Cambridge), Some measurements of collision frequency in the E region of the ionosphere. Journal of Atmospheric and Terrestrial Physics, N. Y.

,

16(3/4): 340-343, Nov. 1959. fig., 9 refs. , eq. DWB, DLC

--Measurements of collision frequency in the E region were

made by observing how the deviative absorption of a radio

echo varied with its group path as a critical frequency was

approached. The collision frequency at heights between 105

km and 120 km was found to vary with a scale height of about

16 km. In 1955. the collision frequency passed through a value of 2 X 10^ sec"l at a height of about 112 km. There is

some evidence that, when the sunspot number is greater, the

collision frequency at a fixed height is greater. --Author's abstract.

A-1085 Schmelovsky, Karl-Heinz, Probleme der Ausbreitung in tropos - pha'rischen und ionospharischen Wellenleitern. (Problems of

the propagation of tropospheric and ionospheric wave guides. ) Germany. Deutsche Demokratische Republik. Meteorologischer und Hydrologischer Dienst, Abhandlungen, 7(49): 1-24,

1958. 14 figs. , 2 tables, 23 refs. , numerous eqs. DLC--

An attempt is made to find a general procedure for determining the propagation characteristic of a wave guide, in particular its propagation damping. In the derivation of these characteristics the author constructs a model which describes the

field in the wave conductor as a process of interference of

waves which are reflected at the limits. By using this model
320

it is possible to retain the concept of the reflection factors.

The problems considered include exclusively wave guides

having a propagation constant that is very complex as a re- sult of radiation or reflection losses, thereby the boundary

wave length looses its fundamental importance; approximately

spherical symmetrical guides are present; the ratio of longitudinal to transverse measurements is usually substantially smaller than in the case of artificial hollow guides. The mathematical treatment of the propagation in the case of homogeneous

wave guides, in tropospheric wave guides and in homogeneous

wave guides are presented and application and illustrations

for the interpretation of sunrise effects in the atmospheric

noise level, in the longest wave lengths and propagation constants of tropospheric wave guides are given. --I. L. D.

A-1086 Schmelzer, R. J, , Total atmospheric absorption of 60 kmc

radiation. Lockeed Missile Systems Division, (Pub. ) LMSD2793, Sept. 19, 1958.

A-1087 Schmerling, E. R. (Ionosphere Res. Lab. , Penn. State Univ. ), An easily applied method for the reduction of h-f records to

N-h profiles including the effects of the earth's magnetic field . Journal of Atmospheric and Terrestrial Physics, London, 12(1):

8-16, 1958. 7 figs. , 2 tables, 10 refs. , 13 eqs. DLC-A

method is presented by means of which experimental h'-f re- cords may be readily reduced to electron density height profiles without the use of computing aids during the final reduction process. No special assumptions are made concerning

profile shapes, account is taken of the earth's magnetic field,

and collisions are neglected. This method depends on sampling h* at fixed sub-multiples of the frequencies f at which

true heights are required; true heights being then simply obtained by averaging these values. The sampling frequencies

depend on the parameters of the earth's magnetic field, and

must be computed for the magnetic coordinates of each station

from which records are to be analyzed. This computation, in

its entirety, is quite complex; but once performed, the results

are available for use on any number of records. The method

is, therefore, especially suitable for the rapid routine reduction of large numbers of records. Complete computations are presented for one station, and the results are checked against

an analysis of h'f curves for known profiles. --Author's abstract.

A-1088 Schonland, B. F. J. ; Elder, J. S. and van Wyk, J. W. , Reflec - tion of atmospherics from the ionosphere. Nature, London,

143(3630) :893-894, May 27, 1939. fig., 4 refs. DLC--The

analysis of thousands of sferics oscillograms that travelled

from 50 to 2800 km supports the Australian findings that the

structure of the wave form arises from repeated reflections.
321

Evidence for the existence of a real lowering of the effective

height of reflection was found. The sferics discussed were

all due to flashes to ground. --W. N.

A-1089 Schrag, R. L. (Penna. St. Coll. , Radio Propag. Lab. ), An

investigation of the 150 Kc/s propagation characteristics of

the upper ionosphere. Pennsylvania. State College. Ionosphere Research Laboratory, Contract AF 19(122)-44, Ionospheric Research, Scientific Report, No. 33, March 15, 1952.

41 p. graphs, 10 refs. , 48 eqs. DWB--Extended studies of

the 150 Kc/s propagation characteristics into and through the

F region indicate that the small amount of the ordinary wave

component passing through the E layer, where the total reflection takes place below the maximum of electron density of

this layer, will be totally absorbed in the F region. The ex- traordinary component, however, suffers but moderate absorption and no reflection in the E layer, hence its possible use

for radio sounding of the upper ionosphere or Stunner ring is

the premise of the detailed investigation. The discussion emphasizes the following topics: 1) a complete wave solution

carried through a found "pole" at 939 km with the aid of 2) a new method for solving the uncoupled wave equation, heretofore not obtained. --W. N.

A-1090 Schrag, R. L. , Extended range ionospheric observations at

150 Kc/s . Pennsylvania. State Univ. Ionosphere Research

Laboratory, Contract AF 19(122) -44, Scientific Report No. 66,

July 15, 1954. 137 p. 49 figs. , 7 tables, 16 refs. MH-BH--

Results of low frequency pulsed radio sounding experiments

employing extended-range receiving instrumentation are discussed. The experiments were conducted with 150 Kc/s vertically incident waves, and involved amplitude and polarization studies of multiple-hop echo systems. Nighttime observations have revealed two phenomena of interest: (1) Multiplehop amplitude decay patterns for normal E-region echoes during low absorption conditions indicate a nearly continual

roughness of the reflecting surface. On occasion these patterns exhibit pronounced focusing, indicating that ionospheric

reflections are taking place from concave "surfaces. " Effects

of such large scale irregularities in the surfaces of constant

N are not visible in first-hop echo observations. The focusing results are summarized, and estimates are presented concerning the nature and sizes of the E-region irregularities involved. (2) Occasionally, trains of weak echoes are detected

having, principally, extraordinary polarization and very low

successive-hop attenuation. Their emplitudes and delays are found to be consistent with a highly efficient M-type reflection mechanism utilizing reflecting boundaries at approximately 130 and 240 km. The lower boundary, being partially
322

transparent, is interpreted as a sporadic E ionization slab;

while the upper reflector is believed to result from a deep ionization "well" between Regions E and F. It is concluded that

the nighttime electron density at 240 km may, on occasion,

fall to a value less than 312 elec/cc. --Author's abstract.

A-1091 Schrott, R. , Ein Echolotungsaerat fflr Ionospharen-und Wetterforschung. (An echo-sounding apparatus for ionosphere and

weather investigation. ) Archiv fur Meteorologie, Geophysik

und Bioklimatologie, Ser. A, 3(1-2):109-112, 1950. 3 figs. , 3 refs. German, English and French summaries p. 109. DWB--

An impulse transmitter and receiver is described combining

low cost, high accuracy and safe working. Wiring diagrams

given. It can be used for measuring critical frequencies and

the altitude of the ionosphere. --C. E. P. B.

// A-1092 Schumann, Winfried Otto, Uber die Dampfunq der elektromagnetischen Eigenschwingungen des Systems Erde-Luft-Ionosphara

(On the damping of the natural electromagnetic oscillations of

the system earth-air-ionosphere. ) Zeitschrift fur Naturforschung, 7a(3-4): 250-252, March-April 1952. eqs. DLC--A

theoretical equation for the damping of the lowest frequencies

is developed, which should permit the calculation of the effective height of the atmosphere and the effective conductivity

of the ionosphere by emitting short impulses. --C. E. P. B.

A-1093 Schumann, Winfried Otto (Elektrophysikalisches Inst. T. H.

Munich), Uber die Ausbreitung lanqer elektrischer Wellen um

die Erde und einiqe Anwendungen auf Senderinterferenzen und

Blitzsignale. (Propagation of long electric waves round the

earth and some applications to transmitter interferences and

lightning signals. ) Zeitschrift Mr Angewandte Physik, Berlin,

6(8):346-352, 1954. figs., 22 refs. , eqs. DLC -Interferences

of long wave transmitters, atmospheric processes, lightning

discharges, sferics and reflected impulses are first discussed.

Conditions for long wave propagation are well-known but the

problem of propagation of electric waves in the atmosphere is

still not well understood. On the one hand, it is necessary

to study the very small conductivity of the ionosphere during

signals of the "slow tail" type in order to understand the important fading, while signals consisting of a long series of

reflected impulses require especially good reflection properties, i. e. , high conductivity of the ionosphere and different

reflection heights. The kind of wave types which is received

meteorologically is to a large extent still unknown and should

be analyzed in detail. --A. M. P.
323

A-1094 Schumann, Winfried Otto, Uber die Oberfelder bei der Ausbreitung langer elektrischer Wellen im System Erde-Luft-Ionospha're und 2 Anwendungen (horizontaler und senkrechter Dipol).

(On "modes" in the propagation of long electric waves in the

earth-air-ionosphere system and two applications (horizontal

and vertical dipole). ) Zeitschrift fur Angewandte Physik, Berlin, 6(l):35-43, 1954. 2 figs. , 14 refs. , 39 eqs. DLC--It

is shown that the earth's curvature may be disregarded when

determining "modes" of electric waves in the kilometer range,

thereby replacing radial Bessel functions by exponential distributions. Propagation properties and emission intensities

of such modes are determined for the electrical and magnetic

vertical dipoles according to the method of singular characteristic functions. The propagation of thunderstorm sferics is

also discussed. --Trans, of author's abstract.

// A-1095 Schumann, W. O. , Uber die Beeinflussung der Ausbreitung

sehr langer elektrischer Wellen duroh das Magnetfeld der

Erde. (Influencing of propagation of very long electric waves

by the geomagnetic field. ) Naturwissenschaften, 42(4):91-

92, Feb. 1955. 2 refs. DWB--Under the influence of a vertical magnetic field the ionosphere becomes an anisotropic conductor and a wave of very low frequency splits into two coupled waves. This effect and its avoidance are discussed. -- C. E. P. B.

A-1096 Schwentek, Heinrich, Bestimmung eines Kennwertes fur die

Absorption der Ionosphare aus einer automatisch-statistischen

Analyse von Feldstarkeregistrierungen. (Determination of

ionospheric absorption coefficient by means of automatic statistical analysis of field strength recordings. ) Archiv der Elektrischen Ubertragung, Stuttgart, 12(7):301-308, July 1958. 11

figs. , 15 refs. , 14 eqs. DLC--A simple method is described

by which the nondeviative absorption of the ionosphere can be

determined continuously by field strength measurements at oblique incidence. The conditions of a suitable transmission

path are discussed. An analysis of the field strength frequency distribution measured by a statistical counter renders

possible the separation of the main transmission paths from

each other. Thus absorption values for hourly intervals can

be determined immediately. For this purpose the absorption

values are reduced to vertical incidence. Furthermore the

state of the ionosphere may be derived from the distributions.

Thus the mean reflection coefficient of the Es layer at night as well as its frequency are immediately obtained. For the delayed diurnal variation of absorption dependent on the sun's

zenith angle a simple formula is suggested. --Author's abstract.
324

A-1097 Scott, James C. W. , Longitudinal and transverse propagation

in Canada. Journal of Geophysical Research, 55(l):65-84f March 1950. 13 figs. , table, 8 refs. , eqs. MH-BH--Multifrequency pulse measurements north of auroral zone in Canada

show that the ionosphere is very turbulent and unstable. The

echoes are peculiar and longitudinal. The causes are discussed. The apparent magnetic field is calculated; it shows

large diurnal and seasonal variation. --C. E. P. B.

A-1098 Scott, James C. W. , The ovro-freguency in the Arctic E layer. Journal of Geophysical Research 56(1):1-16, March 1951. 7

figs., 4 tables, 8 refs., 15 eqs. DWB--Calculation of the

gyro-frequency in the E layer at Canadian Arctic ionospheric

recording stations gives a lower magnetic field than that obtained by extrapolation of the terrestrial field measured at

ground level, and at one station (Resolute Bay) a large semidiurnal variation with maxima at 06 and 18 hr local time. Ray

path deflections which can explain similar effects previously

reported for the F layer cannot be responsible in the E layer

because of the opposite sense of this deviation and because

of the small layer-thickness. Moreover, no semi-diurnal var- iation was found in the F layer. It is shown that these new

W layer phenomena may be due to a variable concentration of

heavy ions rising to over 4000 times the density of free electrons. --From author's abstract.

A-1099 Scott, James C. W. (Defence Res. Telecom. Establ., Defence Res. Board, Ottawa), Real and complex wave polariza - tion in the ionosphere . Journal of Geophysical Research, 58

(4):437-443, Dec. 1953. 3 figs. , table, 4 refs. , 13 eqs.

DLC--The relation between the polarization ellipse in the wave

front and the complex polarization at vertical incidence in a slowly-varying horizontally-stratified ionosphere is reviewed.

Charts and a table are given showing the sense, orientation

and eccentricity of the polarization ellipse under all conditions of plasma frequency, collisional frequency, wave frequency, and magnetic field intensity and direction. --Author's

abstract.

A-1100 Scott, J. R. , Wind statistics at Singapore. Royal Meteorological Society, Quarterly Journal, 83(357): 381-383, July 1957.

table, 4 refs. DWB--Weekly radar ascents at Singapore, increasing to daily, from July 1950 to Dec. 1955 are tabulated

by seasons 5000 - 70, 000 ft. Up to 30, 000 ft cr (standard

vector deviation) varies little. From 30, 000 - 50, 000 ft crp = constant. --C. E. P. B.
325

A-1101 Sechrist, C. F. , Jr. , Theory and design of a traveling wave

antenna system for long wave sweep freguency investigation

of the ionosphere at vertical incidence. Pennsylvania. State

Univ. Ionosphere Research Lab. , Contract AF 19(604) -1304,

Scientific Report, No. 91, March 1, 1957. 49 p. 16 figs.

,

8 refs. , eqs. DWB (M10. 535 P4151) --The analysis, design,

and evaluation of the new combination 75 Kc/s folded dipole

antenna, 225 kc/s antenna, and long wave sweep frequency

transmitting antenna system being erected at the Scotia Field

Station are discussed. The system to be used for long wave

sweep experiments consists of a 6500' long off-center fed

transmission line antenna for frequencies between 50 and 220

kc/s and a 2000' long center fed transmission line antenna

for frequencies up to 800 kc/s. Taking into account ionospheric absorption and atmospheric noise levels for summer

and winter days and nights, a comparison of required field

intensity to overcome atmospheric noise and expected incident field intensity with the transmission line antenna is made

for the frequency range 50-1000 kc/s. --Author's abstract.

A-1102 Sechrist, C. F. , Jr. , Instrumentation for long wave sweep

freguency investigation of the ionosphere at vertical incidence.

Pennsylvania. State Univ. Ionosphere Research Lab. Contract AF 19(604) -3875, Scientific Report No. 103, June 1,

1958. 96 p. 67 figs. , 10 refs. DWB (M10. 535 P415i)--The

description and operation of the instrumentation for long wave

sweep frequency investigation of the ionosphere is covered in

this report. The beat frequency method of generating wide

frequency sweeps is used in the 0. 5 megawatt transmitter

which covers the frequency range from 50 to 1, 000 kc/s.

Transformer coupled, push-pull, wide-band amplifiers are employed in the transmitter providing class B operation with good

waveform, and obviating the need for complex tuning arrangements. The transmitting antenna used for sweep operation is a 60 Kc/s folded dipole that is converted to a balanced transmission line antenna by an automatic switching arrangement.

An automatic control system is described which permits unattended, alternate operation of the 60 Kc/s and long wave

sweep transmitters. A sample h'-f record, obtained with the

sweep equipment, appears near the end of the report. Recommendations for future development conclude the report, and the

appendices cover the design procedures. --Author's abstract.

A-1103 Sechrist, C. F. , Jr. , Preliminary theory and interpretation of

long wave sweep freguency records. Pennsylvania. State Univ.

Ionosphere Research Lab. , Contract AF 19(604) -3875, Scientific Report, No. 115, Feb. 1, 1959. 98 p. 44 figs. , 35 refs.

,

eqs. DWB (M10. 535 P415i)--This report being the first of

several planned on low frequency ionograms as obtained at the

laboratory summarizes the NBS work on low frequency results,
326

the theoretical work and results obtained at the laboratory including qualitative interpretation of some low frequency ionograms. The results as obtained for the stable night Aug. 10-

11, 1958 are discussed and the disturbed ones June 9-10,

1958 accompanied by samples of h^- - P records. Results for

the stable night showed echoes varying from 100 km at 140

bc/s to 110 km at 1 Mc/s. The approximate 500 kc/s main

echo polarization when computed showed up eliptically. Results for the disturbed nights are itemized and in general

future existence of different sporadic E layers at differing

heights. The normal E layer ionization was decaying. --W. N.

A-1104 Seddon, J. Carl (U. S. Naval Res. Lab. , Wash. , D. C. ), Propagation measurements in the ionosphere with the aid of

rockets. Journal of Geophysical Research, Wash. , D. C.

,

58(3): 323-335, Sept. 1953. 10 figs. , 7 refs. , 11 eqs. DWB--

Daytime measurements of electron density, ion density, electron collision frequency, and earth's magnetic field in the

ionosphere were made during V-2 rocket flights at the White

Sands Proving Ground, New Mexico. Two CW harmonically

related frequencies were radiated from the rocket to two ground

stations to obtain measurements of the ordinary and extraordinary indices of refraction in the region around the rocket. The

results for one flight show an ion layer with a maximum of

5 X 10° ions/cc and a small electron layer with a maximum of

7500 el/cc just below the E 1 layer. On a Sept. day the F

1

layer remained dense up to the E2 layer, while on a Jan. day

the density apparently decreased above the Fl layer maximum

to much lower values. It is shown that the Lorentz polarization term should not be used in the E layer at 4 Mc. --Author's

abstract.

A-1105 Seddon, J. C. ; Pickar, A. D. and Jackson, J. E. (U. S.

Naval Research Lab. , Wash. , D. C. ), Continuous electron

density measurements up to 200 km. Journal of Geophysical

Research, 59(4): 513-524, Dec. 1954. 9 figs. , 11 refs. , 6

eqs. MH-BH--Measurements in the ionosphere using the Seddon propagation technique were conducted with the Viking 10

rocket, launched at 10:00 a. m. MST on May 7, 1954, at the

White Sands Proving Ground, New Mexico. This rocket reached a record altitude of 219 km, and provided very good data

for both upward and downward trajectories. Ordinary and ex- traordinary indices of refraction at 7. 754 Mc were measured

in the region surrounding the rocket. From these indices, it was possible to determine accurately the electron distribution

from 84 to 200 km. By using the P'-f records taken during the

rocket flight, the electron density curve was extrapolated up

to the maximum of the F2 region (2. 9 x 10^ el/cc at 288 km).

The measurements showed a rapid increase in density from
327

1 X 104 el/cc at 91 km to 1 X 10$ el/cc at 101 km. This was

followed by additional but less rapid increases up to the peak

of the Fl region (2. 1 X 10$ el/cc at 170 km). Densities in

the 170- to 200-km region were, in general, five to ten percent

lower than the Fl maximum density. Although obtained during a period of low sunspot activity, these latest results agree

remarkably well with previous results reported by Seddon and

Jackson for periods near the sunspot maximum. In all cases,

the daytime ionosphere was seen to remain dense throughout

the E region and up to the F 1 region, with only occasional

minor peaks in density. In all cases, the distribution obtained agreed very closely with the P'-f records. Sporadic echoes

are apparently due to partial reflections from high gradient re- gions. --Author's abstract.

A-1106 Seddon, J. Carl (U. S. Naval Res. Lab., Washington, D. C. ), Electron densities in the ionosphere. Journal of Geophysical

Research, 59(4):463-466, Dec. 1954. 4 figs. DWB--Recently the author published a curve of electron densities obtained

from rocket experiments. The published curve showed a sharp

decrease in electron density at 145 km. Another interpretation of the data eliminates this decrease. The new interpretation is based on a breakdown in independence of propagation

of the magneto-ionic components of a CW-signal transmitted

from the flying rocket. --From author's abstract.

A-1107 Seddon, J. Carl, Rocket investigations of the ionosphere by

radio propagation method. U. S. Naval Research Laboratory,

Upper Atmosphere Research Report, No. 22; NRL Report 4304,

March 1, 1954. 37 p. figs. , tables, 9 refs. , eqs. DWB--

Daytime measurements of electron density, ion density, electron collision frequency, mean molecular cross section, and

earth's magnetic field during V-2 rocket flights at the White

Sands Proving Ground, New Mexico, were obtained on March

7, 1947, Jan. 22, 1948, and Sept. 29, 1949. In each case a

4. 274-Mc signal and its 6th harmonic were radiated from the

rocket to receiving stations on the ground to obtain measurements of the ordinary and extraordinary indices of refraction

of the region around the rocket. The results of one flight show

an ion layer with a maximum of 5 X 10^ ions/cc and a small

electron layer with a maximum of 7500 el/cc just below the Ellayer. On a September day the El layer remained dense up to

the E2 layer, while on a January day the density apparently

decreased above the El layer maximum to much lower values.

It is shown that the Lorentz polarization term should not be

used in E layer computations at 4 Mc. A detailed explanation

of the data analysis methods is included in the appendixes.

Extensive calculations using the general Appleton-Hartree formula have been made at 4. 274 Mc and some of the results are
328

shown for various collision frequencies, using the value of

the magnetic field at 100 km above the White Sands Proving

Ground, New Mexico. —Author's abstract.

A-1108 Seddon, J. C. and Jackson, J. E. (both. Naval Research Lab.,

Wash. , D. C. ), Absence of bifurcation in the E layer . Physical Review, N. Y. , 97(4): 1182-1183, Feb. 15, 1955. fig. , 8 refs. Also: Pfister, W. ; Ulwick, J. C. and Marcou, R. J.,

Further remarks on bifurcation in the E layer . Ibid. , p. 1183-

1184. 3 refs. DLC--In the first article electron density distribution curves are given covering the altitude range 90-150

km as obtained from three separate New Mexico rocket flights

spaced over 5 years. Reasons are given for placing considerable confidence in the results. All fail to show any bifurcation in the day-time E layer, in contradiction of the results of

Lien - Marcou et al. The second article, a reply to Seddon

and Jackson, points out that the results of both groups of workers are consistent within themselves but depend on different

analyses — Seddon's experiments are based on the change in

phase delay, while the authors' give the group delay. It is

pointed out that the magnetic field has an important effect on

the ray paths and adequate allowance for this may affect the

results of both experiments.

A-1109 Seddon, J. C. and Jackson, J. E. (both, U. S. Naval Research

Lab. , Wash. , D. C. ), L 'application des fusees a 1 'etude de

I 'ionosphere. (Application of rockets to the study of the ionosphere. ) Annales de Geophysique, Paris, 11(2): 169-172,

April/June 1955. 2 figs. , 7 refs. , eqs. DLC--Doppler measurements from rockets to determine electron density as a function of altitudes to 160 and 300 km. respectively, are shown

graphically in two figures. Density was obtained by direct

measurement to 200 km and by extrapolation using ionograms

up to 300 km. --M.R.

A-1110 Seddon, J. Carl (Rocket Sonde Branch, U. S. Naval Res. Lab. ), High electron density gradients in the ionosphere as observed

with rockets. AGARDograph, Paris, No. 34:171-181, Sept.

1958. 5 figs. , 2 tables, 7 refs. DWB (629. 1323 N864a)»

Many daytime measurements of electron density profiles with

rockets have been made during the condition known as "sporadic E". In all cases, it was found to be a high electron density

gradient region covering in general a radius in excess of 50 km.

Gradients as large as 10^ el/cc per km have been observed.

Various characteristics of sporadic E, such as horizontal variability, thickness, and maximum electron densities are briefly

discussed. Evidence of many other large electron density gradients between 66 and 200 km is presented. One such gradient

is always found to be present near the mesopause. The others
329

are variable in occurrence and altitude, except for a strong

tendency for E region gradients to occur at particular altitudes

separated by about one scale height. One night flight at Fort

Churchill, Manitoba, Canada is discussed where two sporadic

E regions existed. One of these, at 98 km, had a characteristic never before observed, of the large gradient being on top

side. Evidence is presented that shows that a spread F-condition existed above 190 km and that it probably consisted of

many irregular, turbulent high-gradient regions. --Author's abstract.

A-llll Seddon, J. Carl (U. S. Naval Res. Lab., Wash., D. C),

Differential absorption in the D and lower E regions . Journal

of Geophysical Research, Wash., D. C. , 63(1):209-216,

March 1958. 6 figs. , 5 refs. , 6 eqs. DLC.

A-1112 Seddon, J. C. and Jackson, J. E. (both, U. S. Naval Res.

Lab. ), Rocket Arctic ionospheric measurements. International Geophysical Year, 1957/1958. IGY World Data Center A,

IGY Rocket Report Series, No. 1:140-148, July 30, 1958. 7

figs., 6 refs., 2 eqs. DWB (M07. 362 H237ex).

A-1113 Seddon, J. C. and Jackson, J. E. (both, U. S. Naval Res.

Lab. ), Ionosphere electron densities and differential absorption. International Geophysical Year, 1957/1958. IGY World

Data Center A, IGY Rocket Report Series, No. 1:149-158, July

30, 1958. 11 figs., 8 refs. , eq. DWB (M07. 362 H237ex).

A-1114 Seddon, J. C. and Jackson, J. E. , Rocket studies of the Arctic ionosphere. IGY Bulletin, Wash., D. C, 20:7-9, 1959.

American Geophysical Union, Transactions, 40(l):63-65, March

1959. DWB.

A-1115 Seddon, J. C. (Nat. Aeronautics and Space Admin. ), Rocket

observations of high electron density gradients in the ionosphere. American Geophysical Union, Transactions, 41(1): 113-

118, March 1960. 4 figs. , 2 tables. DWB, DLC.

A-1116 Sethuraman, R. (Physical Res. Lab. , Ahmedabad), Rates of

fading of reflected pulses of vertically incident electromagnetic waves at Ahmedabad on 2. 6 and 4. Mc/s. Journal of Scientific and Industrial Research, New Delhi, Sec. A, 17(12);

Special Supplement, Dec. 1958. p. 50-53. 4 figs. , table,

7 refs. DWB, DLC --Summarized results of the Physical Research Laboratory's observations at Ahmedabad Oct. 1956 - March 1953 show that: (1) rapid fading < 5 sec. period occurs

mainly during night hour and is somewhat dependent on magnetic activity; (2) low values of CR

is generally associated with

more rapid fading, and the F2 reflections exhibited a marked
330

correlation with the amount of spread of the pi -f records; (3)

nighttime F2 is sensitive to magnetic activities which daytime

E layer is not. --W. N.

A-1117 Shain, C. A. and Kerr, F. J. , A note on factors affecting the

interpretation of observations of transient echoes from the ion- osphere. Journal of Atmospheric and Terrestrial Physics, 6

(5):280-281, May 1955. fig., 6 refs. DWB-Observed shortlived echoes on 100 kw 18. 3 Mc/s radar direction vertically

showed maxima at 5 h and 10 h. The maximum at 5 h is due

to sporadic meteors. The maximum at 10 h is attributed to the

low cosmic noise at this time; when observations are corrected

for this the maximum disappears. --C. £. P. B.

A-1118 Shammatt, F. H. , Atmospheric whistlers and the electron density in the ionosphere . Texas. Univ. Electrical Engineering

Research Lab. , Contract AF 19(604) -5504, Report 6-30, Oct.

21, 1959. 22 p. 6 figs. , table, 10 refs. , 25 eqs. DWB

(M94. 7 T355r)--Some of the electromagnetic energy released

from lightning strokes travels a path through the ionosphere

essentially parallel to the magnetic lines of the earth's magnetic field. It arrives at the ground in the opposite hemisphere as a frequency dispersed wave train with time delay increasing with decreasing frequency. The extent of this dispersion has previously been shown to be a function of the height

distribution of electron density in the ionosphere along the

path traveled. This report presents a method of computing the

dispersion from a knowledge of the electron density and compares observed and computed dispersions based on an assumed

exponential electron density height distribution. The correlation between the two sets of curves is sufficiently good to lend

credance to the assumed electron distribution. This research

was carried out as one phase of a general propagation study

designed to investigate various tropospheric and ionospheric

refractive index distribution models. --Author's abstract.

A-1119 Shapley, A. H., On forecasting propagation disturbances to

radio communications in Alaska. Alaskan Science Conference,

2nd, Mt. McKinley National Park, Sept. 4-8, 1951, Proceedings, p. 281-282, pub. (1953?) DWB«Advance warning of

radio communication conditions in the North Pacific and Alaska

is being attempted by North Pacific Warning Service by the National Bureau of Standards Field Station at Anchorage, Alaska.

Variations in radio propagation are closely associated with abnormal conditions in the ionosphere. Studies of absorption,

Es movements, turbulence, fading, etc. are being undertaken.

--M.R.
331

A-1120 Shapley, A. H. , Comite des Sondaqes Ionospheriques.

(Committee of Ionospheric Soundings. ) International Scientific Radio Union, Bulletin d'Information, No. 112:14-15, how./

Dec. 1958. DLC --Program of the future activities of the Committee for ionospheric soundings and projects for improvement

of the organization. --A. V.

A-1121 Sharma, S. K. (Radio Communication Lab. Eng. Coll. Banaras

Hindu Univ. ), Effect of thermal expansion of the F2 region of

the ionosphere on the absorption of high frequency radio waves . Journal of Scientific & Industrial Research, Sec. A, 18(1): 17-

20, Jan. 1959. fig., 2 tables, 9 refs. , 5 eqs. DWB, DLC--

The total absorption of radio waves in the ionosphere has been

measured by the pulse technique at vertical incidence at different hours of the day. It has been found that for frequencies

below the critical frequency of Fl layer, only one maximum of

total absorption is generally observed while at frequencies

sufficiently above the critical frequency of the Fl layer, two

maxima, one before and the other after the local noon, are observed. The maximum observed before noon has been attributed to the thermal expansion of the F2 region of the ionosphere under adiabatic equilibrium, the effect of which is more

pronounced in the lower latitude. --Author's abstract.

A-1122 Shearman, E. D. R. , St udy of ionospheric propagation by

means of ground back-scatter. Institution of Electrical Engineers, London, Proceedings, Pt. B, 103(8) :203-209, March

1956. 6 figs. , 12 refs. DLC. Also his: The technique of

ionospheric investigation using ground back-scatter . Ibid.,

p. 210-223. 16 figs. , 27 refs. , 14 eqs. DLC. Also: Laver,

F. J.M. and Stanesby, H. , Experimental test of reciprocal

transmission over two long-distance high-frequency radio circuits. Ibid., p. 227-232. 6 figs. , 9 refs. , 3 eqs. DLC.

Also: Meadows, R. W. , Experiment to test the reciprocal

radio transmission conditions over an ionospheric path of 740

Km. Ibid. , p. 224-226. 6 refs. discussion on all papers,

p. 232-235. DLC --This series of papers and the discussion

on p. 232-235 covers many phases of a systematic program

conducted during 1949-55 in the British Isles to obtain data on

the back-scatter, skip distance, ionospheric layers involved

and height thereof for one to four hops (up to 11, 000 mi) propagation. It was found that better results were obtained in

winter than in summer, that the distances were shorter than

calculated, and that only about 1% of the cases showed distinctly different reception in one direction than in another.

Also the main proportion of energy is scatter back by the ground,

rather than by the ionosphere as many authors theorized. In

summer the energy is distributed over a considerable time with

several peak bands corresponding with reflection from several
332

ionospheric layers. In winter only 1 major band (return time)

is noted — that for F layer. The vertical incidence pulses do

not give exactly the same calculated height and skip distance

as the oblique pulse signals. Perhaps returns come from outside or in the edge of the calculated beam. --M. R.

A-1123 Shearman, S. D. R. and Harwood, J. (both, Radio Res. Stat.

Slough, Bucks, England), Sporadic E as observed by backscatter techniques in the United Kingdom. AGARDograph,

Paris, No. 34:111-128, Sept. 1958. 10 figs. , 4 refs. DWB

(32S-1323 N864a) --Observation of sporadic E clouds with a rotating-aerial backscatter sounder enables a greater sample

of Es clouds to be studied than the use of a vertical incidence

sounder, and permits the size, location and movement of

clouds to be estimated. Limitations are introduced by finite

aerial beam width and skip-distance effect. Multi-frequency

operation eliminates the latter defect, and also permits ionization to be measured. Results obtained during the I. G. Y.

with a single-frequency rotating-aerial sounder are presented,

showing the diurnal, seasonal and geographical characteristics

of Es occurrence. On particular occasions, movements have

been tracked and, under favorable conditions, the size and

ionization of the clouds determined. Earlier results obtained

with a fixed-direction aerial and multi-frequency technique

show similar diurnal and seasonal trends, and illustrate the

possibilities of the variable-frequency facility for simultaneous

measurement of cloud size and ionization. --Authors' abstract.

A-1124 Sheppard, P. A. (Imperial College, London), Dynamics of

the upper atmosphere . Journal of Geophysical Research, Wash.,

D. C, 64(12):2116-2121, Dec. 1959. 4 figs. , 8 refs. DLC.

A-1125 Shimazaki, Tatsuo, World-wide daily variations in the height

of the maximum electron density of the ionospheric F2 layer. Japan. Radio Research Laboratories, Tokyo, Journal, 2(7):

35-97, Jan. 1955. 7 figs. , 2 tables, 8 refs. , 14 eqs. DWB.

A-1125 Shimazaki, Tatsuo (Radio Research Lab. ), The characteristics of the F2 regions as deduced from the daily variations

in the ionospheric layer. Japan. Science Council. Ionosphere

Research Committee, Report of Ionosphere Research in Japan,

10(3): 124-142, 1956. 11 figs. , 14 refs. , 12 eqs. DWB--Summarized analytical results of the theoretical work involving

two models of the ionosphere are presented and discussed. A

general method for analysis of the ionospheric daily variations

is demonstrated and some of the salient deductions derived

are: 1. The F2 layer is produced at a level higher than that of

the maximum electron production as a result of height dependent coefficient. 2. A positive temperature (or scale height)
gradient is a very important existence in the F2 regions and

the thermal expansion during the daytime is larger in sunspot

maximum years than in minimum and in summer and/or lower

latitudes than in winter and/or higher latitudes. 3. The vertical drift velocity being non-uniform the increase or decrease

of amplitude and phase depend on altitude of formation of the

F2 regions. Seasonal and latitudinal variations do not depart

significantly, from daily variations except near the Equator.

--W.N.

A-1127 Shimazaki, Tatsuo, Structure of the F2 layer as deduced from

its daily variations. Japan. Radio Research Laboratories,

Journal, 3(ll):17-43, Jan. 1956. 15 figs. , 20 refs. , eqs.

DWB--The differential equations of motion and of continuity of

the ionospheric F2 regions are solved numerically on some probable assumptions of the upper atmosphere. If vertical tidal

drift is considered, the calculated daily variations have a strong resemblance to the observed ones in all latitudes ex- cept near the equator. The observed daily variations in the

maximum electron density in the F2 layer in various latitudes

and seasons may well be explained by changes in the height

of this critical level and in the phase of semi-diurnal vertical

tidal drift velocity. --From author's abstract.

A-1128 Shimazaki, Tatsuo (Radio Res. Labs. , Kokubunji, Tokyo),

Dynamical structure of the ionospheric F2 layer as deduced

from the world-wide daily variations. Journal of Atmospheric

and Terrestrial Physics, London, 15(1/2):108-115, Sept. 1959.

3 figs., table, 14 refs. DLC--Recourse was made to numerical calculations to find the effects of various nonuniform vertical motions due to diffusion, thermal and/or tidal variations

on daily variations in the F2 layer. A method was worked out

for detecting 24 hr periodicities in electron density distribution regardless of non-recurrent motions due to several causes.

The comparison of calculated and observed variations shows

that the Bradbury model is better than the Chapman model in

every respect. Special emphasis is placed upon the fact that

the effect of non-uniform semi-diurnal vertical drift velocities

with height gradient of both amplitude and phase is very important except near the equator. --Author's abstract.

A-1129 Shimazaki, Tatsuo (Radio Res. Labs. , Kokubunji, Japan),

Effect of the Sq current system on the ionospheric E- and Fl - layers. Journal of Atmospheric and Terrestrial Physics, London, 15(1/2): 77-82, Sept. 1959. 3 figs. , 4 refs. , 6 eqs.

DLC--The discrepancy between the observed foE or foFl and

those predicted by the Chapman theory is examined in detail.

The result shows that the Fl layer varies in a manner more re- gular than the E layer, and that the discrepancy in the E layer
334

may be attributed partly to the effect of scale height gradient,

but the principal cause certainly lies in the effect of Sq over- head current system. Discussion is made on the non-uniform

motion of vertical drift velocity produced by this effect, as

well as on the recombination coefficient and the scale height

gradient in these regions. --Author's abstract.

A-1130 Shimazaki, Tatsuo (Radio Research Lab. ), World-wide measurements of horizontal ionospheric drifts. Japan. Science

Council, Ionosphere Research Committee, Report of Ionosphere and Space Research in Japan, Vol. 13, No. 1:21-47,

1959. 8 figs. , 2 tables, 53 refs. DWB, DLC.

A-1131 Shirke, J. S. , Measurements of the ionospheric absorption on

2-5 Mc/s at Ahmedabad. (India). Institution of Telecommunication Engineers, Journal, 5(3):115-120, June 1S59. 3 figs. , 3 tables, 8 refs.

A-1132 Shmoys, J. , The reflection coefficient of the exponential

layer. Journal of Geophysical Research, 57(1):142-143,

March 1952. fig. , 8 eqs. MH-BH--Theoretical curves are shown for reflection coefficient as a function of frequency for

the absorption coefficients A - 10"20, 10"21 and 5 X 10"22

cm2 ( "X= 0°, <*> - 0), as calculated for the exponential layer,

and compared with MITRA's curves calculated by using the

parabolic approximation. The use of the exponential approximation makes variation of reflection coefficient more rapid. -- M.R.

A-1133 Shmoys, J. , Low frequency propagation in an exponential ion- ospheric layer. N. Y. Univ. Washington Square College of

Arts and Science. Mathematics Research Group, Contract AF

19(122) -42, Research Report, No. EM-51, April 1953. 16 p.

3 figs. , 6 refs. , 67 eqs. DWB-Recently, HEADING and WHIPPLE treated the problem of propagation of long radio waves in

an exponential ionospheric layer. They dealt with the case of

an obliquely incident plane wave, a vertical magnetic field,

and low collision frequency. The case treated here is that of

vertical incidence, oblique magnetic field, and both low and

high collision frequency. The results obtained do not agree

with experimental data. This is probably due to the fact that

coupling effects were neglected. An example is given in the

Appendix which shows that the omission of coupling terms,

however small their coefficients may be, is not always justified. --Author's abstract.

A-1134 Silberstein, Richard, High-frequency scatter sounding ex- periments at the National Bureau of Standards. Science, 118

(3078): 759- 763, Dec. 25, 1953. 4 figs. , 13 refs. DLC-The

four methods of studying backscatter echoes used at NBS

since 1946 are reviewed, their basic principles explained,

their merits and shortcomings discussed. Sample recordings

obtained with each of the methods are presented. The tech-
335

niques described are: 1) intensity vs range photography at

fixed frequency, 2) range-time recording at fixed frequency,

3) plan position indicator representation and 4) the sweep frequency technique. --G. T.

A-1135 Silberstein, R. , Sweep frequency backscatter: some observa - tions and deductions. Institute of Radio Engineers, New York,

Transactions, vol. AP-2(2): 56-63, April 1954. 12 figs. , table,

10 refs. DLC --Detailed analysis of records taken during two

periods in December 1952 and January 1953. "In one group of

observations over a 1150 km path on three undisturbed days,

the values of F2 layer maximum usable frequency scaled from

midpoint vertical-incidence ionospheric records and those determined by backscatter delay assuming ground scatter agree

almost within experimental error. In another three-day group

characterized by a low-latitude ionospheric disturbance with

low geomagnetic K indexes but considerable sporadic E activity, values of MUF determined from scatter were much too

high under the ground-scatter assumption, errors of about 30

percent being not uncommon. " The distant scatter in this

case appears to originate at the E layer. --Author's abstract.

A-1136 Silberstein, R. , The use of sweep-frequency backscatter data

for determining vertical and oblique-incidence ionosphere characteristics. IRE - URSI meeting, Washington, D. C. , May

1955. --It is possible to use sweep-frequency backscatter data

for obtaining monthly median values of x-kilometer maximum

usable frequencies at control points in a circle of radius one

half this distance. Diurnal graphs are shown for a 2370 km

path comparing the classical MUF as deduced from experimental backscatter data with the same MUF as deduced from midpoint vertical-incidence data and from actual oblique-incidence

characteristics. For the two cases shown, the median MUF

deduced from backscatter was about 2 percent higher than that

deduced from oblique -incidence records, while that deduced

from vertical incidence data was about 2 percent lower. Possible causes of anomalous echoes are discussed as are characteristics of some unusual records. A strong, sporadic morning-hour echo apparently associated with the E layer is described.

A-1137 Silberstein, Richard (Nat. Bur. of Stands. Boulder, Colo. ), A long-distance pulse-propagation experiment on 20. 1 megacycles. Journal of Geophysical Research, Wash. , D. C. , 63(3):445-466, Sept. 1958. 10 figs. , 3 tables, 15 refs. , 6

eqs. DLC--A pulse-propagation experiment was performed between Sterling, Virginia, and Maui, Territory of Hawaii, with

the object of studying the mechanism determining the classical

MUF at long distances, and also of obtaining a general idea of

the mode structure. Simultaneous oblique-incidence records of
336

the transmitter pulses were made at Boulder, Colorado, which

lies along the path. Some backscatter records were obtained

at the transmitter site; and vertical-incidence records were

made at the midpoint of the Sterling to Boulder portion of the

path. Results showed greatly differing mode structures between one day and the next, indicating that the long path is

very sensitive to ionospheric conditions, and also that M and

N reflection and layer tilts play an important part. Experimental evidence was strong that sporadic E ionization enables the

propagation of a wave over the path where F2 ionization at one

end of the path is not sufficient for reflection. --Author's abstract.

A-1138 Silberstein, R. (Nat. Bur. of Stands. , Boulder, Colo.), The

use of sweep frequency backscatter data for determining obli - que-incidence ionospheric characteristics, (dif. article).

Journal of Geophysical Research, Wash., D. C, 63(2):335-

351, June 1958. 12 figs. , table, 8 refs. DLC-The paper presents the results of comparisons of backscatter echoes, oblique-incidence pulse reception, and midpoint vertical-incidence echoes fro a 2370 km path, following an earlier study

for a 1150 km path. An attempt is made to find distinctive

characteristics of those backscatter records that afford accurate values of MUF for the 2370 km path. Some sporadic intermediate-distance echoes are discussed, and some difficult

night records are given. It is shown that present power and

antennas are inadequate for obtaining F2 propagated echoes

continuously, except on winter days. It is concluded that the

sweep-frequency backscatter technique is useful for obtaining

maximum-us able -frequency data for instantaneous or prediction

use over inaccessible areas, but that proper antennas and

skilled personnel are very important. --Author's abstract.

A-1139 Silberstein, R. (Nat. Bur. of Stands. , Boulder, Colo. ), The

origin of the current nonenclature for the ionospheric layers.

Journal of Atmospheric and Terrestrial Physics, London, 13

(3/4):382, Feb. 1959. DLC.

A-1140 Singer, Fred S. ; Maple, E. and Bowen, W. A , Jr. , Evidence

for ionosphere currents from rocket experiments near the geomagnetic equator. Journal of Geophysical Research, 56(2):

265-281, June 1951. 10 figs. , 4 refs. MH-BH--Results obtained from two aerobee rocket soundings made from a seaplane tender (Norton Sound) in March 1949, at 11°S and 89°W,

about 1000 miles west of Huancayo, Peru. Instrumentation described and shown diagramatically and in photograph. Calibration, flight history (to 345, 000 ft altitude) and method of analysis described. Magnetic field vs. time shown in graph for

both soundings, and compared with theoretical curve from in-
337

verse cube law. Departures from this law indicate existence

of a current layer in the atmosphere between 93 and 105 km.

Surface data from world-wide observatories indicate some disturbances on sun or earth, but no unusual disturbances. Authors claim results confirm dynamo theory of daily magnetic variation. --M. R.

A-1141 Singer, S. F. (Physics Dept. , Md. Univ. ), Rocket explora- tion of magnetic fields and electric currents in the upper atmos - phere. (In: Boyd, R. L. F. ; Seaton, M. J. and Massey, H. S.

W. (eds. ), Rocket exploration of the upper atmosphere. London, Pergamon, 1954. p. 256-260, figs. , 16 refs. ) DWB--

Tidal winds in the conducting layers of the earth's atmosphere

produce e. m. f. 's, and therefore a current system which is res- ponsible for many of the geomagnetic variations observed at

sea level. Rocket measurements at the magnetic equator have

now established the existence of this current in the lower £

layer of the ionosphere. (1) Because of the insufficient conductivity of even the whole atmosphere in the presence of a transverse magnetic field it has always been difficult to ac- count for the current on the basis of a theory which does not

require excessively high wind velocities. The experimental

results show that the current is distributed in only a very nar- row layer, extending from 93-105 km. (2) This finding forces

a reconsideration of the theory of ionospheric conductivity.

It leads to the suggestion that by means of Hall polarization,

which is set up perpendicular to the electric field and the

earth's magnetic field, the conductivity at the equator is re- stored to the original high value which would exist in the absence of the magnetic field. In this way it is now possible to

account for the ionospheric current system without invoking

the presence of extremely high winds, i. e. velocities much

greater than 100 km/hr. --Author's abstract.

A-1142 Singh, B. N. and Ram, R. L. , A peculiar type of periodic

fading. Journal of Atmospheric and Terrestrial Physics, 13

(1-2):190-191, Dec. 1958. 3 figs. , 2 refs.

A-1143 Singh, B. ft. and Ram, R. L. (both. Physics Lab. , Patna

Univ. , Patna), Rhythmic fading of short-wave radio signals.

Journal of Atmospheric and Terrestrial Physics, N. Y. , 16

(1/2): 145-155, Oct. 1959. 5 figs. , 9 refs. , 16 eqs. DWB,

DLC--The problem of periodic fading due to interference of a number of components of a sinusoidal radio signal has been

theoretically treated by considering it as equivalent to determining the resultant of a number of simple harmonic vibrations

of nearly equal frequencies. The practical bearing of the re- sults so obtained to fading curves of magneto-ionic origin particularly those caused by interference of three and four
338

components has been discussed. A number of typical fading

curves for short-wave radio signals transmitted from Delhi and

Calcutta have been described. Particular reference may be

made of curves which are very likely of magneto-ionic origin

and depict the complete sequence of events expected when

the value of the m. u. f. for the F2 layer passes across the

signal frequency due to the increase or decrease of the ionic

density of the layer. Fading curves which have been ascribed

to interference between waves singly and doubly reflected from

F2 layer and also those which are apparently caused by interference between waves simultaneously reflected from F2 and E

layers have also been described and their features discussed.

An example has also been given of such fading curves whose

origin appear to be obscure. --Authors' abstract.

A-1144 Singh, R. N. , Ionosphere and nature of fading patterns of re - ceived radio signals. Indian Journal of Physics, Calcutta,

28(3): 109-118, March 1954. 12 figs., 8 refs. DLC--Records

of reception of sw transmissions from Indian and other stations

are analyzed and compared with theoretical curves derived from

Rayleigh's probability formula. A study is made of (a) variations of the nature of fading with time of day for a given signal

frequency and transmitter distance, and (b) variation of the

nature of fading with transmission distance for a given frequency at different times of day. The results indicate that the

fading pattern is at least partially determined by the electron

density in the region of the ionosphere at which the received

waves are reflected. --Author's abstract.

A-1145 Singh, R. N. and Murty, Y. S. N. (both. Wireless Lab. , Dept. of Physics, Banaras, Hindu Univ. ), Limiting polarization curves for radio wave propagation in the ionosphere. Current Science, Bangalore, 27(5): 161-162, May 1958. 2 figs.,

6 refs. , 5 eqs. DWB, DLC--At Barnabas (dip angle: 36°26'N)

a study of the values for S and X, the multiples and submultiples of the gyromagnetic wave lengths A have been made.

The conformal method of representing the polarization of a radio wave propagated through the ionosphere in the presence

of earth's magnetic field by the above symbols is still retained.

A conclusion is reached that the limiting values of = 45

and X = only when the wavelength is less than 1/3 of the

gyromagnetic wavelength. The critical collision frequency was

calculated as 4. 49 Mc/s, the total magnetic intensity as

0. 446 Gans. -N. N.

A-1146 Singh, R. N. (Banaras Hindu Univ. , India) and Khastgir, S. R.

(Univ. College of Scien. , Calcutta, India), Study of "winds"

in the F region of the ionosphere during the unusual days in

the IGY calendar. Journal of Atmospheric and Terrestrial
339

Physics, N. Y. , 16(3/4): 376-383, Nov. 1959. 5 figs. , 4

refs. , 8 eqs. DWB, DLC--The three-spaced-receiver fading

records were taken at Banaras with vertical pulsed transmission at 3. 8-4. 2 Mc/s during the regular world days, world

meteorological intervals following the IGY calendar and also

during the SWI's. The records gave information about the

movements of the F region of the ionosphere during these un- usual days. The velocity and the direction of the "wind" were

obtained by the method of similar fades and the cross-correlation method. The experimental arrangements and the methods

of measurements have been described. Usually the velocity

of the F region "winds" was found to have high values during

the world meteorological intervals. The sudden reversal in

the direction of the F region "wind" round the midnight hour

was confirmed by the observations taken during the regular

world days. The sudden reversal in the direction of the

"wind" was found to be followed usually by extremely rapid

random fading, indicating turbulence in the ionosphere. The

fading records on the unusual days in the IGY calendar have

been classified and fully discussed with reference to the ran- dom and steady movements of the irregularities which exist

for a short time in the F region. --Authors' abstract.

A-1147 Singh, Tej Pratap, Fading of radio signal on medium wave

from oscillatory motion of lower ionosphere. Science and Culture, Calcutta, 17(ll):472-473, May 1952. 2 figs. , 15 refs.

MH-BH--Brief note on a fading phenomenon observed on 338. 6

m and 434. 8 m at Delhi. The theory of oscillatory motion of

the lower ionosphere is introduced to explain the phenomenon.

--W.N.

A-1148 Singleton, D. G. (Physics Dept. , Univ. of Queensland, Brisbane), A study of "spread F" ionospheric echoes at night at

Brisbane. Pt. 3, Freguency spreading. Australian journal of

Physics, Melbourne, 10(l):60-76, March 1957. 7 figs. , table,

21 refs., 9 eqs. DLC--The virtual range versus frequency

(P'f) records of the ionosphere made at Brisbane during 1952 and

1953 have been examined. The observations are interpreted in

terms of scattering from the clouds of enhanced ionization near

the F2 layer maximum which are believed to be responsible for

the scintillation of radio stars. It is suggested that there is a seasonal vertical movement of these clouds, the extent of

which increases with latitude. --From author's abstract.

A-1149 Sinno, Kenzi (Radio Res. Lab. , Tokyo), On the variation of

the F2 layer accompanying geomagnetic storms. Japan. Science

Council. Ionosphere Research Committee, Report of Ionosphere

Research in Japan, 7(1):7-14, 1953. 5 figs. , table, 5 refs. , 4

eqs. DWB--The separation of the variations in foF2 and h'F2
340

accompanying geomagnetic storms into two parts depending

on the universal and the local time, respectively, has been

attempted by the same method as the one employed in the case

of geomagnetic force components. The seasonal and latitudinal characteristics of the two parts and the developing process of the local-time part of the variations have been revealed. The deductions from the above are that the variation in

the local-time part is excited by the so-called "Sd current"

associated with the geomagnetic storm and that any trace of

moving disturbance from the auroral zone reported by some

workers is not clear enough to be found. --Author's abstract.

A-1150 Sinno, Kenzi (Hiraiso Radio Wave Observatory, Radio Research Laboratories), On radio propagation disturbances.

Japan. Science Council. Ionosphere Research Committee,

Report of Ionosphere Research in Japan, 10(3): 143-147, 1956.

5 figs. , 2 refs. DWB--Two types of geomagnetic storms are discussed in relation to forecasting of radio communication

conditions. The more severe effect on radio propagation is

found to arise from the 27-day recurrence storm period linked

to the M region and coinciding frequently with the passage of

the calm region of the solar surface of the sun's central meridian. The other nonrecurrent but effective storm type is re- lated to the active region of the sun. Accuracy of forecasting radio communication conditions is conversely proportional

to solar activity. --W. N.

A-1151 Skeib, Gunter, Die Peilung atmospharischer Storunqen durch

Synchronaufnahme von Richtunq und Wellenform. (Determination of atmospheric disturbances by synchronic recording of

direction and wave forms. ) Germany. Deutscher Wetterdienst,

Berichte, No. 4(22): 146-147, 1956. 9 refs. DWB, DLC-The

author discusses the detection of atmospheric disturbances by

means of the synchronous recording of direction and wave forms

with particular reference to the work of F. SCHINDELHAUER,

on the use of small sector sounding and cathode ray sounding,

the Potsdam synchronous recording apparatus, the automatic

atmospheric wave form recorder (ADCOCK and CLARKE), etc.

-I.L.D.

A-1152 Skeib, Gunter, Uber die Genauiqkeit der Bestimmunq von

Reflexionsh6hen und Entfernunqen atmospharischer Storunqen

aus ihrer Wellenform. (Precision of determination of reflection

heights and distances of atmospheric disturbances from their

waveform.) Zeitschrift Mr Meteorologie, Berlin, 11(5/6):129-

135, May/June 1957. 2 figs. , 8 tables, 2 refs. , 28 eqs. DWR

DLC-SCHONLAND's formula for determining the height of the

reflecting ionospheric layer (H) and the distance (D) of the

lightning discharge from the point of observation are subject
341

to errors which are the result of the fact that the precision of

the temporal fixation of the echo impulse in the wave form of

the disturbance has a finite limit owing to the resolving capacity of the instrumentation and irregularity in the reflection

process. Equations are developed for determining the mean

error of H and D when the values of p, q, r (impulses, f , and T+t (time differences between impulses) and D and H are taken from a wave record. Data on the mean error of D and II for different combinations of p, q and r for the specific wave

record are presented. Also equation for computing the mean

error of D and H from non-dimension values of p, q, r and -$l are derived and tables with data of N

IT

ctH ^ D kl J A. 2 j> a and values 2tL A+L

and £H for different combinations of p, qf r and for different

values of -77=- are presented. Also the errors arising as a re- sult of fast^determination of the order number in the wave form

are discussed. --I. L. D.

A-1153 Skinner, N. J. and Wright, R. W. , Equatorial ionospheric

absorption. Journal of Atmospheric and Terrestrial Physics,

9(2/3): 103-11 7, Aug. /Sept. 1956. 7 figs. , table, 18 refs. , 7 eqs. DWB--Measurements of ionospheric absorption were

made at Ibadan, Nigeria, mag. lat. 2 1/2 S by apparent re- flection coefficient at noon. Total absorption shows a linear

relation of -log e p /F with l/f2F instead of 1/f. Variation

with sun's zenith distance was proportional to (cos XT )0- * instead of (cos X )^' ^- These discrepancies with theory are

attributed to absorption in a Chapman-type D layer. Results

are compared with those from Singapore, Slough, Falkland

Islands and Prince Rupert. --C. E. P. B.

A-1154 Skinner, N. J. , Hope, J. et al. (both, Univ. College, Ibadan,

Nigeria), Horizontal drift measurements in the ionosphere near

the Equator. Nature, London, 182(4646): 1363-1365, Nov. 15,

1958. 2 figs. , (incl. photo), table, 6 refs. , eqs. DWB--

Horizontal drift in the ionospheric E and F layers have been

measured regularly at Ibadan, Nigeria (magnetic latitude 2^

S) ever since 1957. The method used for the measurements

and the results at Ibadan are compared with those at Singapore

and Waltair. Ibadan has larger drift velocity because of its

geographical position. --N. N.

A-1155 Slough, England. Radio Research Station, Electron density

and profiles in the ionosphere during the IGY (Official communi- cation from the DSIR Station). Journal of Atmospheric and Terrestrial Physics, 13(1/2): 195-197, Dec. 1953. 2 tables, 2 refs.
342

A-1156 Slusser, E. A. , Predicting performance of UHF and SHF

systems . Electronics, 24(6):116-121# June 1951. 14 figs.

,

2 tables, 18 eqs. DWB--Topographic and atmospheric conditions affecting propagation of ultra high frequency waves are discussed and illustrated. Curves illustrate effect of rain

and fog on SHF absorption. --M. R.

A-1157 Smith, Ernest Ketcham, Jr. , Worldwide occurrence of spora- dic E. U. S. National Bureau of Standards, Circular, No.

582, March 15, 1957. 278 p. numerous figs, and tables,

115 refs. DLC (QC 100. U555) -This monograph contains a thorough review of the literature and a discussion of the structure, energy sources, physical state and definition of Es; of

data obtained by vertical incidence (HF) and oblique incidence

(VHF) sounding. The limiting frequency is ( >) 5 mc. The

appearance of various types of Es (Huancayo, auroral, sequential, blanketing, stratified, transparent, etc.), the major

Es zones (equatorial, temperate, auroral), the geographical

variations, magnetic activity relations, reception at > 400

miles, field strength data, relation oi vertical to oblique incidence data and sources of energy for Es (solar corpuscles,

meteors, thunderstorms, winds and turbulence) are treated.

Meteors provide one, but not a major, source of Es. --M. R.

A-1158 Smith, E. K. and Knecht, R. W. (both, Nat. Bu. of Stands.,

Boulder, Colo. ), Some implications of slant-E. Journal of

Atmospheric and Terrestrial Physics, London, Special Supplement, 1957 (Proceedings of the Atmosphere Symposium, Oslo,

1956, Pt. 2), issued 1958? p. 195-204. 14 figs. , 12 refs.

,

4 eqs. DLC--Three examples of slant Es observed at College,

Alaska on Feb. 27, 1955, are shown in ionograms. Cases of

low latitude Es are also shown for the sake of comparison.

Ionograms of slant-Es, the linear representation of measured

and computed slant Es curves, the application of caustic focussing to slant Es through analogy to Dieminger's ground scatter

case, the possible modes of slant Es, the field strength at

frequencies near 2370 MUF, the isotropic case of scattered

power referred to backscatter, deviations/^ from specular conditions and some families of theoretical slant Es curves, are shown graphically. A feature of slant Es reported in a private

communication in 1951 is plotted on a linear instead of the

semi-logarithmic scale.

A-1159 Smith, Ernest K. , Jr. (NBS, Boulder, Colorado), Sporadic E

observed on VHF oblique-incidence circuits . AGARDograph,

Paris, No. 34:129-146, Sept. 1958. 11 figs., 8 refs. DWB

(529. 1323 N864a)--This paper is concerned with sporadic E as

observed on VHF circuits operated by the National Bureau of

Standards. The only circuit for which extensive analyses are
343

available is the initial ionospheric scatter circuit running

from Cedar Rapids, Iowa, to Sterling, Virginia, in the United

States, and operating at 27. 775 and 49. S Mc/s with high gain

rhombic antennas. During the last year, observations have

also been made over three frequency yagi to yagi circuits (30,

50, and 74 Mc/s) and four frequency rhombic circuits (30, 40,

50, 74), all circuits having their transmitters in Long Branch,

Illinois, and their receivers on Table Mesa, near Boulder,

Colorado. Another series of circuits operating on 50 Mc/s

extend from Guantanamo Bay, Cuba, down across the magnetic equator in South America. A companion circuit to this

later series runs from the northern part of Luzon in the Philippines to Okinawa in the Ryukyu Islands. Preliminary observations are presented for some of these circuits. A rather crude

but simple method is shown by which it is possible to predict

VHF field strength levels from vertical incidence data. Simultaneous fading rate measurements made on 30, 50 and 74 Mc/s

over the Long Branch to Boulder path indicate that fading during sporadic E normally has a period of a few seconds. However it is not uncommon for fading on 30 Mc/s to be more

rapid than on 50 Mc/s; 50 Mc/s to be more rapid than 74 Mc/s.

Results such as these seem to point towards a mechanism

where intense patches of ionization occur in the E region and

reflections take place when plasma densities pertinent to the

frequency and obliquity in question occur. When referred to

the inverse distance level, signal strengths during periods of

sporadic E propagation appear about 10 dB higher on 5 element

yagi antennas than on high gain rhombics. --Author's abstract.

A-1160 Smith, Ernest K. , Jr., Temporal and world-wide variations of

sporadic E. AGARDograph, Paris, No. 34:1-22, Sept. 1953.

15 figs. , 4 refs. DWB (629. 1323 U864a) --This paper attempts

to portray the gross geographical and time variations of sporadic E. As ionosonde data constitute the only reasonably uniform world wide source of information, the definition of sporadic E used here must be the same as that which has been es- tablished by international agreement for use in scaling vertical

incidence records. The majority of the data used in this analysis is for the period 1947-1954. Some preliminary analyses of

IGY ionosonde data, notably from the close-spaced equatorial

chain in South America are also included. It is left to other

papers in this meeting to distinguish between the different

types of Es. Further, an arbitrary choice is made to consider

only such cases of sporadic E for which the vertical incidence

critical frequency (fEs) is greater than 5 Mc/s. Temporal and

geographic variations are represented by contour maps for

which the contour parameter is the percentage of time for

which fEs exceeds 5Mc/s. Three sporadic E zones, equatorial,

temporal and auroral, are established on the basis of the diurnal
344

and seasonal variations of the gross sporadic E. The boundary between the auroral zone and the temperate zone is found

to occur near the 15% auroral isochasm. The equatorial zone

is taken to be a narrow ribbon centered on the magnetic equator and connected with the equatorial electrojet. The most

recent data available indicates that this ribbon is about four

hundred miles in width. —Author's abstract.

A-1161 Smith-Rose, R. L. and Barfield, R. H. , An investigation of

wireless waves arriving from the upper atmosphere. Royal

Society of London, Proceedings, Ser. A, 110:580-614, March

I, 1926. 10 figs. , 7 tables, 5 refs. , 15 eqs. DLC--Instrumentation, methods and experiments by which evidence for

the downcoming radio waves are obtained is discussed, including some conclusions and suggestions for future research.

»W. N.

A-1162 Smith-Rose, R. L. , International Scientific Radio Union:

meeting in Sydney. Nature, London, 171(4354): 628-631, April

II, 1953. DWB-Report of meeting Aug. 11-21, 1952. Subjects discussed included Measurements and Standards, Troposphere and wave propagation, Ionosphere and wave propagation. International Geophysical Year 1957-58, Terrestrial

atmospherics, and Radio-astronomy. --C. E. P. B.

A-1163 Smith-Rose, R. L. , Radio research station, Ditton Park,

Bucks . Nature, London, 175(4465): 921 -923, May 28, 1955.

2 figs. DWB--An account of the research program of the Station and its associated observatories (2 in British Isles, 5

overseas). This includes influence of meteorological conditions on transmission of very short waves, continuous study

of the ionosphere by vertical sounding, reflection and scattering, and noise background including sferics. The plan is

shown of a special building in course of erection to replace

temporary huts. --C. E. P. B.

A-1164 Smith-Rose, R. L. , The new Radio Research Station, Ditton

Park. Slough. Nature, London, 180(4578): 163-166, July 27,

1957. DWB--lSew permanent buildings of Radio Research Station were opened by SIR EDWARD APPLETON on June 20, 1957.

Radio research in the past 35 years summarized and present

program set out, especially in connection with IGY. --C. E. P. B.

A-1165 Sorensen, E. V. , Magneto-ionic Faraday rotation of the radio

signals on 40 Mc/s from Satellite 1957 (Sputnik I). (Abstract

of article issued by Danish Academy of Technical Sciences,

Microwave Laboratory, Copenhagen, as its Report P 1765,

June 24, 1959). --
345

Some of the fadings of the 40 Mc/s signals from Sputnik I during morning transits are assumed to originate in Faraday

rotation in the ionosphere. This has been investigated for

the transit of Oct. 12, 1957, 5. 30 GMT, for which the orbit

was known with reasonable accuracy. The fading records show

an increasing fading rate during the last part of the transit.

This is contrary to the simple theory based on the assumptions

of a flat earth and a homogeneous ionosphere, from which a constant fading rate should be expected. The main reason why

simple theory did not apply in this case, is that the satellite

travels through the twilight zone from night towards day, i. e. from low to high ionization. The Faraday rotation is calculated by means of data for the orbit, magnetic field maps and

predictions of the ionosphere conditions. The result is in

good agreement with the observation when a high ionization between the altitude of maximum ionization and the satellite is

assumed. The effect of refraction is estimated by means of

the perturbation theory. It increases the Faraday rotation from

to 19 percent during the transit. It is concluded that it is

difficult to obtain detailed information on the state of the ionosphere by means of such fading records, especially when

the frequency is so low that the refraction becomes significant. --Author's summary.

A-1166 Somayajulu, Y. V. (Wireless Res. Lab., Andhra Univ. ),

Oblique incidence pulse observation of the ionosphere near the

maximum usable frequency. Current Science, 21(6): 155-156,

June 1952. fig. , ref. DWB--Pulse transmission experiments

at frequency 21. 7 Mc/s over a distance of about 1500 km at

Delhi indicate that APPLETON's and BEYNAN's explanation of a parabolic region of the reflecting layer (F2) is correct since

the sequence of observation was similar and particularly because a sudden increase in the signal intensity was clearly

observed. Detailed account to be published. --W. JN. A-1167 Somayajulu, Y. V. ; Rao, B. Ramachandra and Bhagiratha

Rao, E. , Investigation of travelling disturbances in the ionosphere by continuous -wave radio. Nature, London, 172(4383):

818-820, Oct. 31, 1953. 3 figs. , 9 refs. DWB-The first letter describes a simple method using continuous short-wave

signals and oblique-incidence pulses from Madras recorded

at Waltair, 640 km distant. A typical record indicates velocities of 200-400 m/s, larger and less uniform by day than by

night. The second letter describes a similar method using two

short-wave transmissions on close wave lengths. --C.E. P. B.
346

A-1168 Southworth, Mason P. (ARRL-IGY Project Supervisor), The

ARRL-IGY propagation research project. American Geophysical Union, Transactions, 39(5): 995-997, Oct. 1958. DWB,

DLC --Outline of program, the reporting and recording of data,

the circulation of PRP news among the observers and the further uses of the propagation research data during the IGY are discussed. --N. N.

A-1169

A-1170

Southworth, M. P. (Radio Propagation Lab. , Stanford Univ. , Calif. ), Night-time equatorial propagation at 50 Mc/s: first

results from an IGY amateur observing program. Journal of

Geophysical Research, Wash., D. C. , 65(2): 601 -607, Feb.

1960. 9 figs. . 10 refs. DLC.

Srivastava, C. M. , The propagation of a radio atmospheric.

Institution of Electrical Engineers, London, Proceedings, Pt.

B, 103(10): 542-546, July 1956. 4 figs. , 2 tables, 9 refs.

,

12 eqs. DLC --The smooth oscillatory type of atmospheric is

interpreted on the basis of optical properties of wave guides.

The pulse is considered to originate from a pilot streamer and

to be rectangular with a duration of 100 microsec. The propagation path is the space between the earth and ionosphere,

taken as parallel planes. The wave form characteristics are calculated and agree with observation. --C. E. P. B.

A-1171 Srivastava, J. P. and Rajan, V. D. , Anomalous variations

in the angle of downcoming radio waves and their bearing on

the fading of short wave signals . Indian Journal of Physics,

25(6):287-297, June 1951. 9 figs. , table, 5 refs. , 8 eqs.

DLC--A detailed study of the problems of angle of arrivals

and intensity variations of short-waves between the 16 and

41 m band. Cause and effect of circumstances resulting in

abnormal values are discussed. Single and double reflected

waves give normal values of angles whereas rays arising

from magnetoionic splitting give anomalous variation and

values of angle. Observational examples are presented. -- W. N.

A-1172 Staley, Raymond C. , Some problems in modelling water waves

for the study of back-scattering of microwave radio energy.

Deutsche Hydrographische Zeitschrift, Hamburg, 11(6) :255-

258, 1958. 12 refs. , 11 eqs. English, German and French

summaries p. 255. DWB.

A-1173 Staley, R. C. , High altitude observation techniques.

130(3386): 1435, Nov. 20, 1959.

Science,
347

A-1174 Stanley, J. P. , The absorption of long and very-long waves

in the ionosphere. Journal of Atmospheric and Terrestrial Physics, l(2):65-72/ 1950. 4 figs. , 9 refs. MH-BH--The Radio

Research Group at Cavendish Laboratory made a detailed study

of the variations in reflection of long and very long waves from

the ionosphere during the daytime and at night. The experimental curves are presented and an attempt made to explain

theoretically the variation from summer to winter and noon to

night. Older linear or parabolic models of ionization density

are abandoned in favor of one in which an absorbing layer of

low ion density (D region) and of great thickness underlies

the main reflecting region. The exponential model is developed in detail and the sunset effect explained qualitatively. -- M.R.

A-1175 Stanley, J. P. , Ionospheric reflection of very long radio

waves . Canadian Journal of Research, Section A, Physical

Sciences, 28(6): 550-557, Nov. 1950. 3 figs. , 6 refs. , eqs.

DGS--The "tarnished mirror" model of the long wave reflecting

region of the ionosphere is used to calculate the variation of

reflection and conversion coefficients with angle of incidence,

assuming the earth's magnetic field to be vertical and the re- flection and conversion coefficients at vertical incidence in

an oblique magnetic field inclined 23 to the vertical. The

solution of the equations of propagation under both conditions

is presented. It was found that the assumption of a vertical

magnetic field theory did not lead to errors in the calculated

sky wave reflection and conversion coefficient that were greater than about 10 percent although the field was inclined as much as 23 to the vertical. --I. L. D.

A-1176 Stanford Univ. Radio Propagation Laboratory, Study of sporadic ionization of the upper atmosphere by means of backscattered radio signals . Contract DA-04-200-ORD-181, Status

Report, No. 1, July 1-Oct. 1, 1952. 7 p. Photostat of typescript. DWB--Report on the initial phase of a project aimed

at the collection of data on the nature and characteristics of

"clouds or patches of ionization" appearing sporadically in

the E layer, and on concurrent weather phenomena. A con- tinuously operating scatter-sounding apparatus (completed and

installed as the first task undertaken toward the project) is

described and its operation explained. --G. T.

A-1177 Staras, H. , Scattering of electromagnetic energy in a rand- omly inhomogenous atmosphere . Journal of Applied Physics,

23t|0):1152- , 1952. --First-order perturbation theory is used

to derive an integral representing the scattered power at a re- ceiver resulting from random inhomogeneities in the propagating medium. The expression obtained corresponds with that
348

used by Booker and Gordon, but instead of the space-correlation function of refractive index used by them a time-correlation function is introduced which permits evaluation of the

time average of the scattered power; this time-correlation

function is directly measurable. For small-scale turbulence

the average scattered power is not affected by the particular

model of atmospheric turbulence chosen for large-scale turbulence the results depend on the particular time-correlation

function chosen and on particular assumptions regarding the

scattering bodies.

A-1178 Steiger, W. R. (Univ. Hawaii) and Matsushita, S. (High

Alt. Obs. , Univ. Colorado), Photographs of the high-altitude

nuclear explosion 'Teak". Journal of Geophysical Research,

Wash., D. C, 65(2): 545-550, Feb. 1960. 7 figs. , 4 refs.

DLC.

A-1179 Stein, Sidney (Ionosphere Research Lab. , Penn. State Univ. ), The role of ionospheric -layer tilts in long-range high-freguency

radio propagation. Journal of Geophysical Research, Wash.

,

D. C. , 63(1):217-241, March 1958. 11 figs. , 16 refs. , 2+

eqs. DLC--The role of ionospheric -layer tilts in long-range

HF and VHF radio propagation is discussed. A derivation of

the ray trajectories for a simple ionospheric model is given.

The characteristic ranges on the radio frequencies observed

between 12 Mc and 30 Mc are the same; but sometimes there

is a complete absence of intervening ground backscatter. The

back scatter from the distant E region and the reflection from

the upper side of the E layer are very noticeably associated

with F-layer tilts. --N. N.

A-1180 Stoffregen, W. , Ionospheric measurements in connection with

thunderstorm research. Arkiv for Matematik, Astronomi och

Fysik, Stockholm, 39(4), No. 19, 1944. 10 p. 13 figs. , 6

refs. , eqs. DLC—At the Institute of High Tension Research,

Upsala, complete equipment for ionospheric research has been

constructed and operated to study the relation between thunderstorms and conditions in the ionosphere. The ionization in E

and F layers has been measured continuously and the abnormal

increase in E region ionization often observed during the

summer is found to be caused by thunderstorms. During strong

earth magnetic activity the effect of thunderstorms on the ionosphere is found to be much lower. These investigations are

to continue over several thunderstorm periods. --Author's abstract.

A-1181 Stoffregen, W. , A panoramic ionospheric echo recorder. Terrestrial Magnetism and Atmospheric Electricity, 53(3) :269-

271, Sept. 1948. 3 figs. DLC-
349

Oscillograph arrangements connected to the receiver yield a 18 x 9 cm standing picture of the ionospheric layer on a 9 in.

cathode-ray tube screen with 10 sec afterglow. --W. N.

A-1182 Storey, L. R. O. , Whistlers. Scientific American, N. Y. , 194(1) :34-37, Jan. 1956. figs. DWB, DLC -Whistlers differ

from radio atmospherics in that they occur at long wave lengths, are drawn out rather than abrupt (as are clicks) and occur

repeatedly at fixed intervals (as echoes do) when they are re- flected back from the opposite hemisphere via the ionosphere.

If they originate in opposite hemispheres, no click precedes

whistlers. The theory is explained and illustrated and recorders (sound spectrograph) and records described and illustrated.

The timing of the whistlers and (their length) after the lightning click gives a clue to the distance travelled, if frequency

is taken into account. Results indicate that atmosphere (400

electrons/cc) extends up to 7, 000 miles instead of 1500 miles

and consists of ionized hydrogen, perhaps picked up by geomagnetic field as earth passes through space. --M. R.

A-1183 Storey, L. R. O. (Nat. Center of Scien. Res. , Paris), The

joint use of the ordinary and extraordinary virtual height curves

in determining ionospheric layer profiles. U. S. National

Bureau of Standards, Journal of Research, Sec. D, 64(2):111-

124, March/April 1960. 5 figs. , table, 12 refs. , 74 eqs.

DWB, DLC.

A-1184 Straker, T. W. , The ionospheric propagation of radio waves

of freguency 16 kc/s over short distances. Institution of

Electrical Engineers, London, Proceedings, Part C, 102(1):

122-133, March 1955. 18 figs. , 18 refs. DLC -Investigations carried out between March 1948 and Oct. 1949 over a 90 km path from Rugby to Cambridge at 17 kc/s. The abnormal

component of downcoming wave was isolated and measured

separately. Results show reflection occurred from height of

72 km in daytime and 87 km at night, with apparent height of

reflection varying with zenith angle of sun (16. 8 km in summer and 13. 5 km in winter). Diurnal cycles of amplitude

change and phase change occurred independently. Sunrise

effect on amplitude occurs 1 hour before effect on phase. No

evidence was found of waves reflected twice from ionosphere.

During and after magnetic storms diurnal variations were abnormal (for as long as 10 days). --M. R.

A-1185 Stranz, Dietrich, A study of impressive wave formation in

the atmosphere . Chalmers Univ. of Technology, no. 71, 1948.

GiSteborg, Sweden.
350

A-1186 Stranz, Dietrich, Eng beqrenzte Ionisationswolken in 125 km

H6he wahrend einer Nordlichtst6rung. (Isolated ionization

clouds at height of 125 km during an auroral disturbance.

)

Archiv der elektrischen tfbertragung, 4:213-216, (1950). 3

figs. , table. Reprint available. MH-BH—From 22 h on Sept.

15, 1948 to 1 h on 16th at Goteborg 3 MHz waves showed isolated ionization clouds beginning at 200 km and descending

to 125 km. Attributed to a bundle of deflected corpuscular

rays. There were pulsations of 3-5 sec in intensity of echo.

This observation raises a number of problems. The magnetic

disturbance vector is analyzed. --C. E. P. 5.

A-1187 Stranz, Dietrich, Erqebnis einer Fade-out-Statistik. (Results of fade out statistics. ) Archiv der elektrischen Ubertragung, 4:217-218, (1950). 7 refs. Reprint available. MHBH--Distribution of spots about central meridian of sun on

days with total fading and without fading at Goteborg compared for Aug. -Dec. 1948. This showed a significant rarity

of spots near central meridian on days without fading. -- C.E.P.B.

A-1188 Stranz, Dietrich, The lowest of the ionized layers of the

upper atmosphere . Tellus, 2(3): 150-157, Aug. 1950. 4

tables, 25 refs. DWB—The effects of ionization on chemical

composition of the layer from 75 to 100 km height (D layer)

and on electron density, absorption, radio propagation, etc. are treated. Various theories of the formation of the D layer

are discussed. --M. R.

A-1189 Strohfeldt, M. ; McNicol, R. W. E. and Gipps, G. de V. , Ionospheric measurements, at oblique incidence over eastern

Australia. Australian Journal of Scientific Research, Physical

Sciences, Ser. A, 5(3):464-472, Sept. 1952. 3 figs. , 3 plates,

10 refs. DWB--An account is given of night observations of

oblique incidence pulse transmissions on 5. 8 Mc/s over a baseline of 763 km, using a responder technique. The experiments aimed at measuring apparent path lengths as a guide to

the identification of the reflection to the echo system received

after ionospheric reflection. A correlation of Es occurrences

as observed at oblique incidence and vertical incidence near

the midpoint of the trajectory was effected, and certain characteristics of the Es layer are presented. Unusual records of

Pedersen rays are reproduced and sudden height increases and

diffuseness of F2 echoes are discussed. A check on the oblique incidence theory using a Millington transmission curve

on vertical incidence hf records yielded reasonable agreement

between measured and deduced reflection heights, although

there is evidence of a tendency for the predicted obliquity

factor to be too low. A rough analysis of oblique incidence
351

penetrations yielded an average value for the frequency separation of the magnetoionic M. U. F. 's close to half the gyromagnetic frequency. --Authors' abstract.

A-1190 Sugar, G. R. (Nat 'I. Bureau of Standards, Wash., D. C. ), Some fading; characteristics of regular VHF ionospheric propagation. Institute of Radio Engineers, N. Y. , Proceedings,

43(10): 1432-1436, Oct. 1955. 11 figs., 3 refs. , eqs. DLC--

Some short-term fading characteristics of a type of ionospheric

propagation first described by BAILEY et al (See item No.

A-94) are presented and discussed. Continuous wave

transmissions from Cedar Rapids, Iowa, on 49. 8 mc were re- ceived at Sterling, Va. , on either rhombic or Yagi antennas

directed toward the transmitter. The second detector output

of a linear receiver was used to provide a voltage proportional

to the envelope of the received signal. This fluctuating voltage was recorded, edited, and then analyzed to determine

the probability distribution and autocorrelation function of the

signal envelope. The correlation of the envelopes of signals

received on spaced antennas was similarly determined for an- tennas spaced both normal and parallel to the transmission

path. --Author's abstract.

A-1191 Sullivan, A. W. , Van Valkenburg, H. M. and Barney, J. M. , Low-freguency atmospheric radio noise in Florida. American

Geophysical Union, Transactions, Pt. 1, 33(5):650-656, Oct.

1952. 11 figs. MH-BH--This study of diurnal and seasonal

variations in average noise level and frequency spectra is

based on the data of 15, 52, 189 and 530 Kc frequencies obtained since 1947, eight miles from Gainesville, Florida,

where man-made noise is at a minimum and the noise levels

are quite high from March to Sept. The use of 23 m high an- tennas enables reception of noise from any azimuth on the

Signal Corps BC969 and the BC779 receivers used. The re- sults show: 1) that noise levels are almost inversely proportional to frequency in the 10-500 Kc range; 2) the possibility

that the average noise spectrum is constant at the source of

the noise, hence, if this is true, atmospheric noise will prove

valuable as a tool in studies of propagation; 3) diurnal and

seasonal variation in noise intensity depends on frequency

and propagation conditions; 4) SID generally tend to cause

an increase of noise. --W. N.

A-1192 Sullivan, A. W. ; Hersperger, S. P. and Brown, R. F. , Investigation of atmospheric radio noise. Florida. Univ. at

Gainesville, Engineering and Industrial Experiment Station,

Contract AF 19(604) -876, Scientific Report, No. 10, Jan. 20,

1956. 95 p. 14 figs. , 6 refs. , 31 eqs. 52 abstracts. Atmospheric waveforms bibliog. p. 45-57 (151 refs. ).
352

Also: Sullivan, A. W. ; Brown, R. F. and Nawricki, P. J. , Scientific Report, No. 11, April 15, 1956. 79 p. 22 figs. , 3 tables, 25 refs. , 26 eqs. DWB--In Report No. 10 the effect

of atmospheric noise on a radioteletype system is discussed

and a statistical model presented. Waveforms received from

380 mi are analyzed at source and at the receiver and the

noise peaks found to be distributed according to a log-normal

distribution law at the receiver but not at source. A bibliography on p. 45-57 lists 151 references of which 52 are abstracted or summarized (at some length) on p. 58-92, and an

author index appended. The items are classified according

to: (1) lightning discharge mechanisms, (2) electromagnetic

radiations from lightning and (3) ionosphere and propagation

of sferics. In the second report the correlations between the

performance of the teletype and the noise distribution functions are examined and studies of VLF ground-wave polarization begun. --M. R.

A-1193 Sulzer, Peter G. and Underhill, B. B. (Pa. St. Coll. Radio

Propag. Lab. ), Preliminary vertical incidence equivalent

height versus time recordings on 150 Kc/s . Pennsylvania.

State College. Radio Propagation Laboratory, Contract AF

19(122)-144, Basic Ionospheric Research, Technical Report,

No. 8, Dec. 15, 1949. 13 p. 34 figs. , 3 tables, 6 refs.

DWB--Vertical incidence equivalent height versus time measurements at 150 Kc/s are described in this report. The preliminary measurements reported were obtained during the interval March 4 to June 21, 1949. The transmitting and receiving equipment utilized for the measurements is described in

some detail. Reproductions of the photographic records procured during the above interval are included for each day on

which satisfactory records were obtained. Some initial cor- relations and interpretation of the data are attempted. --Authors' abstract.

A-1194 Swenson, George W. , Jr. , VHF diffraction by mountains of

the Alaska range. Univ. of Alaska, Contributions of the Geophysical Institute, Series B, No. 14, 1956. Reprinted from:

Institute of Radio Engineers, Proceedings, 44(8): 1049-1050,

Aug. 1956. -Usable TV signals at 57 and 200 Mc/s were re- ceived during the winter 1953-54 at Lake Minchumina (across

the mountain ridge including the Mt. McKinley 20, 300 ft and

the Mt. Foraker 17, 395 ft) from two transmitting stations 200

mi away at Anchorage, Alaska. The subsequent series of

experiments conducted, and discussed here, substantially

support the validity of the knife-edge approximation. --W. N.
353

A-1195 Symposium on ionospheric drifts. Journal of Scientific and

Industrial Research, Sec. A, New Delhi, 14(10):482-485,

Oct. 1955. 2 refs. DWB, DLC -Report of symposium held at

the National Physical Laboratory of India at New Delhi on

July 30, 1955, in which ionospheric drifts and their measurements were discussed by Dr. K. S. Krishnan; S. N. Mitra,

K. R. Ramanathan; Nanda Bhargava and others. Fading drifts

in ionospheric records, the 150 km echo at nighttime, vertical

ion transport and other aspects of this special problem were

considered. --M. R.

A-1196 Tantry, B. A. P. and Khastgir, S. R. , Studies in fading of

medium wave radio signals. Indian Journal of Physics, 25

(5):217-232, May 1951. 12 figs. , 4 tables, 13 refs. , eqs.

DLC--Evening and early night hour data are presented in

curves and tables. Two types of fading pattern were observed:

(1) Periodic or quasi-periodic with distinct slow and quick periods, of which the slow one is attributed to ionospheric interference described by APPLETON and BEYNON (1947) whereas

the quick one is considered due to the vertical movement of

the ionospheric layer that usually occurs at night. The Doppler-beat interpretation (order 3, 5 m/sec) and expression for

the periodicity are given. (2) Random fading. The analysis

disagrees with RAYLEIGH's formulas, possibly explainable

by the existence of rays following slightly different paths.

Observations of more than one peak (for distant stations) in

the distribution curve must be due to single and double E layer reflections. --W. N.

A-1197 Tantry, B. A. P. and Srivastava, R. S. (both, Banaras Hindu

Univ. ), Preliminary studies of the energy spectrum of near

atmospherics over the freguency range 3-15 kc/s. Journal of

Scientific and Industrial Research, Sees. B and C, New Delhi,

17(2):47-51, Feb. 1958. 4 figs. (incl. photo), table, 4 refs.

DLC--The energy spectrum of near atmospheric pulses has been

investigated by the tuned amplifier method. Narrow band amplifiers, tuned to different sets of frequencies within the range

3 to 15 kc/s were employed to obtain simultaneous responses

of the individual atmospheric pulses. The sinous wave patterns delineated on the oscillograph screens were focussed by

suitable lenses on a photographic film. The wave form pattern

of the same atmospheric pulse was also recorded simultaneously employing an automatic atmospherics recorder. The distances of the sources of atmospherics were obtained from the

time intervals between the successive pulses reflected from

the ionosphere. The study of the relative amplitudes of the

wave patterns shows that, for most of the atmospherics re- corded near the source, the amplitude distribution has a maximum between 8 and 10 kc/s. The low frequency tuned amplifiers and the automatic atmospherics recorder are briefly des

cribed. --Authors' abstract.
354

A-1198 Tantry, B. A. P. and Srivastava, R. S. (both, Banaras Hindu

Univ. , India), Polarization of atmospheric pulses due to successive reflections from the ionosphere. Journal of Geophysical Research, Wash. , D. C. , 63(3): 527-538, Sept. 1958.

6 figs. , 3 tables, 9 refs. , 16 eqs. DLC--In determining the

direction of arrival of atmospherics by using a "cross ed"-loop

cathode-ray tube direction-finder, it was found that, on occasions, in addition to the usual straight-line responses on the

oscillographic screen, there were elliptic patterns of gradually decreasing eccentricity, size, and tilt-angle. The observed elliptic patterns are considered as due to the abnormal

polarization of the atmospheric pulses reflected successively

from the ionosphere, while the linear responses are due to the

direct atmospheric pulses. It has been shown in the paper

how from the observed polarization ellipses and the orientation of the linear response, the polarization characteristics

of the atmospheric pulses reflected successively from the

ionosphere can be determined. On analyzing the observed

patterns, it is found that, in general, the phase-difference

between the normal and abnormal components increases gradually with the increasing order of reflection. It is suggested

that the observed straight lines in the D/F pattern, bunched

within a small angle, are due to the radiation pulses originating at the branching points of a long horizontal or slightly inclined lightning channel from one cloud to another. The approximate calculation from the observed angular width of the

bunch of straight lines has shown that the horizontal length

of the channel is consistent with SHIPLEY's observations of

horizontal lightning channels along the lower edge of a cloud.

--Authors' abstract.

A-1199 Tanzman, H. D. ; MacLeod, G. A. and Scott, W. T. , Doppler

satellite measurements . Institute of Radio Engineers, Proceedings, 47(l):75-76, Jan. 1959. 5 figs. , ref.

A-1200 Taubenheim, Jens (Berlin-Adlershof), Messunqen der Absorption von Kurzwellen in der Ionosphate . (Measurement of the

absorption of short waves in the ionosphere. ) Freiberger

Forschungshefte, Ser. C, Geophysik, No. 29:1-18, Oct. 1956

(issued Berlin, Akademie Verlag). 8 figs. , 22 refs. , 10 eqs.

DWB—A review of recent knowledge concerning absorption of

short radio waves in the various ionospheric layers, methods

of measurement, the relation to propagation and the relation

of propagation to knowledge of the electrical properties of

these layers of the upper atmosphere. Diurnal, seasonal, sunspot cycles and eclipse effects or variations are discussed

and illustrated. Focussing and de-focussing are illustrated

schematically. --M. R.
355

A-1201 Taylor, William L., Description of recording equipment to be

used in the study of whistling atmospherics . U. S. National

Bureau of Standards, MBS Report, No. 3559, Nov. 30, 1955.

25 p. 9 figs. DWB--The discovery, nature and cause of

whistlers (atmospherics that bounce back and forth from opposite hemispheres along magnetic lines of force via the ionosphere) are reviewed and equipment designed by the National

Bureau of Standards for use in a project which they are setting

up to verify Storey's theory (by installations in Bermuda and

the Falkland Islands), described and illustrated. Simultaneous

recordings will be made for a 3-5 min period every 30 min for

12-24 hrs, two or three times a week. Magnetic tapes will be

analyzed at Stanford University. --M. R.

A-1202 Taylor, William L. and Lange, L. Jerome (both, Nat'l. Bureau

of Standards, Boulder, Colorado), Some characteristics of

VLF propagation using atmospheric waveforms . Conference

on Atmospheric Electricity, 2nd, Portsmouth, N. H. , May

1958, Proceedings, issued 1958. p. 609-617. 6 figs. , 6

refs. , 3 eqs. DWB (M(055) C748pr) -Simultaneous observations have been made of the waveforms of atmospherics

("sferics") at four widely separated stations. VLF attenuation characteristics have been computed by comparing the

spectra of the waveforms recorded at the four locations for

each discharge. The results of some preliminary measurements

of VLF attenuation are presented for the band of frequencies

from 4 kc to 30 kc at distances of 1200 km to 6500 km. -Author's abstract.

A-1203 Theissen, Emil, Quelgues resultats relatifs a la freguence

critigue et au facteur de transmission de la couche ionospherigue Fl. (A few results concerning critical frequency and

propagation factor of the ionospheric Fl region. ) Acad£mie

des Sciences, Paris, Comptes Rendus, 237(18): 1104-1106,

Nov. 2, 1953. 3 refs. , 5 eqs. DWB-Assuming z for zenithal

angle of the sun and K for critical frequency at z = 0, the

author proposes two formulas representing (1) critical frequencies: foFl = K cos nz ; and (2) propagation factor: (M3000)Fi

= M cos mz . From measurements made at Freiburg, values

of n and m are given as 0. 22 and 0. 08 (+ 0. 02) respectively.

Data available for Freiburg and for Washington are discussed.

A relation between ionospheric propagation and solar activity

is indicated. --G. T.

A-1204 Thomas, J. A. and McNicol, R. W. E. , Automatic recording

of the direction of arrival of radio waves reflected from the

ionosphere. Institution of Electrical Engineers, London, Proceedings, Pt. B, 102(6): 793-799, Nov. 1955. 11 figs. , table,

10 refs. DLC-
356

A-1205

Equipment is described which, for a fixed frequency, simultaneously determines the direction of arrival of all resolved

pulses reflected from the ionosphere by measuring the phase

differences for two pairs of fixed orthogonal spaced-loop serials. The vector sum and difference of the signals for each

pair of loops in turn are formed in a special unit. These are amplified in normal receivers and the rectified video outputs

applied to the Y and X plates respectively of a cathode-ray

tube. The orientations of the resulting lines are thus governed

by the phase differences between the signals at the pairs of

loops. Pulse resolution is achieved by the simultaneous application of a time-base in the X direction. Phase balanced

receivers are not required; since the phase sensitive portion

of the equipment is confined to the loops, pre-amplifiers and

the sum-and-difference unit, the system is stable enough to

run without attention for up to one week. --Authors' abstract.

Thomas, J. A. (Univ. of Queensland, Brisbane), Sporadic E

at Brisbane. Australian Journal of Physics, Melbourne, 9(2):

228-246, June 1956. 19 figs. (incl. photos), table, 28 refs.

DLC —Further data are presented in support of MC NICOL and

GIPP's classification of two types of sporadic E at Brisbane

(lat 27. 5 S), namely, sequential type (Ess) and constant

height type (Esc). Information is given on the occurrence,

critical and blanketing frequencies, reflection coefficients,

range spreading, vertical movements, and lateral extent of

Es patches. No correlation is found with sunspot cycle,

meteor occurrence, or thunderstorm activity. Scattering from

a turbulent medium is not responsible for Esc at Brisbane.

Tidal movement is regarded as most likely cause of both types

of Es. --Author's abstract.

A-1206 Thomas, J. A. (Physics Dept. , Univ. of Queensland, Brisbane), Double layer phenomena in the E region. Australian

Journal of Physics, Melbourne, 9(4): 575-577, Dec. 1956. 8

figs. , 4 refs. DLC--Six ionospheric P'f and P't (2. 28 Mc) re- cords are presented for Brisbane, and models sketched to show

how a multiple-layer effect could be produced by a sloping Es

layer. It is presumed that the moving Es layer could be made

up to an aggregate of disk-like clouds with sloping regions of

the order of those postulated. Large sloping regions necessary to produce high multiple Es echoes similar to F layer

echoes are rare (over a two year period) and even doubtful

existence. --M. R.

A-1207 Thomas, J. A. ; Svenson, A. C. and Brown, H. E. (Univ. of

Queensland, Brisbane), Ionospheric recorders and sporadic E. Australian Journal of Physics, Melbourne, 9(1):159-161, March

1956. 2 figs. , plate, 4 refs. DLC--
357

Repetitive sequences of records of Es frequency were made

with different receiver gains (every 2 minutes) showing that

fEs and fbEs values are reliable for stations in mid-latitudes.

Marked variations in Es between stations may then be due to

varying nature of the Es itself, and not as suggested by

RAWER (1949), BOOKER (1950) and MC NICOL and GIPPS

(1951), due to variations in the sensitivity of the recording

equipment. Graphs and recorder records show no dependence

of fEs on receiver sensitivity up to at least 6dB above normal

recording sensitivity. --M. R.

A-1208 Thomas, J. A. (U. Queensland, Australia), Classification

of sporadic E. AGARDograph, Paris, No. 34:33-36, Sept.

1958. fig., ref. DWB (629. 1323 N864a) -The various approaches to the problem of classification are discussed, and

the inevitable defects of various local classifications when

the problem is one of determining the world-wide behavior of

sporadic E are pointed out. The present IGY Classification

is given, and a few comments are made on the analysis of the

data so obtained. --Author's abstract.

A-1209 Thomas, J. A. (U. Queensland, Australia), Outline of suggested theories of sporadic E. AGARDograph, Paris, No. 34:

23-30, Sept. 1958. 40 refs. DWB (629. 1323 N864a) -The

various theories are briefly examined in the light of present

day knowledge of sporadic E obtained by variety of techniques. The proposals for reflection mechanisms are outlined

and these are followed by a short analysis of the suggested

energy sources. Some comment is made on the general applicability of the various theories and the frequent lack of the

vital connecting link between a proposed energy source and

the reflection mechanism. --Author's abstract.

A-1210 Thomas, J. A. , Satellite Doppler measurements and the ionosphere. Journal of Atmospheric and Terrestrial Physics, 13

(3/4): 376-379, Feb. 1959. fig. , 2 refs.

A-1211 Thomas, J. A. (Dept. of Phys. , Univ. of Queensland, Brisbane) and Smith, E. K. (Nat'l. Bureau of Standards, Boulder,

Colo. ), A survey of the present knowledge of sporadic E ioni - zation. Journal of Atmospheric and Terrestrial Physics, London, 13(3/4) -.295-314, Feb. 1959. 2 figs. , tables, 142 refs.

DLC. Also issued as U. S. National Bureau of Standards,

NBS Report, No. 5564, May 15, 1958. DWB--This is a literature survey on sporadic E reflections characterized by one or more of these: random time of occurrence, partial transparency,

variation of penetration frequency or of a uniform apparent re- flection height. In a tabular form the survey includes the types

of zones, seasonal variation of Es, the diurnal and seasonal
338

variations of h'Es and the apparent vertical thickness of the

ionization, meteor-magnetic correlations and weather and

thunderstorm correlations, as well as airglow measurements

in the equatorial, temperate and auroral zones. Suggestions

on subjects deserving special experimental attention are added. -N. N.

A-1212 Thomas, J. O. ; Haselgrove, Jenifer and Robbins, Audrey

(all. Cavendish Lab. , Cambridge), The electron distribution

in the ionosphere over Slough. Pt. 1, Quiet days. Journal of

Atmospheric and Terrestrial Physics, London, 12(l):46-56f 1958. 5 figs. , 2 tables, 14 refs. , 6 eqs. DLC--A method of

calculating the distribution of electron density with height

from experimental virtual height-frequency records using an

electronic digital computer is outlined. The method assumes

that the N(h) curve is monotonically increasing but makes no

other a priori assumptions about the shape of the layer. It allows for the effect of the earth's magnetic field. The method

has been applied to a representative selection of h'(f) records

taken at Slough and the F2 layer results for the International

Quiet Days are presented and compared with previous work.

The height of maximum electron density in the F2 layer is

found to be considerably lower than previously supposed, particularly in the summer and equinox months. Results for the

Fl layer show that the peak of the layer (hmFl) is lower than

previously supposed and that the seasonal variation of hmFl

is the opposite to that expected for a Chapman layer. --Authors' abstract.

A-1213 Thomas, J. O. and Robbins, A. , The electron distribution in

the ionosphere over Slough, Pt. 2: Disturbed days. Journal of

Atmospheric and Terrestrial Physics, 13(1 -2): 131 -139, Dec.

1958. 6 figs., 9 refs.

A-1214 Thomas, J. O. and Robbins, Audrey (both, Cavendish Lab. , Cambridge), Ionospheric true height and M. U. F. calculations . Journal of Atmospheric and Terrestrial Physics, London, 12(1):

77-79, 1958. 2 tables, 9 refs. DLC--A recent investigation

resulted in new and more accurate determinations of the electron density distribution in the ionosphere over Slough, England (51. 5 N, 0. 5 W). It is now known that the larger deviations from the predicted values of MUF occur in summer and in

sunspot minimum years, the predicted MUF being too low. In

this paper the original MUF calculated for north-south transmission of the ordinary ray has been modified by taking into

account the effects of the earth's magnetic field. --N. N.
359

A-1215 Thomas, J. O. , The distribution of electrons in the ionosphere . Institute of Radio Engineers, N. Y. , Proceedings, 47(2):162-

175, Feb. 1959. 11 figs. , 4 tables, 92 refs. , 15 eqs. DLC

--This paper describes the methods now available for calculating the distribution of electrons in the ionosphere from observed virtual height-frequency records. Particular emphasis

is given to recently developed machine and manual methods

which make it practicable to produce electron distributions on

a rapid, routine basis. Attention is drawn to the importance

of these data for the physics of the ionosphere by quoting from

the results of some existing surveys. --Author's summary.

A-1216 Thomas, L. , Some measurements of horizontal movements in

region F2 using widely spaced observing stations. Journal of

Atmospheric and Terrestrial Physics, 14(1/2): 123-137, April

1959. 13 figs., 2 tables, 9 refs.

A-1217 Thompson, M. C. , Jr. and Waters, D. M. , Comparison of

phase difference and Doppler shift measurements for studying

ionospheric fine structure using earth satellites. Institute of

Radio Engineers, Proceedings, 46(12): 1960, Dec. 1958. 2

figs. , ref.

A-1218 The Threshold of Space: the Proceedings of the Conference on

Chemical Aeronomy, sponsored by the Geophysics Research

Directorate Air Force Cambridge Research Center, Air Research and Development Command, Cambridge, Mass. , June

25-28, 1956. Coordinated by Wentworth Institute. Ed. by

M. Zelikoff. pub. N. Y. , Pergamon Press, 1957. 342 p. figs.,

photos, refs. , eqs. DLC--About 200 scientists from many

countries participated in this conference held at Cambridge,

Mass. , on June 25-28, 1956. The 45 papers are presented

under 4 main heads: I. Atmos. photochemistry-earth and

Venus; II. Spectroscopy and photochemistry; III. Rocket

probing of the upper atmos. ; and IV. Phenomena produced by

hypersonic flight. Subjects concerning the airglow, ozone

formation, water vapor photolysis, sodium emissions, and

other aspects of photodissociation, recombination and chemical

luminescence in the high atmosphere as well as basis theoretical and laboratory studies are of interest to meteorologists and

aeronom.ists.--M. R.

A-1219 Titheridge, J. E. (Cavendish Lab. , Cambridge), Variations

in the direction of arrival of high-freguency radio waves.

Journal of Atmospheric and Terrestrial Physics, London, 13

(l/2):17-25, Dec. 1958. 2 figs. , 4 refs. , 9 eqs. DLC -A general relation is derived for determining the effect of a nonhorizontally uniform ionosphere on the propagation of short radio
360

waves. The deviations for linear and parabolic layers are evaluated and the results generalized to include an ionosphere

with several layers. Some experimental results showing large

diurnal changes in apparent bearing are discussed and shown to

be consistent with the foregoing theory. --Author's abstract.

A-1220 Titheridge, J. E. (Cavendish Lab. , Cambridge), The use of

the extraordinary ray in the analysis of ionospheric records.

Journal of Atmospheric and Terrestrial Physics, N. Y. , 17

(1/2): 110-125, Dec. 1959. 7 figs. , 3 tables, 4 refs. , 12 eqs.

DWB, DLC—When the ordinary ray trace on an h'(f) record is

used to compute an electron density profile (N(h) curve) assumptions have to be made about (a) the form which the h'(f) curve

would have taken at frequencies less than those actually employed, and (b) whether or not there is appreciable ionization

in the "valley" between the E and F layers. In this paper it is

shown how, by considering both the ordinary and the extraordinary ray traces on the h'(f) record, it is possible to avoid both

these assumptions to a considerable extent, and to deduce

something about the electron distribution in the lower ionosphere and in any valley. The method is applied to some ex- perimental records, and it is shown (a) that neglect of the lowlying ionization leads to an overestimate of the height of the

night-time F region ionization of about 20 km where the plasma

frequency is 2 Mc/s, and up to 15 km near the peak of the

layer, and (b) that the "valley" between the E and F layers is

small and nearly "full". --Author's abstract.

A-1221 Titheridge, J. E. (Cavendish Lab. , Cambridge), The calcula- tion of real and virtual heights of reflection in the ionosphere.

Journal of Atmospheric and Terrestrial Physics, h. Y. , 17

(l/2):96-109, Dec. 1959. 3 figs. , 3 tables, 8 refs. , 13 eqs.

DWB, DLC--A rapid and accurate manual method is described

by means of which the heights h corresponding to a given

series of electron densities N can be calculated from an ionogram which shows the h'(f) curve for the ordinary or extraordinary wave. The method makes allowance for the presence of

the earth's magnetic field. The virtual height is read only

once at about twenty frequencies, and the calculation of a complete N(h) curve requires less than 15 min. A slightly

modified method is described for use when very accurate re- sults are required, as, for example, in a study of the fine

structure of the E layer. The method makes use of a series of

coefficients which may be quickly calculated once and for all,

for a given place, with the aid of a desk calculating machine.

The law assumed for the shape of the segments used in the

analysis eliminates the necessity for the calculation and subsequent integration of the group refractive index in deriving

these coefficients. The coefficients for the extraordinary wave
361

are readily obtained by applying a correction to the "longitudinal" expression for the group refractive index. It is shown

how the same coefficients can be used in the inverse process

of deriving an h'(f) curve from a known N(h) curve. --Author's

abstract.

A-1222 Titheridge, J. E. (Cavendish Lab. , Cambridge), Ionization

below the night-time F layer. Journal of Atmospheric and Terrestrial Physics, N. Y. , 17(1/2): 126-133, Dec. 1959. 4 figs.,

2 refs. DWB, DLC--By making use of both the ordinary and

extraordinary ray traces on h'(f) records it is possible to estimate the amount and distribution of low-lying ionization, having plasma frequencies less than the lowest frequency recorded. By applying this method to h'(f) curves obtained at night,

it is possible to estimate the electron content of the E region,

even when its critical frequency is less than the lowest re- corded frequency. Results are given for Slough and Watheroo

for both summer and winter conditions, and for maximum and

minimum sunspot numbers. Near midnight the amount of ionization below the F region is equivalent to a constant density

of about 4000 electrons/cm^ extending down to a height of

130 km. The variation in the amount of this ionization near

sunset gives a constant effective recombination coefficient of

2 X 10"°cm3/sec. F layer heights calculated from the ordinary ray trace only are found to be too great by about 30 km at

f]tf = 1 Mc/s and 5 km at f jg = 6 Mc/s. --Author's abstract.

A-1223 Toman, Kurt (Cruft Lab. , Harvard Univ. ), Movement of the

F region. Journal of Geophysical Research, 60(l):57-70,

March 1955. 19 figs. , 10 refs. , 3 eqs. DWB--In the course

of a fixed-frequency ionospheric study, employing a pulsetriggered transmitter operating on 3. 5 Mc/s and three spaced

receivers, the transmission delay was continuously recorded.

Aside from a vertical-incidence transmission, two oblique

transmissions were thus available with 62 and 109 km as base

lines, the latter being correspondingly oriented in an approximate west-east and northwest-southeast direction. An analysis of the echoes from the F region was made for the period

between August 1952 and December 1953. Successive irregularities observed simultaneously on three records displayed

frequently consistent time -displacements. Assuming the midpoints of the transmissions to be characteristic and preferred

areas for the reflection of the h. f. -pulses, the time-displacements were interpreted as being due to a mechanical motion of

the F region. Direction and speed of this movement were thus

obtained, and semiannual and annual periods of these components became apparent. --Author's abstract.
362

A-1224 Toman, Kurt, New geometrical properties and their usefulness for ionospheric radio propagation. Institute of Radio

Engineers, Proceedings, 47(8): 1381-1382, Aug. 1959. 5 figs. , 9 refs.

A-1225 Tomner, J. and Sigvard A. , The experimental development of

traveling-wave tubes . G6teborg, Sweden. Chalmers Tekniska

Ho'gskola, Handlingar (Transactions), No. 67, 1948.

A-1226 Tonning, Andreas (Norwegian Defence Res. Estab. , Bergen),

Scattering of electromagnetic waves by an acoustic disturbance

in the atmosphere. Applied Scientific Research, Sec. B, 6

(6):401-421, 1957. 6 figs. , 3 refs. , eqs. DLC -The variations in density associated with an acoustic wave are shown

to influence the propagation of an electromagnetic wave. The

variation in electric permittivity of the atmosphere, caused by

an acoustic wave, is expressed by the power density of the

wave. Under the assumption that the acoustic waves are spherical, the scattered field at large distances is given in

terms of definite integrals which are evaluated by means of

the method of Stationary Phase. The limiting case of plane

acoustic waves is discussed, and two numerical examples

are given. --Author's abstract.

A-1227 Toshnival, C. R. , Radio studies of the upper atmosphere at

Allahabad. National Institute of Sciences of India, Proceedings, 3:337-354, 1937.

A-1228 Tsukada, Sohei (Central Radio Wave Observatory), Field intensity of WWV during geomagnetic disturbances. Japan. Science Council. Ionosphere Research Committee, Report of

Ionosphere in Japan, 5(4):197-198, 1951. DWB--Abstract of a

scientific study of two fluctuations in the field intensity of

the station WWV (Bureau of Standards, Wash. , D. C.) re- ceived at Hiraiso, Japan from July 1949 to Dec. 1950. Three

types of fluctuations and their diurnal and annual course are

briefly discussed. --A. A.

A-1229 Tufts College. Dept. of Electrical Engineering, Blossom IV-F; Aerobee Round 12; Development of VHF transmitter, power sup- ply, antenna, and insulating package for use with high altitude

balloons. Contract AF 19(122) -63, Progress Reports, 8 and 9,

March 15 to Sept. 15, 1951. 26 p. 45 figs, (many fold. ) DWB--Report covers details of preparation and flight of two

rockets: Aerobee Round 12 and Blossom IV -F, and improvements on data decoding facilities. Also the work done in

developing a balloon-borne transmitter, power supply, antenna

and thermal package which was produced for flight testing and

all of the wiring, details, photographs of parts of equipment,

test data, etc. are presented. --M. R.
333

A-1230 Tufts College. Dept. of Physics, Construction of a toroidlike discharge tube with a coannular magnetic field to reduce

loss of ions to the walls by diffusion. Contract AF 19(122)-

89, Quarterly Progress Report, No. 8, June 15, 1951. 31 p.

4 plates, 6 refs. DWB--Report describes equipment under construction at Tufts College in collaboration with the Geophysical Research Directorate, for studying electronic and ionic

processes in atmospheric gases, under conditions which simulate conditions in the ionosphere. A large copper toroid with

a magnetic field of 1500-3000 oersteds is described and practical as well as theoretical problems connected therewith are analyzed and illustrated. --M. R.

A-1231 Tuve, M. A. and Dahl, O. , A transmitter modulating device

for the study of the Kennelly-Heaviside layer by the echo method. Institute of Radio Engineers, Proceedings, 16(6): 794-798,

June 1928. 3 figs. , 3 refs. DLC--A method for modulating the

transmitter, based upon the sudden pulses of plate current oc- curring in an unbalanced multivibrator circuit, is described

briefly.

A-1232 Underhill, Bradford B. (Penna. State Col. , State College,

Penna. ), Ionospheric research at the Pennsylvania State College. U. S. Air Force. Cambridge Research Laboratories, Geophysical Research Papers, No. 7:143-153, Dec. 1950. 7 figs.

DWB--An account of the research work at the Radio Propagation Laboratory. The problem of frequencies below the broadcast band is the subject of primary interest. The diurnal

changes of height and absorption at vertical and oblique incidence at 150 Kc/sec are determined. --A. A.

A-1233 U. S. Army. Forces in the Pacific. Report on Japanese re- search on radio wave propagation. Tokyo, General Headquarters, U. S. Army Forces, Pacific Office of the Chief Signal

Officer, 1946. 2 v. (v. 1, 177+ p. ; v. 2, 133+ p. ) figs.

,

numerous tables. DLC--Vol. 1 consists of a survey and summaries of Japanese technical literature (most of it in Japanese)

written between 1926 and 1945. A list of the reports by source

and by subject precedes the actual summaries. The heading of

each summary contains the number, title, date of publication

and author of paper and classification as to type (field manual,

training manual, theoretical study, engineering study, etc. ). A historical survey of Japanese propagation work (p. 10-13)

and a summary of the more noteworthy features of the ionosphere as revealed by the Japanese observations (p. 18-19)are

also included in Vol. 1. Vol. 2 consists almost entirely of

tables summarizing Japanese ionospheric observations during

the period from June 1934 to Aug. 1945. --M.L. R.
364

A-1234 U. S. National Bureau of Standards. Central Radio Propagation Laboratory, Basic radio propagation predictions three

months in advance. Latest issue seen, No. 128, for July 1955,

pub. April 1955. Its CRFL, Series D. No. 128, almost entirely graphs. Price: annual, domestic, $1. 00 from U. S. Govt.

Print. Off. , Wash. 25, D. C. --Predictions are issued monthly

to provide information on lust sky-wave frequency over any

path at any time of day for average conditions in month in question 3 months in advance. Prediction charts are based on data

from 75 stations throughout the world and 12-months zenith sunspot numbers centered on month in question. Contour charts

of monthly median F2-zero-MUF, and F2-4000-MUF for each 3

zones, W, I. and E (shown on chart) into which the world is

divided by longitude, are presented along with a world-wide

contour chart of monthly median E-2000-MUF, contour chart of

median fEs and a chart showing % of time occurrence for Es2000-MUF in excess of 15 Mc. --M. R.

A-1235 U. S. National Bureau of Standards, Ionospheric radio propagation. Washington, D. C. , Government Printing Office,

June 25, 1948. 209 p. Numerous figs. , refs. and eqs. --The

basic theory of radio propagation is discussed and the current

knowledge of the subject is summed up. --W. N.

A-1236 U. S. National Bureau of Standards, N. B. S. Research in

radio propagation. Technical News Bulletin, 38(4):49-59,

April 1954. photos. DLC--A brief review of the work of the

Central Radio Propagation Laboratory, which has four main

divisions: (a) the Ionosphere Research Laboratory, whose investigations include solar rf radiation, upper atmospheric

winds, etc; (b) the Systems Research Laboratory, which is

concerned with tropospheric propagation and with research on

the best use of the frequency spectrum; (c) the Measurements

Standards Laboratory, which is responsible for the standardfrequency broadcasts from WWV and WWVH; (d) the propagation prediction services. --I. R. E. , Proceedings, No. 3018,

Nov. 1954.

A-1237 U. S. National Bureau of Standards. Central Radio Propagation Laboratory, Ionospheric data. Its Report CRPL-F81,

May 1951. 67 p. 84 figs. , 69 tables. DWB--Sources of ionospheric data in various parts of the world, which are regularly sent to the Central Radio Propagation Laboratory at Washington, D. C. and are coordinated with data obtained at Washington, are given. Terminology and symbols are defined.

Hourly data for Washington, D. C. , for April 1951 includes

all manner of ionospheric characteristics. Mean values of

these characteristics for each day are included for all available parts of the earth. Ionospheric storminess at Washington,
365

sunspot numbers at Zurich, coronal observations in Colorado

and New Mexico and much other data are included. --M. R.

A-1238 U. S. National Bureau of Standards. Central Radio Propagation Laboratory, Boulder, Colo., Ionospheric data. Its. CRPL-F127, March 1955. 95 p. 156 figs. , 106 + tables.

DWB--World wide sources of ionospheric data are listed; tables

give hourly data for Wash. , D. C. and 49 other places; storms,

SID's, radio propagation data, solar coronas, relative sunspot

data, solar flares, etc. Also presents data in graphic form for

50 stations throughout world, both observed and predicted 5

months previously for comparative purposes. Date of data

varies from Feb. -Dec. 1953 for Macquarie Island to Feb. 1955

for Wash. , D. C. --M. R.

A-1239 Utah. University. Dept. of Physics, Physical properties of

the upper atmosphere. Contract W19-122-ac-15, Progress Reports, Nos. 1-10, June 30, 1948-Dec. 5, 1951. 10 pieces,

diagrs. , graphs, eqs. DWB--Description of construction,

theory and performance of a 16 level step-voltage generator,

and a theoretical and experimental analysis of dispersive networks. A helical delay line possessing inductive dispersion

was constructed and delays were measured. Developmental

investigations of antennas for installation in tail fin of V-2

rocket, and receiving antenna for ground installation were

carried out. Further development on tests of antenna transmitters, circuits and cameras are indicated and illustrated in

last two reports. --M. R.

A-1240 Utah. University, Physical properties of the upper atmosphere . Contract W19-122-ac-15, Progress Report, No. 11-16, Dec. 31,

1950-March 31, 1952. 6 pieces, figs. , refs. DWB-Detailed

report on the development, design, construction and testing of

transmitter and antenna to be installed in a Blossom IV (V-2)

and an Aerobee rocket and of the recording receiver to be used

on the ground. Numerous diagrams are included. The purpose

was to determine the ion densities in the ionosphere and their

variations in time and space. This was to be done by pulse

transmissions through the ionosphere, mainly at frequencies

near the critical frequency of the E layer. It was also desired

to determine the effect of the ionosphere on pulse transmissions. Unfortunately, no data were obtained at the moment of

explosion during the firing of the rocket. --A. A.

A-1241 Utah. University, Physical properties of the upper atmosphere.

Contract W19-122-ac-15, Progress Report, No. 17, May 31,

1952, and Final Report for the Contract. Pub. July 30, 1952.

50 p. 8 figs. , table, refs. DWB--
366

An administrative report outlining the activities of the project which was mainly concerned with the development of airborne and ground equipment for the study of electromagnetic

waves at various altitudes by means of V-2 rockets and aero- bees. The method of attack was several times modified during the development of the work. Great care was taken in the

construction of an antenna adequate from both the transmission and aerodynamical points of view. The desired data about

ion density transmission constants, etc. were not obtained

since all the rockets misfired with the exception of one whose

beacon failed shortly after landing. Circuit schemes for the

developed equipment are included. —A. A.

A-1242 Utlaut, W. F. , Ionospheric effects due to nuclear explosions.

U. S. National Bureau of Standards, NBS Report, No. 6050,

April 30, 1959. 5 p. 2 figs., 5 refs. DWB (621.384

U585io) --Vertical-incidence ionograms of every 15 min routine

observations with a type C-2 ionosonde at the U. S. Nat. Bur.

of Standard's Field Station at Maui, Hawaii located approximately 1450 km NE of Johnston Island are presented. The discussion deals with the extreme disturbances on Aug. 1 and

again Aug. 12 coinciding with the high altitude nuclear explosions over Johnston Island. Complete radio fadeouts at several South Pacific circuits, abnormal magnetic perturbations,

and a rare tropical aurora (observed at Apia) are reported to

be effects of the blasts. --W. N.

A-1243 Uyeda, Hiroyuki; Miya, Kenichi and Kobayashi, Tsuneto

(Radio Wave Res. Lab. ), On the cause for unnatural distribution of occurrence of fEs and f min*'. Japan. Science Council.

Ionosphere Research Committee, Report of Ionosphere Research in Japan, 6(4):179-183, Dec. 1952. 4 figs., ref . , 3

eqs. DWBr

A-1244 Uyeda, H. ; Ogata, Y. ; Uchikura, K. ; Arima, Y. and Obayashi, H. , Three components of the field strength of the wave

reflected from the surface of the ionosphere: their level and

time variation. Japan. Radio Research Laboratories, Tokyo,

Journal, 2(8):143-161, April 1955. 10 figs. , refs., 40 eqs.

DWB--Sky waves reflected from the surface of the ionosphere

represent the different field strength varying with time for the

different components in level and form. Especially, the fading of the different components are not always of the same

phase or form and sometimes not of the same period. On the

other hand, the ionospheric observation has revealed that the

ionosphere flows with irregular surface, which produce the

variation of the same order as that of the fading period of E

and F echoes. In order to approach these observational re- sults, the field strength of the three components of the
357

received wave is estimated theoretically in the case where

the form of the reflecting surface of the ionosphere is mathematically defined and the velocity is assumed. A few ex- amples thereof are illustrated. Finally the formula to give

the fading period is derived in simple cases where two clouds

or a series thereof of the same form move in the same direction at the same velocity, keeping constantly a short interval

of time. The calculated result coincides well with the observed one, when they are assumed to be separated by the

distance of several kms and to have the velocity of about

0. 1 Kc/sec. --Authors' abstract.

A-1245 Uyeda, Hiroyuki; Ishida, Tadashi; Shibata, Kisashi; Mambo,

Masayoshi (all, Radio Res. Labs. ) and Ishida, Tadashi

(Kanto Radio Regulatory Board), On the reception of radio

waves from Sputnik I . Japan. Science Council. Ionosphere

Research Committee. Report of Ionosphere Research in Japan,

12(l):37-39, 1958. 2 figs. DWB, DLC-- A short note analyzing the satellite's orbits obtained from the data observed at

the Monitoring Division, Kuiki Radio Regulatory Bureau,

Ministry of Posts & Telecommunications and from the ephemeris given by the Smithsonian Astrophysical Observatory. The

regions of reception analyzed on the normal propagation by

F2 and Es layer reflections, and graphically represented, are divided into two regions. Region I corresponds to the region

in which the satellite is in flight lower than the height of

points of maximum electron density in the F2 layer, and region

II corresponds to the other region in which the satellite is in

flight higher than the height of points of maximum electron density in the F2 layer. An analysis of both regions is presented.

--I.S.

A-1246 Valverde, J. F. , Motions of large-scale travelling disturbances

determined from high-freguency backscatter and vertical incidence records . Stanford University, Electronics Research Laboratories, Contract AF 19(604) -1830, Scientific Report No. 1,

May 1958.

A-1247 Van Meter, D. (Pa. St. Coll. Radio Prop. Lab. ), Vertical

incidence eguivalent height versus time recording on 150 Kc/s.

Pennsylvania. State College. Radio Propagation Laboratory,

Contract AF 19(122)-44, Basic Ionospheric Research, Technical

Report, No. 12, June 15, 1950. 6 p. + 8 figs. , table, 2 refs.

Appendix: Tabulation of equivalent-height-versus-time data from

March 4, 1949 to Jan. 31, 1950. DWB--This report, a continuation of Technical Report, No. 8, presents equivalent-heightversus-time data taken at 150 Kc/s between March 4, 1949 and

Jan. 31, 1950. The body of the report is a tabulation, at 15-

minute intervals, of the equivalent heights obtained over the
338

above period. Included also are graphs and a table presenting: 1) Diurnal height variations for a few days at the end of

December 1949. 2) Monthly mean heights versus diurnal time,

3) Sunset and sunrise correlations, 4) Seasonal variations of

midnight and noon heights, 5) Comparison of storminess indices with CRPL indices and 6) Effects of sudden ionospheric

disturbances reported by CRPL. --Author's abstract.

A-1248 Vassy, Etienne (Prof. , Faculte des Science de Paris), Perturbation apportees par 1'atmosphere aux aides a la navigation.

(Disturbing effects of the atmosphere on navigation aids.

)

L'Onde Electrique, Paris, No. 295:379-383, Oct. 1951. 8 figs.,

13 refs. Abstracted from reprint. DWB—Disturbing effects on

radio communication are summarized. Author takes up first

the effect of the inclination of the ionized layers, of inhomogeneous ionization along the trajectories and of absorption and

diffusion in the ionosphere and then discusses disturbances

due to the troposphere (lateral refraction, conductivity and

diffusion phenomena). --A. A.

A-1249 Vassy, E. , La haute atmosphere. (The upper atmosphere.

)

Meteorologie, Paris, 4th Ser. , No. 35:185-194, July/Sept.

1954. 12 figs. DWB—Review of different indirect methods

for obtaining information on the high atmosphere (radio and

sound propagation, meteors, ozone, twilight airglow and auroral data), and direct methods used since the war (rockets)

to obtain density, temperature, chemical composition, ozone

and mass spectrometer data. Measurement of electrical properties by means of (a) UHF; (b) the U. S. Naval Research

Laboratory (NRL) method using two figures, 2. 34 Mc and

25. 6 Mc, or the sixth harmonic of the first, to determine

ionization at 80-160 km; (c) the Langmuir method which determines that no electrons exist below 70 km, although + and — ions occur at 60 km, and (d) Dopper method are described.

-M.R.

A-1250 Vassy, Etienne (Prof. Faculty of Sciences, Paris), Physique

de 1'atmosphere. tome I, Phenomenes d' emission dans 1'atmosphere. (Physics of the atmosphere, Vol. 1, Emission phenomena in the atmosphere. ) Paris, Gauthier-Villars, 1956.

338 p. numerous figs. --A most complete and up-to-date textbook, based on a lecture course given at the Faculty of Science

in Paris. The Introduction covers in detail the methods of investigating the upper atmosphere, both direct and indirect

(radiosonde, rockets, rockoons, etc. ), structure, physics,

chemistry, including latest data; (1) Aurora: history, forms,

distribution, frequency, periodicity, spectroscopy, theory,

application of results to study of upper atmosphere; (II) Night

airglow: measurement, color, spectroscopy, polarization,
3S9

time and space variations, correlation with other phenomena

(ionosphere, geomagnetic, C. R. , origin, etc.); (Ill) Twilight emission phenomena: oxygen, sodium, nitrogen and their

photoluminescence; (IV) Meteor trail luminescence: composition, spectra, mechanism of production, OPIK's theory, re- sults with respect to upper atmospheric winds and structure;

(V) Lightning and St. Elmo's fire, Sferics (observation, geographical distribution, structure, frequency, relation to meteorological situation). The work is full of illustrations of

equipment, representative data, graphs, etc. The literature

on each subject is thoroughly reviewed, but no bibliographic

references or citations are included. The only other similar

works are those by MITRA and KHRGIAN. -M. R.

A-1251 Vassy, Etienne, Radionaviqation et telequidaqe a qrande

distance. (Long distance radionavigation and radio-control.

)

Annates des Telecommunications, Paris, 14(9/10) :256-260,

Sept. /Oct. 1959. 5 figs. , 5 refs. , eqs. DLC.

A-1252 Veldekamp, J. and Scholte, J. G. J. , Maqnetische dubbele

brekinq in de ionosfeer. (Magnetic double refraction in the

ionosphere. ) (In: Netherlands. (K) Meteorologisch Instituut,

1854 Koninklijk Nederlands Meteoroloqisch Instituut, 1954.

'S-Gravenhage, 1954. p. 430-442. table, 15 refs. , 18 eqs.

DWB--Measurements of double and triple magnetic refraction

in the F2 layer above de Bilt ( $ = 52°6'. IN, A = 5°10'6E)

are compared with the calculated gyrofrequency. Formulas are derived for the reflection of ordinary and extraordinary rays

for vertical incidence in an electron-ion ionosphere, with allowance for collisions of electrons and ions. The observed

differences between the critical frequencies f z, f Q and f x

cannot be explained by the existence of ions, nor by the disturbing influence of electric currents in the ionosphere. It is

found that the deviation of the ray-paths in the geomagnetic

field may provide a sufficient explanation for the discrepancies.

--Authors' abstract.

A-1253 Venkateswarlu, P. and Satyanarayana, R. (both, Physics

Dep. , Sri Venkateswara Univ. , Tirupati), Fading of radio

waves. Current Science, Bangalore, 27(8) :296, Aug. 1958.

fig. , 2 refs. , eqs. DWB, DLC--A study of the fading of radio

waves has been conducted in the Ionospheric Laboratories of

the Physics Department of Sri Venkateswara University, Tirupati. Medium wave radio transmissions were observed from

Madras (distance - 110 km), Tiruchirapalli (distance - 320 km)

and Delhi (distance - 1700 km). Observations were made by

using a specially designed sensitive R-F amplifier - detector

unit. Details of the work are included in this letter to the

editor. --N. N.
370

A-1254 Vestine, E. H. (Carnegie Inst, of Wash. ), Observational

and theoretical aspects of magnetic and ionospheric storms.

National Academy of Sciences, Wash., D. C, Proceedings,

43(l):81-92, Jan. 1957. 7 figs., 20 refs. DLC--Some of the

characteristic features of magnetic and ionospheric storms

and the principal theories advanced for their interpretation are reviewed. The great magnetic storm of March 24, 1940

and concurrent ionospheric changes are discussed and the

latter is explained by the F region being "driven upward by

the electrostatic field directed from west to east within it",

following a separation of charge in the E region. The importance of electric field action upon the F region is confirmed by observations of F region behavior on magnetically

quiet days. --G.T.

A-1255 Vickers, M. D. (DSIR Radio Res. Station, Slough), The

calculation of the m. u. f. factor for a non-parabolic ionospheric layer. Journal of Atmospheric and Terrestrial Physics,

N. Y. , 17(1/2): 34-45, Dec. 1959. 4 figs. , 3 tables, 9 refs.

,

7 eqs. DWB, DLC--A method is described for calculating the

ray path of a radio wave through the ionosphere as represented

by an N(h) profile based on experimental data. A few such

paths are calculated and from these m. u. f. factors are obtained. These factors are compared with those which would

have been obtained had the existing methods of calculation

been used. In most cases the differences are less than 4%.

--Author's abstract.

A-1256 Vickers, M. D. , The effect of the Fl layer on the calculation of the height of the F2 layer. Journal of Atmospheric and

Terrestrial Physics, N Y., 16(1/2): 103-105, Oct. 1959. 2

figs., 3 refs., eq. DWB, DLC --An approximate relationship

between the estimated true height of the peak of the F2 layer

and that given by assuming a single layer having a parabolic

electron-density distribution is derived and compared with ex- perimental data. --Author's abstract.

A-1257 Vilenskii, I. M., K teorii vzaimodeistviia radiovoln v ionosfere. (The theory of radio wave interaction in the ionosphere. ) ZHurnal Eksperimental'noi i Teoreticheskoi Fiziki,

Moscow, 22(5): 544-561, May 1952. 2 tables, 9 refs. , 78 eqs.

DLC--A highly theoretical paper on the interaction of radio

waves containing a calculation of all high frequency terms of

such interferences. The theoretical analysis shows that in

case of radio wave interaction in the atmosphere there takes

place not only the phenomenon of cross modulation (the Luxemburg-Gorkii effect) but also the formation of "side (lateral)"

waves - waves with combination frequencies. In the course

of the analysis the author derives and discusses terms for
371

amplitudes of "lateral" waves. The role of collision of electrons with ions in various cases has also been investigated.

--A. M. P.

A-1258 Villard, O. G. and Peterson, A. M. , Scatter sounding: A

technique for study of the ionosphere at a distance. Institute

of radio Engineers, PGAP-3:186- , 1952. Also issued as:

Stanford University, Electronics Research Laboratories, Contract N6-onr-251 (07), Progress Report No. 54, Sept. 1952. -- Research has shown (1) that most oblique incidence backseattering occurs from the earth and not from the ionosphere. (2)

that the backscattering coefficient of the open sea is about the

same as of land (3) that relatively long pulses enormously increases the strength of the echoes. (4) that the time delay of

the leading edge of the scatter echo is a fair measure of

ground distance to the skip zone. On the basis of these,

scatter sounding may be used to determine muf for either Flayer or sporadic E transmission, and to plot at a distance

the growth of sporadic E clouds of ionization. Antenna rotation and ppi display shows at a glance which areas are open

to communication at a given time and frequency tests with

amateurs confirm expectations. Curves are presented to convert the oblique incidence time delay into skip distance.

A-1259 Villard, Oswald G. , Jr. and Peterson, Allen M. (Radio Prop.

Lab. , Stanford Univ. ), Scatter-soundinq: a new technique in

ionospheric research. Science, 116(3009): 221 -224, Aug. 29,

1952. 3 figs. , 6 refs. DLC- -Suggests that ionospheric investigations may be considerably extended in range from one

station by the use of echoes back-scattered from the ground

after reflection at oblique incidence at the E or F regions. It is found that pulse lengths about 10 times those commonly

used for vertical-incidence sounding received on conventional

communication equipment provide satisfactory ground backscattered echoes for ionospheric reflecting points as far away

as 1250 mis (F layer) or 600 mis (E layer). Possible applications are considered. --Physics Abstracts, No. 561, 1953.

A-1260 Villard, O. G. and Peterson, A. M. , Instantaneous prediction of radio transmission paths. QST, 36 ( 3 ) : 11-20, March

1952.- -- An experiment, conceived and performed by

amateurs, that represents not only a useful scientific contribution but also confirms a technique that has immediate applications in practical communication. By using the method discussed here it is possible to determine whether or not a band

is "open" in a given direction, and to what distance if so,

using familiar equipment with relatively simple modifications.

The determination can be made entirely at the transmitter, and

does not depend on other stations being "on the air.

"
372

A-1261 Villard, O. G. , Jr. ; Stein, Sidney and Yeh, K. C. (all,

Radio Propagation Lab. , Stanford Univ. , Calif. ), Studies of

trans equatorial ionospheric propagation by scatter-sounding

method. Journal of Geophysical Research, Wash., D. C,

62(3):399-412, Sept. 1957. 13 figs., 10 refs. Also: Silberstein, R. , (Comments on) O. G. Villard, Jr. ; Stein and K. C.

Yeh: Studies of transequatorial ionospheric propagation by the

scatter-sounding method. Ibid. , 62(4): 645-646, Dec. 1957.

3 foot-refs. DLC--Echoes of exceptionally long delay detected

by a HF radar located in the West Indies are interpreted as

ground backscatter propagated by two or more successive re- flections from the F region of the ionosphere, without intermediate ground reflection. Propagation of this sort is associated with tilts in the reflecting layers. Pronounced tilts are encountered regularly in equatorial regions; one occurs

almost daily at approximately 1900 local time over the geomagnetic equator; another occurs around noon in the vicinity

of the subsolar point. It is shown that tilt-supported propagation can take place at frequencies considerably in excess

of the MUF predicted in the usual way. It is believed that

these results may explain the reports by radio amateurs of

anomalous propagation between North and South America. -- Authors' abstract.

A-1262 Villard, O. G. , Jr. ; Stein, S. and Yeh, K. C, New evidence of anomalous transequatorial ionospheric propagation. Institute of Radio Engineers, Convention Record, Pt. 1:19-30,

March 1957.

A-1263 Vitkevich, V. V. and Kokurin, Iu. L. , Measurement of

phase and amplitude fluctuations of radio waves which have

traversed ionosphere. Radio Engineering and Electronics,

3(11) -.70-78, 1958. Transl. of original Russian in Radiotekhnika i Elektronika, 2(7):826-832, 1957.

A-1264 Wait, James R. , Induction by a horizontal oscillating magnetic dipole over a conducting homogeneous earth. American Geophysical Union, Transactions, 4(2): 185-188, April 1953.

table, 10 refs. , 22 eqs. MH-BH.

A-1265 Wait, James R. and Froese, Charlotte (Radio Physics Lab. Defence Res. Board, Ottawa), Reflection of a transient electro - magnetic wave at a conducting surface. Journal of Geophysical

Research, 60(1):97-103, March 1955. 5 figs. , 7 refs. , 25 eqs.

DWB--A solution is given for the reflection of a transient electromagnetic plane wave at oblique incidence from the plane interface of a dissipative medium. The inversion of the Laplace

transforms can only be carried out in closed form in special

cases. Series solutions are developed for the general case
373

and the numerical results are presented in graphical form.

Brief mention is made of the possible application of this solution to the reflection of a radio atmospheric at a sharply bounded ionosphere. --Authors' abstract.

A-1266 Wait, James R. , Radiation resistance of dipoles in an inter- face between two dielectrics. Canadian Journal of Physics,

Ottawa, 34(l):24-26, Jan. 1956. fig., 3 refs. , 11 eqs. DWB,

DLC--Exact expressions are derived for the radiation resistance of electric and magnetic dipoles located in the plane interface between two semi-infinite lossless dielectrics. --Author's abstract.

A-1267 Wait, James R. and Murphy, Anabeth (Nat'l. Bur. of Standards, Boulder, Colo. ), Multiple reflections between the earth

and the ionosphere in V.L. F. propagation. Geofisica Pura e Applicata, Milan, 35:61-72, Sept. /Dec. 1956. 8 figs. , 9

refs. , 15 eqs. DLC --Treating the ionosphere as a sharply

bounded ionized medium, sky wave field intensities are calculated by geometrical-opticdl methods for very low radio frequencies. The reflection coefficients are discussed in some

detail and the numerical data are compared with experiment.

--Authors' abstract.

A-1268 Wait, James R. (Nat'l. Bureau of Standards, Boulder, Colo.),

The attenuation vs. frequency characteristics VLF radio waves.

Institute of Radio Engineers, N. Y. , Proceedings, 45(6) :768-

771, June 1957. 10 figs. , 7 foot-refs. , eqs. DLC--The theoretical dependence on frequency of the attenuation of the wave

guide modes in VLF propagation is discussed in some detail.

It is indicated that most of the published experimental data

between 1 and 30 kc was compatible with the sharply bounded

model of the ionosphere with a reflecting height of about 70

km during the day and 90 km during the night. --Author's abstract.

A-1269 Wait, James R. and Perry, LorisB. (Nat. Bur. of Standards,

Boulder, Colo„ ), Calculations of ionospheric reflection coefficients at very low radio frequencies. Journal of Geophysical

Res., Wash., D. C. , 62(l):43-56, March 1957. 7 figs. , 9

refs. , 12 eqs. DLC. Also issued as U. S. National Bureau

of Standards, NBS Report, No. 3588, May 15, 1956. DWB--

A set of calculated curves are presented for the reflection

coefficients at a sharply bounded homogeneous ionized medium

with a superimposed magnetic field. The results are plotted

parametrically to permit general comparisons with experimental data. Both steady-state and transient cases are considered.

--Authors' abstract.
374

A-1270 Wait, James R. and Murphy, A. (both, Nat'l. Bureau of

Standards, Boulder, Colo. ), The geometrical optics of VLF

sky wave propagation. Institute of Radio Engineers, N. Y.

,

Proceedings, 45(6): 754-760, June 1957. 5 figs. , 3 tables,

10 foot-refs. , eqs. DLC--At distances not exceeding 1500

km, it is convenient to calculate the field strength of a VLF

transmitter by geometrical optics. In such computations, it

is usual to assume some equivalent height for the (ionospheric) reflecting layer with a reflection coefficient that

does not vary with angle of incidence. In the present paper,

the ionosphere is taken to be a homogeneous ionized medium

with a sharp lower boundary. The reflection coefficient,

which is a function of angle of incidence, is utilized to compute the strength of the single and multiple hop sky waves.

Combining these with the numerical results of the amplitude

and phase of the ground wave, the total field is obtained.

The theoretical fie Id -strength-vs -distance curves compare

favorably with the experimental data of Heritage for frequencies of 16. 6, 18. 6, 19. 8 kc over daytime paths in the

Pacific Ocean. Finally, diffraction by the earth's bulge of

the first hop sky wave is considered. This effect is important at ranges greater than 1200 km or so. --Authors' abstract.

A-1271 Wait, James R. (Nat'l. Bureau of Stands, Boulder, Colo. ), Introduction to the VLF papers. Institute of Radio Engineers,

N. Y. , Proceedings, 45(6): 739-740, June 1957. DLC-Thirteen

out of 47 papers presented at the Boulder, Colo, symposium on

VLF propagation Jan. 23-25, 1957 are presented in this issue

of the IRE. Most of them deal with noise from atmospherics

and with international standards for ionospheric propagation.

The introductory paper summarizes the subsequent papers. -- M.R.

A-1272 Wait, James R. (Nat'l. Bureau of Standards, Boulder, Colo.),

On the mode theory of V. L. F. ionospheric propagation. Geofisica Pura e Applicata, Rome, 37:103-115, 1957. 3 figs.

,

7 refs. , 47 eqs. DLC. Also issued with title: Mode theory

of VLF ionospheric propagation for finite ground conductivity. Institute of Radio Engineers, N. Y. Proceedings, 45(6): 760-

767, June 1957. 7 figs. , 14 foot-refs. , 42 eqs. DLC-The

space between the earth and the ionosphere is considered as

a wave guide with sharply bounded walls. Employing a representation in terms of spherical wave functions of complex

order, the field of a vertical dipole source is calculated for

very low frequencies. It is shown that the dominant mode for

16 kc is of order one and not zero as has been commonly supposed. Good agreement is obtained with the experimental re- sults of J. HERITAGE. -Author's abstract.
375

A-1273 Wait, J. R. and Howe, H. H. (both, Nafl. Bur. of Standards,

Boulder, Colo.), The waveguide mode theory of VLF ionospheric propagation. Institute of Radio Engineers, N. Y. , Proceedings, 45(1):95, Jan. 1957. 2 figs. , 5 refs. , 3 eqs. DLC

--The lower boundary (earth's surface) is a sharply bounded

isotropic medium, but the upper boundary (the ionosphere) is a diffuse anisotropic medium. However, for frequencies around

16 kc or less it can be assumed that both boundaries are sharp

and isotropic, so a simple solution of the wave guide mode

theory becomes possible under certain assumptions (verticallypolarized field at large ranges). Geometrical path calculations,

integrated for complex patterns or modes, and allowing for cur- vature of earth and conductivity of ground (a very important

factor) lead to attenuation rate curves and calculations (as ex- amples) of actual long distance propagation cases. The detailed calculations will be presented in a later paper. The dependence of sferic waveforms on geographic location is said

to be due to influence of ground conductivity on dominant mode.

--M.R.

A-1274 Wait, James R. (Nat'l. Bu. of Standards, Boulder, Colo.),

An extension to the mode theory of VLF ionospheric propagation. Journal of Geophysical Research, Wash., D. C. ,63(1):

125-135, March 1958. 9 figs. , 9 refs. , 10 eqs. DLC--The

wave-guide mode theory of VLF propagation for a sharplybounded homogeneous ionosphere is refined to include stratification at the lower edge of the ionosphere. The numerical

results for a two-layer model are discussed in detail. By

choosing the upper medium to have a conductivity with a factor

of 10 greater than the lower medium, the attenuation vs frequency characteristic of the model is consistent with experimental data from 1.0 to 20 kc. The effect of the finite thickness

of the E layer, important for frequencies less than 1. kc, is

treated by an ionospheric model which has a sharp lower edge

and an exponential taper to zero at greater heights. --Author's

abstract.

A-1275 Wait, J. R. , Propagation of very-low-frequency pulses to

great distances. U. S. National Bureau of Standards, Journal

of Research, 61(3): 187-203, Sept., 1958. 9 figs. , 9 refs.

A-1276 Wait, James R. (Nat. Bu. of Standards, Boulder, Colo. ), A study of VLF field strength data, both old and new. Geofisica Pura e Applicata, Milan, 41:73-85, 1958. 16 figs.

,

bibliog. p. 83-85, 2 eqs. DLC.

• A-1277 Wait, J. R. , Transmission and reflection of electromagnetic

waves in the presence of stratified media . U. S. National Bureau

of Standards, Journal of Research, 61(3): 205-232, Sept. 1958.

12 figs. , 15 refs.
376

A-1278 Wait, J. R. , Transmission loss curves for propagation at

very low radio frequencies. Institute of Radio Engineers,

Transactions, 6(2):58-61, Dec. 1958. 7 figs. , 9 refs.

A-1279 Wait, James R. and Conda, Alyce M. , Diffraction of electromagnetic waves by smooth obstacles for grazing angles.

U. S. National Bureau of Standards, Journal of Research, Sec.

D, 6(2):181-197, Sept. /Oct. 1959. 8 figs. , 26 refs. , 42 eqs.

DWB, DLC.

A-1280 Wait, James R. (Nat. Bureau of Standards, Boulder, Colo. ),

Diurnal change of ionospheric heights deduced from phase

velocity measurements at VLF. Institute of Radio Engineers,

N. Y. , Proceedings, 47(5, Pt. l):998f May 1959. 11 refs.

,

6 eqs. DWB--This is a review of some previous work by

Pierce and Crombie as reported in Nature, Vol. 177, pp. 178-

179, Jan. 28, 1956, on the variation of the phase of VLF

waves propagated over great distances. The present report

discusses the experimental data of Pierce and Crombie from

the viewpoint of the mode theory of VLF propagation. The

author objects to any analytical presentation which supports

the idea that ionospheric reflection coefficient remains the

same for day and night. --N. N.

A-1281 Wait, J. R. , Downcoming radio waves. Measurements of

characteristics. Electron Radio Engineers, 36(3): 106-107,

March 1959. fig. , 6 refs.

A-1282 Wait, James R. (Nat. Bureau of Stands. , Boulder, Colo.),

On the propagation of ELF radio waves and the influence of a nonhomogeneous ionosphere. Journal of Geophysical Research, Wash., D. C, 65(2): 597-600, Feb. 1960. 3 figs.

,

6 refs. , 8 eqs. DLC.

A-1283 Wait, James R. (Nat. Bu. of Stands. , Boulder, Colo. ), Terrestrial propagation of very-low-freguency radio waves, a

theoretical investigation. U. S. National Bureau of Standards, Journal of Research, Sec. D, 64(2): 153-204, Mar. /April

1960. 10 figs. , table, bibliog. p. 201-204, 13 eqs. DWB, DLC.

A-1284 Warwick, James W. , Scientific Report. No. 3 on Contract

AF 19(604) -1491. Climax, Colo. High Altitude Observatory

of the Univ. of Colorado, March 15, 1956. 9 p. 6 refs. , 19

eqs. DWB--At an early stage in the evolution of the research

program conducted under this contract, we decided to make the

measures of ionospheric absorption and refraction by means of

the type of phase-switching interferometer pioneered by Ryle,

at Cambridge, Eng. In the first report under the contract I assumed results on the signal-to-noise ratio for this equipment
377

from the published papers of Ryle who, however, did not discuss the detailed derivation of the results. In the present re- port I discuss problem of signal-to-noise ratio in the phaseswitching system, as well as the equipment's overall operation. --Author's abstract.

A-1285 Warwick, J. W. and Zirin, H. (both, High Altitude Obs.

,

Colorado Univ. ), Diurnal absorption in the D-region. Journal

of Atmospheric and Terrestrial Physics, London, 11(3/4): 187-

191, 1957. 2 figs. , 9 refs. , 7 eqs. DLC--We have analyzed

the diurnal variation of cosmic noise at a frequency of 18 Mc/s,

From these records we derive the electron density as a function

of local time and height in the D region. We also derive a oneparameter, exponential approximation to the vertical distribution of the ionizable constituent, nitric oxide. The electron

density curves fit those derived in different ways by other

groups. We predict that the recombination coefficient, within

the D region, is either constant, or increases with height. -- Authors' abstract.

A-1286 Warwick, James W. and Zirin, Harold, Research carried out

Oct. 1-Dec. 31. 1956 (at the High Altitude Observatory).

Colorado. Univ. High Altitude Observatory, Climax, Contract AF 19(604) -1491, Scientific Report, No. 6, April 1, 1957.

6 p. 2 figs. , 9 refs. , 7 eqs. DWB (M10. 535 C719s) -Construction of the 18 Mc/s wide-angle interferometer continues

through the report period. The antenna superstructures were

essentially completed, in unassembled form, receiver tests

on Ewen-Knight Radio Astronomy Receiver Model 1620 continued, but were not completed during the period. In view of

th© incomplete status of the equipment we decided to devote

time to analysis of the records from the IGY Radio Flare Detector, constructed at HAO with funds from another source.

The records show the intensity of cosmic noise (at 18 Mc/s)

vertically incident through the ionosphere. We are able to

derive from these records the march of electron density as a function of time of day and height in the D region. Surprisingly, we also can discuss the variation of recombination coefficient within a limited height range of the D region. The electron density curves fit, more or less, those derived in different ways by other groups. On the other hand, we predict that

the recombination coefficient either is constant with height

(in the D region), or increases upwards. --Authors' abstract.

A-1287 Warwick, James W. and Zirin, Harold, Research carried out

in the Report Period. Jan. 1. 1957-March 31. 1957. Colorado

Univ. High Altitude Observatory, Climax, Contract AF 19(604)-

1491, Scientific Report, No. 7, June 27, 1957. 5 p. 2 figs.

,

5 refs. , 11 eqs. DWB--
378

A technique is indicated for solving numerically the problem

of the variation, f(t) of the ionizing Lyman - d flux throughout

a sudden cosmic noise absorption (SCNA). The principal un- known in the solution is the recombination coefficient in the

D region. The observed discontinuity in the slope of the absorption at the outset of an SCNA demonstrates the existence

of a hundred-fold discontinuity in the ionizing flux at the beginning of a flare. This may be interpreted as a flash phase

in Lyman - d . Finally, the uncertainty in derivation of recombination coefficients from the time lag between flare maximum

in the optical spectrum, and maximum absorption in the D

region is noted. --Authors' abstract.

A-1288 Warwick, James W. , Measures of ionospheric absorption and

refraction at 18 megacycles/second. Colorado. Univ. High

Altitude Observatory, Contract AF 19(604) -1491, Final Report,

Dec- 15, 1958. 9 p. 2 figs. , 10 refs. DWB (M10. 535 C719s)

--Ionospheric absorption and refraction at a frequency of 18

Mc/s has been measured by means of the techniques of radio

astronomy. A description of the two experiment techniques

used are described in this report. --N. N.

A-1289 Watanabe, Tomiya (Geophysical Inst. Tohoku Univ. ), Studies

on P. S. C. after the Ashour-Price's model for the ionospheric

shielding effect. Tohoku Univ. , Science Reports, 5th Series,

Geophysics, 8(1):11-18, Nov. 1956. 4 figs. , table, 15 refs.

,

8 eqs. DWB, DLC --Theories of pulsational sudden commencements proposed up to the present are classified into two groups:

the intra-ionospheric origin theory and the extra-ionospheric

origin theory. The latter seems to be more favoured by the observational facts than the former. Especially, the daily behaviour of the horizontal disturbing vector anay be explained

fairly well by the ionospheric shielding effect for the original

extra-ionospheric magnetic field. --Author's abstract.

A-1290 Watanabe, Tomiya (Geophysical Inst. , Tohoku Univ. ), Electrodynamical behaviour and screening effect of the ionosphere.

Tohoku Univ. , Science Reports, 5th Series, Geophysics, 9(2):

81-98, Oct. 1957. 6 figs., 4 tables, 16 refs. , 59 eqs. DWB,

DLC--According to whether the fractional amount of the ionized

gas relative to the neutral gas is great or small, and to whether

the period concerned is short or long, an ionized gas containing neutral particles behaves as a hydromagnetic medium or as

a metal-like substance. For the period of the geomagnetic pulsation, from several seconds to a few minutes, the earth's ionized outer atmosphere behaves as a hydromagnetic medium; on

the other hand, the lower ionosphere shows a metal-like characteristic. Therefore, the Alfven wave caused in the outer atmosphere will be propagated downward, and in the lower
379

ionosphere, it will be transformed into an electromagnetic

wave, which will be propagated to the earth's surface and

will be observed as a geomagnetic pulsation. Because of the

metal-like behaviour, the lower ionosphere shows a screening

effect for the downwards -coming Alfven wave. If the ionospheric conductivity is sufficiently good, the screening effect

is so strong that the observed intensity of the geomagnetic

pulsation will be weakened considerably.

A-1291 Waterman, A. T. , Jr. ; Aden, A. L. and de Bettencourt, J. T. , A note on ionospheric radio-wave polarization. Journal of Geophysical Research, 55(l):53-56, March 1950.

A-1292 Waterman, A. T. , Jr. , Modulations imposed on a radio signal

by satellite motions. Stanford University, Electronics Research Laboratories, Contract AF 33(600) -27784, Progress Report No. 758-1, Aug. 29, 1958.

A-1293 Watson-Watt, Sir Robert A. , Directional observations of atmospherics 1916-1920. Philosophical Magazine, London, 45

(269) -.1010-1026, May 1923. 4 figs. , 2 tables. DLC-A statistical analysis of the 1300 bearings of atmospherics taken

between 1916-1920 by six British coastal finding stations.

A-1294 Watt, A. D. and Maxwell, E. L. , Measured statistical characteristics of VLF atmospheric radio noise. Institute of Radio

Engineers, N. Y. , Proceedings, 45(l):55-62, Jan. 1957. 15

figs., tables, 18 refs. , 4 eqs. DLC --Instrumentation for measuring the cumulative distribution of the amplitudes and spacings of pulses in the instantaneous envelope of the atmospheric

noise field strength is described. In general, the VLF atmospheric noise observed at 22 kc in a 1-kc band during the fall

of 1955 from 9 N to 71 N lat. was found to have a maximum

variation in average power level, including the effects of both

time and geographic location, of about 46 db. The dynamic

range of the instantaneous noise envelope, measured during a 20- to 30-min period of time, is defined to be the ratio of the

field strength exceeded 0. 0001% of the time to that exceeded

90% of such periods of time. This dynamic range in a 1-kc

band, for the 66 periods measured, varied from 59 to 102 db.

The average dynamic range in the Arctic was 68 db and in the

Tropics 81 db. The noise envelope at the low amplitude levels

is found to be Raleigh distributed, while at the higher levels

approaches a distribution having a much greater change in probability. In general, at higher levels the spacing between

pulses does not appear to be more random at temperate and

Arctic locations, but the noise pulses observed in the Tropics

appear to be more randomly spaced. When the bandwidth of

the receiver is reduced, the dynamic range approaches 21. 18
330

db, the value expected for the Raleigh distributed envelope

resulting from a thermal noise input. The bandwidth at which

this occurs will depend on the character of the atmospheric

noise at the time of observation, but appears from our measurements at 22 kc to be approximately 0. 2 cycle per sec. --Authors' abstract.

A-1295 Watt, A. D. ; Maxwell, E. L. and Whelan, E. H. , Low frequency propagation paths in Arctic areas. U. S. National

Bureau of Standards, Journal of Research, Sec. D, 63(1) :99-

112, July/Aug. 1959. 26 figs. , 3 tables, 25 refs. , 6 eqs.

DLC, DWB—The very low ground conductivities encountered in

Arctic areas, and the particular ionospheric conditions prevailing at high latitudes, can lead to rather unusual radiation

and propagation conditions. In order to determine the magnitude of these effects, field intensities from transmitters located in the Labrador and Greenland areas were measured both

on the surface of the earth and during several aircraft flights

over this area. The many factors involved in LF propagation

are considered and calculated field intensities compared with

experimental values. Under conditions where the initial portion of the propagation path is across icecap or permafrost,

the attenuation observed is very great, and when the propagation path extends out over sea water, the field intensity re- covery taking place after the coastline is crossed is very

marked. Estimates of skywave field intensity appear to agree

with the observed results provided the radiated field pattern is

suitably modified by the antenna outback factor which accounts

for the presence of a finitely conducting curved earth. These

vertical patterns based on work by Wait, along with the field

intensity flight data, indicate that the siting of low-frequency

stations several miles or more inland in Arctic regions may

cause a great increase in total transmission path loss. --Authors

9 abstract.

A-1296 Watts, J. M. and Brown, J. N. , Effects of ionosphere disturbances on low frequency variation. Journal of Geophysical Research, 56(3): 403-408, Sept. 1951. 8 figs. , 3 refs. MH-BH--

Observations made at the National Bureau of Standards from

May - Nov. 1950 of vertical incidence pulses from a vacuumtube transmitter at frequencies of 50, 100 and 160 kc show a uniform virtual height of about 90 km. Fluctuations on disturbed days are shown in 7 figures, where records of the reflections from 1 to 3 layers between 60 and 320 km height are re- produced, as made on 35 mm film. The explanation of these

variations, given for each case, shows that ionospheric storms

have sudden and marked effects in nighttime reflection from the

E layer. Daytime effects are more limited. Close correlation

is shown between % disturbed operating time and normal magnetic K indices, (for Cheltenham) at night. --M.R.
331

A-1297 Watts, J. M. (Central Radio Prop. Lab. , Wash. , D. C. ), A note on the polarization of low frequency ionosphere echoes.

Journal of Geophysical Research, 57(2): 287-289, June 1952.

3 refs. MH-BH--The use of a low frequency pulse transmitter

in conjunction with antennas for emitting waves of nearly circular polarization gave additional information on the state of

polarization of vertically incident reflected waves from the

ionosphere. Automatic switching of sense of rotation provided

a means of "tagging" portions of complicated h-t recorder traces

if the amplitude response varied with incident wave polarization sense. --Author's abstract.

A-1298 Watts, J. M. (Central Radio Propagation Lab. , Nat'l. Bureau

of Standards, Wash. , D. C. ), Oblique incidence propagation

at 300 kc using the pulse technique. Journal of Geophysical

Research, 57(4):487-498, Dec. 1952. 7 figs. , 6 refs. MH-BH

--The results of an oblique incidence pulse experiment at 300

kc, using a path length of 1185 km over sea-water, are presented. These consist of median time delays of sky wave vs

surface wave for March, April and May, 1951, together with

pulse envelope photographs of typical pulse groups, continuous film recordings of surface- and sky-wave pulses, a plot of

sunrise transition times, and a discussion of the sunrise conditions. --Author's abstract.

A-1299 Watts, J. M. and Brown, J. N. , Some results of sweep-frequency investigation in the low frequency band. Journal of

Geophysical Research, 59(l):71-86, March 1954. 13 figs.

,

10 refs. MH-BH--Sweep-frequency techniques, long in use in

high-frequency ionospheric research, have been used recently

in low frequency research at the U. S. National Bureau of Standards. The discovery of a nighttime layer between the E and F

layers, which is erratic in appearance, but which seems to

have continuity with the daytime E layer during sunset, is an- nounced. Trace characteristic of magneto-ionic splitting are exhibited for the new layer and also for the low-level E layer.

Polarization and virtual height records of F layer at night are shown and the effects of ionosphere storms on E and F regions

are demonstrated. Daytime reflections have been recorded

from three distinct E region boundaries, each of which appears

to be quite sharp in ion gradient. These extend from about 70

km to over 100 km in virtual height. Several recordings of turbulent conditions in the lower levels of the daytime E region

are shown. --Authors' abstract.

A-1300 Watts, J. M. (Nat'l. Bur. of Stand. , Boulder, Colo.), Audio- frequency electromagnetic hiss recorded at Boulder in 1956.

Geofisica Pura e Applicata, Rome, 37:169-173, 1957. 4 figs.

,

3 refs. DLC--
382

Hissing noise is very frequently heard on receivers used for

detecting whistlers during geomagnetic disturbances. This

phenomenon may be associated with the "dawn chorus" or whistlers, but is distinct from either and also from sferics.

The energy is concentrated in narrow band widths that fluctuate, giving a surging rather than a steady hissing effect.

Relative amplitude of the hiss, compared with the geomagnetic field records, is shown graphically. The hissing begins

about 8 hrs after the rapid commencement of the storm. Records show the peak energy of the hiss was near 3 kc. Variations in spectra of hiss frequency are illustrated by numerous reproduced records from March-Dec. 1956, hissing was

heard on 9 out of 15 major magnetic storms recorded at Boulder,

Colo. , at Sunset Field Station. —M. R.

A-1301 Watts, J. M. (Nat. Bur. of Stand. , Boulder, Colo. ), Complete

night of vertical-incidence ionosphere soundings covering frequency range from 50 Kc/s to 25 Mc/s. Journal of Geophysical Research, Wash., D. C. , 62(3): 484-485, Sept. 1957.

photo. DLC--A presentation of ionospheric sounding records

for each half hour from 1730 MST to 0730 MST for one complete

night, covering the entire range of frequencies from <T 100 Kc

to > 25 Mc/s. The composite records are made by joining a

2 Mc/s record made with a Model C-4 recorder at Boulder to a simultaneous record made with a low frequency recorder at

Sunset Field Station 15 miles away. Series shows sunset and

sunrise effects during moderately disturbed conditions. --M. R.

A-1302 Watts, J. M. (Nat. Bur. of Stand. , Boulder, Colo. ), An observation of audio-frequency electromagnetic noise during a period of solar disturbance. Journal of Geophysical Research,

Wash., D. C, 62(2): 199-206, June 1957. 5 figs. , 6 refs.

DLC.

A-1303 Watts, J. M. (Nat'l. Bur. of Stands. , Boulder, Colo.), The

interpretation of night-time low-freguency ionograms. Journal

of Geophysical Research, Wash., D. C, 63(4, Pt. l):717-726,

Dec. 1958. 6 figs. , 4 refs. , eqs. DWB, DLC-Two types of

retardation of the extraordinary ray on passing through a region

whose critical frequency is below the gyro-frequency are discussed. On a sweep-frequency basis, one is observed near the

critical frequency of the ordinary ray and the other appears near

the gyro-frequency. Observations of either require near transparency of the lower E region during the night, but information

as to the total number and distribution of electrons below the

F layer can be deduced from them. --Author's abstract.
383

A-1304 Watts, J. M. (Nat. Bu. of Stands. , Boulder, Colo. ), Direction findings on whistlers. Journal of Geophysical Research, Wash., D. C, 64(11): 2029-2030, Nov. 1959. photo.

DLC.

A-1305 Watts, J. M. (Nat. Bu. of Stands., Boulder Laboratories),

Interpretation of some features of low -frequency ionograms.

Journal of Atmospheric and Terrestrial Physics, London, 15

(1/2): 73-76, Sept. 1959. 5 figs. , 3 refs. DLC.

A-1306 Waynick, A. H. , The conference on ionospheric research

(held at Pennsylvania State College. . . June 27-28-29. 1949).

Journal of Geophysical Research, 54(3) -.281-288, Sept. 1949.

MH-BH—Summaries of 12 papers mostly on effect of ionosphere

layers on waves of various lengths. Papers indexed separately. Symposia summarized by A. H. WAYNICK include: Longwave propagation; Physical bases of Appleton-Hartree dispersion equation; Auroral region studies; Ionospheric absorption,

theory and measurement. --C. E. P. B.

A-1307 Waynick, A. H. , Summary of (Conference on Ionospheric Re- search, Pennsylvania State College, June 1949). U. S. Air

Force. Cambridge Research Labs. , Geophysical Research

Papers, 7:167-174, Dec. 1950.-- Fourteen recommendations of

former conferences for its further research are compared with

the results of the conference in June 1949. Summarized symposia of five important problems of ionospheric research are given.

A-1308 Waynick, A. H. (Penna. St. Coll., Pa.), Studies of the ionosphere using very long wave pulse techniques . International

Council of Scientific Unions. Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 161-

165. DWB--Results of vertical incidence equipment height

records made at Perm. State College from March 1949-April

1950 and vertical incidence absorption records with semi-automatic equipment since April 1950, and vertical incidence polarization measurements since late spring 1950, are summarized and equipment described. --M. R.

A-1309 Waynick, Arthur H. (Ionosphere Res. Lab. , Penn. State

Univ. , University Pk. , Pa. ), The present state of knowledge

concerning the lower ionosphere. Institute of Radio Engineers,

N. Y., Proceedings, 45(6): 741 -749, June 1957. table, 78 footrefs. DLC. Also issued as Pennsylvania. State Univ. Ionosphere Research Lab. , Contract AF 19(604) -1304, Scientific

Report, No. 90, Feb. 1, 1957. 34 p. table, 78 refs. --In this

paper an attempt is made to summarize the current state of

knowledge concerning the lower ionosphere. This includes at
384

D and lower E region heights: electron density as functions of

height and time, dissipative processes, the possible atmospheric constituents involved and their distributions, physical

parameters to be considered, and solar radiation and other factors relevant in the formation of this portion of the ionosphere.

Where possible, comparisons between theory and experiment

are made. —Author's abstract.

A-1310 Waynick, A. H. , Ionospheric research. Pennsylvania. State

Univ. Ionosphere Research Laboratory, Contract AF 19(604)-

1304, Final Report for Period Jan. 1, 1955 to Aug. 31, 1958.

Sept. 30, 1958. 51 p. eqs. —The present statement of work

is on the theoretical and experimental investigations on the

physics, dynamics and general properties of the ionic layers

of the earth's atmosphere. Problems related to ionospheric

phenomena, electromagnetic studies, solar and high atmosphere physics as well as equipment developments are discussed. The report concludes with an appendix that contains

abstracts of the 36 Scientific Reports issued during Jan. 1,

1955 to Aug. 31, 1958, and a list of over 200 papers and re- ports issued or published in journals read at meetings, etc.

,

which emanated from this project. —N. N.

A-1311 Webster, H. C. (Physics Dept. , Univ. Queensland, Brisbane),

A study of "spread-F" ionospheric echoes at night at Brisbane,

Pt. 4. Range spreading. Australian Journal of Physics, Melbourne, ll(3):322-337, Sept. 1958. 10 figs. , 8refs., 20 eqs.

DLC--In the course of investigations of satellite echoes from

the F region of the ionosphere, it was noted that F and Es

traces recorded at night, on h't equipment at frequencies well

below vertical, are broader than anticipated and tend to change

in a characteristic manner as the gain of the receiver is lowered. In this paper, a quantitative explanation of these phenomena is elaborated, based on the postulate of a "rough" ionosphere. This theory leads to a method whereby, from the

swept-gain h't records, estimates of roughness index can be

formed. These estimates compare satisfactorily, on a statistical basis, with estimates by other methods. The theory is

extended to the case of multiple-hop reflections, and to the

satellite traces; general agreement with experiment is found.

Evidence is presented that the ionosphere appears rougher

when transmitter and receiver are adjacent than when they are widely separated, and a tentative explanation is suggested.

From the roughness indices, the relative intensities of Z- and

0- mode F echoes for Brisbane are computed and the rare appearance of Z-traces on Brisbane records is satisfactorily ex- plained. --Author's abstract.
385

A- 1312 Weekes, K. and Stuart, R. D. , The ionospheric propagation

of radio waves with frequencies near 100 kc/s over distances

up to 1000 km. Institution of Electrical Engineers, Proceedings,

Pt. 4, 99(2):38-46, April 1952. 13 figs. , 4 tables, 11 refs.

DLC—The first paper described steep incidence and this paper

is an extension of the observations and discusses oblique incidence. The results show: (1) Height of reflection for distances greater than 400 km is about 70 km at midday in summer

and no definite variation of height with frequency was observed.

(2) The reflection coefficient increased steadily with distance

(0. 02 at 300 km to 0. 09 at 800 km) for a frequency of 70 kc/s;

lesser on higher frequencies. The winter reflection coefficient

roughly doubled the summer values. Except for that during

sudden disturbances, the amplitude of the sky wave increases

by a factor up to 5, and sometimes reaches the night values

(distance 850-900 km from the sender). The observations to a great extent correlate well with those discussed in the first

paper. --W. N.

A-1313 Weekes, K. (Cavendish Labs. , Cambridge), On the interpre - tation of the Doppler effect from senders in an artificial satellite . Journal of Atmospheric and Terrestrial Physics, N. Y.

,

12(4):335-338, 1958. fig., 2 refs. , 6 eqs. DLC--In 1929

MIRICK and HENTSCHEL observed beats in the signal strength

of radio waves from an aircraft at a fixed receiver. They interpreted these beats as interference effects between a direct ray

and a ray reflected from the ionosphere and deduced a height

for the effective reflecting layer. APPLETON (1930) compared

this method of estimating the height of the ionosphere with

those previously used. He showed that the beat could be re- garded as a Doppler beat between the rays arriving by the two

paths and that, as the height of the aircraft was negligible

compared to that of the ionosphere, the experiment measured

directly sin i where c is the angle of incidence of the ray on

the reflecting layer. This problem is very similar to that of

the observation of the Doppler effect from a sender in an artificial satellite and it is of interest to enquire whether the Doppler shift depends simply on sin i in this case when the sender

is in the ionized medium and the distances are such that allowance must be made for the curvature of the earth. --Author's

abstract.

A-1314 Weekes, K. (Cavendish Lab. , Cambridge), Drift of an ionized

layer in the presence of the geomagnetic field . (In: Polar Atmospheric Symposium, Oslo, July 2-3, 1956, Proceedings, Pt. 2,

Ionospheric Section, N. Y. , Pergamon Press, 1958. p. 12-19.

4 figs. , 7 refs. ) Also issued in Journal of Atmospheric and

Terrestrial Physics, London, Special Supplement, Pt. 2, 1957,

pub. 1958. p. 12-1 DWB, DLC--
386

This article shows that while the neutral air moves there is

both a current flow as well as a drift of the ionization in the

plasma which is superposed on the original air movement.

The irregularity that is observed in this layer may be moved

by wind in the neutral gas or by an applied electric field

herein discussed. When a comparison of the relative efficiencies of these two cases is to be made we also have to

compare the velocities of drift resulting from a wind of velocity C and from an electric field E = C B, where B is the

steady magnetic field. The velocity components of such an

irregular drift are relative to the air. If there is a wind C , contributing El = C B to E the velocity relative to any fixed

observer is (V - C ). It is shown that in some areas of the

F layer drifts are caused by electric fields due to polarization changes; in the E region they are caused both by wind

and by electrical field changes; while in the D region wind

alone is the effective factor. --N. N.

A-1315 Weekes, K. (Cavendish Lab. , Cambridge, England), Evidence about Es from N(h) profiles. AGARDograph, Paris,

No. 34:149, Sept. 1958. DWB (629. 1323 N864a)--Two points

are made in this note, one about the classification of Es types

by virtual heights, and the other about the shape of the E layer

in the presence of Es. It is found that the virtual height of the

Es trace may be determined mainly by the gradient of the N(h)

curve near the Es, and not by the actual height of the Es layer.

On one occasion it was observed that, during an Es condition, a distortion was observed in the E layer which might explain

the Es condition by a redistribution process. --Author's abstract.

A-1316 Weiffenbach, George C. , Measurement of the Doppler shift of

radio transmissions from satellites. Institute of Radio Engineers, Proceedings, 48(4): 750-754, April 1960. 6 figs. , refs. , eq. DLC--This paper describes a receiving station network

that was designed to produce Doppler data for use in a satellite Doppler navigation system. As a result of practical exigencies, this equipment is not optimum for its intended purpose, and a continuous effort is being maintained to improve

the system. Current and projected changes are described

briefly. Some experimental results obtained with the present

system are presented. --Author's abstract.

A-1317 Weisbrod, S. and Colin, L. , Refraction ov very high frequency

radio signals at ionospheric heights. Nature, London, 184

(4680):119, July 11, 1959. figs., 2 refs. Also issued in

Institute of Radio Engineers, Transactions, AP-8(1):107, Jan.

1960.
387

A-1318 Weisbrod, 3. and Anderson, L. J. , Simple methods for computing tropospheric and ionospheric refractive effects on radio

waves. Institute of Radio Engineers, Proceedings, 47(10):

1770- , Oct. 1959.

A-1319 Wells, H. W. ; Watts, J. M. and George, D. E. , Detection

of rapidly moving ionospheric clouds . Physical Review, 69

(9*10): 540-541, May 1946. --Observations were made during the

magnetic storm of March 25 and 26, 1946, with a new panoramic recording technique that enables the frequency range 1. 5

to 20 megacycles to be swept in a time adjustable from 5 to

30 seconds. The ionospheric clouds were observed to move

in from 800 to 900 kilometers down to 300 to 400 kilometers

at a rate of 1 to 2 kilometers, and sometimes to move out

again at a similar rate. 'The principal effects of influx of the

clouds are: (1) sudden changes in F layer ionization; (2) rapid

changes in F layer heights indicating turbulence which is often

progressive from high to low heights and from high to low frequencies; (3) rapid fluctuations of echoes at the lower frequencies with occasional temporary disappearance indicating

high absorption. The clouds are provisionally attributed to

corpuscular ionization during magnetic disturbances, indicating a corpuscular contribution to F layer ionization. An inaccurate account of these observations was noted in 2889 of

October.

A-1320 Wells, H. W. , Spot-freguency ionospheric recording: a combination of sweep- and fixed-freguency technigues. Journal of

Geophysical Research, 56(4):613-615, Dec. 1951. 2 figs.

DLC--The panoramic high-speed ionospheric records are quite

useful for the study of ionospheric irregularities, travelling

disturbances and eclipse observations, but produce such tremendous amounts of data (3, 600 in 10 sec) that nobody can

keep up with the evaluation of the results. The author proposes a simplified sampling technique which gives a complete

tabulation of virtual ionosphere heights with a minimum of scaling effort. --A. A.

A-1321 Wells, H. W. (Carnegie Inst, of Wash. , Wash., D. C. ),

F-scatter at Huancayo, Peru, and relation to radio star scintil - lations . Journal of Geophysical Research, 59(2): 273-277, June

1954. 2 figs. , 6 refs. MH-BH--The scattering of radio waves

by the F region of the ionosphere at an equatorial location

(Huancayo, Peru) was discussed by BOOKER and WELLS (1938).

Subsequent analysis reveals pronouncedly diurnal, seasonal,

and annual characteristics. It is fundamentally a night-time

event, with greatest frequency of occurrence in the period from

four hours before midnight to four hours after midnight. The

scattering is most prevalent during seasons when the sun is
388

overhead and is infrequently observed during May, June, July,

and August (local winter) when the noon solar zenith angle becomes as great as 35 . The relative total annual occurrence

of F region scatter for the period 1938 through 1945 shows low

values during 1941-1942, followed by a rapid increase through

1946, which is not closely related to solar activity. The

diurnal properties of F scatter closely correspond to reported

characteristics of radio star scintillations with peak activity

around midnight. However, the annual or seasonal properties

are not in simple agreement. --Author's abstract.

A-1322 Wells, H. W. (Carnegie Inst, of Wash. , Dept. of Terrestrial

Magn. ), Large-scale movements of the layers. (In: Polar Atmosphere Symposium, Oslo, July 2-8, 1956, Proceedings, Pt. 2,

Ionospheric Section, N. Y. Pergamon Press, 1958. p. 33-40.

12 figs.) Also issued in Journal of Atmospheric and Terrestrial Physics, London, Special Supplement, Pt. 2, 1957, pub.

1958, p. 33-40. DWB, DLC--Various charts and figures are presented to illustrate the typical cloudlike surge in foF2 and

its variations. The back-scatter records at different points

near Washington, D. C. are included as well as the graphs of

critical frequencies for various stations spaced 150-200 km or more in Maryland, Virginia and West Virginia. The results of

this work are based on analysis of both the ordinary and the

extraordinary wave components as shown on the velocity-vector

wavelength component charts, Dec. 1952. Arrows show the

magnitude and direction of drift motions at each significant

height. --N. N.

A-1323 Wells, W. B. , Upper atmosphere studies by means of lowfreguency electromagnetic waves. U. S. Navy. Electronics

Laboratory, San Diego, Calif. , Report 311, Dec. 9, 1953.

72 p. 32 figs. , 2 tables. DWB--£lectromagnetic measurements

were conducted on two consecutive days of each month from

April 1950 through February 1951, except May and November,

to study the propagation properties of the upper atmosphere.

The receiving site was located near Gila Bend, Arizona.

Photographic records of oscilloscope traces (A-scan) were

taken of signals from distant lightning discharges (sferics)

and of echoes from pulse soundings on 196 kc at vertical incidence. Sferics (of frequencies between approximately 5 and

20 kc) at oblique incidence are refracted from heights of 82 to

92 km at night. Pulse soundings at vertical incidence, on a frequency of 196 kc, indicated average nighttime virtual heights of reflection between 76 and 120 km. No significant cor- relation was found between the data obtained on the electromagnetic studies and those on acoustic studies conducted in

the same area. --Author's abstract.
389

A-1324 Westfold, K. C. , The interpretation of the magneto-ionic

theory. Journal of Atmospheric and Terrestrial Physics, 1(3):

152-186, 1951. --Studies particular approximate solutions of

the quadratic equation determining complex refractive index

and polarization. For the case of collision-frequency small

compared with the wave frequency, presents a set of curves

from which the mathematical behavior of the complex dielectric constant and polarization can be obtained. From these

curves other curves are derived depicting the behavior of re- fractive index and absorption coefficient under physical conditions. Also uses approximations that gyro-frequency is

small or large compared with the wave frequency, and collision frequency large compared with the wave frequency. Some

discussion is given of the application of the magneto-ionic

equations to the solar atmosphere as well as to the ionosphere.

--L.A. M.

A-1325 Whale, H. A. and Stanley, J. P. , Group and phase velocities from the magneto-ionic theory. Journal of Atmospheric and

Terrestrial Physics, l(2):82-94, 1950. 11 figs. , 11 refs. , 19

eqs. MH-BH--Calculations of group velocity are made at Cambridge with an electronic computer (EPSAC) and curves presented to show visually the behavior of radio waves passing

through an ionized medium, under a variety of conditions. The

ordinary No-field case, the ordinary Component and the Extraordinary Component are considered separately. Three dimensional models are drawn to show the dependence of curves on

the value of y. The effect of varying direction of propagation

angle and of wave length is also shown. --M. R.

A-1326 Whale, H. A. , Determination of electron densities in the ionosphere from experimental (h'» f) curves. Journal of Atmosphere and Terrestrial Physics, l(4):244-253, 1951. 5 figs.,

10 refs. , 12 eqs. DWB--It is shown how a differential analyzer can be used to facilitate the calculation of ionospheric

distributions of electron density directly from observed (h' f f) curves by previously known methods. It is pointed out that

the simple method, in which the earth's magnetic field is

neglected, leads to inacceptable results. A modified method

by which the effect of the earth's field can be approximately

allowed for is described and it is shown that, when this method is employed, feasible results are obtained. --Author's abstract.

A-1327 Whale, H. A. , Fine structure of the ionospheric region E.

Journal of Atmospheric and Terrestrial Physics, l(4):233-243,

1951. 6 figs. , 12 refs. DWB--Deals with the vertical distribution of electron density of the E region and the way in which

this distribution changes with time. This descriptive
390

investigation is based on a series of accurate (h 1 , f) records

obtained by employing two oscillators. The experimental re- sults are presented in curves and compared with theoretical

curves for various model ionospheres. --W. N.

A-1328 Whale, H. A. , Widespread diurnal variations of effective

slope of the ionosphere. Nature, London, 175(4445): 77-78,

Jan. 8, 1955. fig. , ref . , eq. DWB—Bearing and elevation of

radio signals from Fiji and Brisbane, received at Seagrave,

Auckland, are used to determine daytime diurnal variation of

the effective N - S and E - W slopes of the ionosphere. -- Co E. P. B.

A-1329 Whale, H. A. , An estimate of the size of the antipodal area

in short-wave radio propagation. Journal of Atmospheric and

Terrestrial Physics, 9(2/3): 159-161, Aug. /Sept. 1956. fig.,

ref. DWB.

A-1330 Whale, H. A. , Effective tilts of the ionosphere at places

about 1000 km apart. Physical Society of London, Proceedings,

Ser. B, 69(3) :301 -310, March 1, 1956. 8 figs. , 5 refs. , eqs.

DWB—Observations of bearing and elevation of signals received at Auckland, N. Z. , from Fiji (9315 Kc/s, distance 2000

km) and Brisbane (9660 Kc/s, 2250 kmT'are sometimes consistent with the existence during the daytime of effective ionospheric tilts which are similar at places more than 1000 km

apart. These tilts are of the order of half a degree and are in

opposite directions during the morning and the afternoon. They

may correspond to actual tilts of a uniform ionosphere or be

due to horizontal gradients of electron density. "--From author's

abstract.

A-1331 Whale, H. A. (Seagrove Radio Res. Sta. , New Zealand) and

Delves, L. M. (Wadham College, Oxford), Some relations be- tween the bearing and amplitude of a fading radio wave. Journal of Atmospheric and Terrestrial Physics, London, 13(1/2):

72-85, Dec. 1958. 7 figs. , 8 refs. , 16 eqs. DLC.

A-1332 Whale, H. A. (Seagrove Radio Res. Station, New Zealand),

The effects of ionospheric irregularities and the auroral zone

on the bearings of short-wave radio signals. Journal of Atmospheric and Terrestrial Physics, London, 13(3/4): 258-270, Feb.

1959. 8 figs. , 12 refs. , 5 eqs. DLC.

A-1333 Wheeldon, A. J. , The IXth plenary assembly of C. C. I. R.

Point to Point Telecommunications, 4(1): 12-16, Oct. 1959.

ref. DLC --The activities of the several study groups of the

International Radio Consultative Committee (C. C. I. R. ) as

observed during the 9th plenary assembly at Los Angeles in
391

1959 are briefly reviewed. The some 300 delegates represented 36 countries. English language, rather than the official French language tends to become the working language

of the assemblies. --W. N.

A-1334 Wheelon, A. D. (Ramo-Wooldridge Corp. , Los Angeles,

Calif. ), Note on scatter propagation with a modified exponential correlation. Institute of Radio Engineers, N. Y. , Proceedings, 43(10): 1381 -1383, Oct. 1955. 14 refs. , numerous eqs.

DLC--A phenomenological exponential space correlation of dielectric fluctuations is normally used to predict scatter field

strengths beyond the horizon. This paper introduces a modified exponential model which includes effects of the smallest

blob cutoff in the turbulent spectrum and rectifies the correlation's cusp at the origin. It is found that the present agreement of troposphere scatter experiments with the exponential

function does not depend on this cusp. It is suggested that

frequency-dependent tropospheric fields recently measured below 25 cm may indicate the influence of the correlation's fine

structure. The same model is then applied to the ionosphere,

where the extended range VHF scatter wavelengths just straddle the smallest blob size (r* 3 m) in the E layer. The turbulence fine structure is most important for this propagation and

gives a qualitative explanation of the curious dualism in frequency scaling laws observed at opposite ends of the VHF

band. Satisfactory variation of signal strength with scattering

angle is also predicted by this model. It is shown that scatter measurements can provide valuable estimates of the atmosphere's fine structure at various heights. --Author's abstract.

A-1335 Wheelon, Albert D. (Ramo-Wooldridge Corp, Calif. ), Diurnal

variations of signal level and scattering heights for VHF propagation. Journal of Geophysical Research, Wash. , D. C. , 62

(2h255-266, June 1957. 6 figs. , 16 refs. , 4+ eqs. DLC--The

scattering of VHF radio waves in the lower ionosphere is identified with turbulent fluctuations of the electron plasma. The

theory of gradient mixing is applied to the afternoon and early

evening periods, for which solar control is thought to dominate

meteoric contributions. The scattering cross -section for this

process UN

cr = 2tt r o \d h .

A-vr

L x

- 5

depends on ionospheric conditions only through the ambient

electron density-height profile's gradient dN/dh. It is found

that the afternoon decay of signal strength and simultaneous

increase of scattering height can be correlated with independent estimates of electron density and recombination coefficients
392

in the lower ionosphere. The observation of two scattering

levels on short paths and the lack of a midday maximum on

long paths is predictable. Diurnal variations of the frequency

dependence of these transmissions suggest a strong influence

of the earth's magnetic field. --Author's abstract.

A-1336 Wheelon, Albert D. (Ramo-Wooldridge Corp. , Los Angeles,

Calif. ), Radio frequency and scattering angle dependence of

ionospheric scatter propagation at VHF. Journal of Geophysical Research, Wash., D. C. , 62(1):93-112, March 1957. 8

figs. , 20 refs. , 4+ eqs. DLC--The weak and fluctuating radio

signals observed at distances of 1, 500 km on VHF are attributed to scattering from E region turbulence. It is noted that

propagation constants k = 47F /\ sin ( ^/2), corresponding to

the experimental frequencies (28 to 108 Mc), just straddle the

viscosity cutoff wave-number k, = (2 meters)"-'- of the region,

thereby giving a qualitative explanation for the curious dichotomy found in the experimental data. The two competitive turbulence theories are then developed in detail near the viscosity transition range. It is found that pressure fluctuations of

the ionosphere's neutral gases induce a spectrum of dielectric variations which reproduce the frequency and scattering

angle dependence of the experimental results quite well. A

theory of turbulent mixing of ionization gradients is then developed along the lines of Heisenberg's original treatment of

the velocity field. This process predicts a frequency variation

of power levels which is also satisfactory. It is concluded

that more precise, simultaneous measurements will be required

to choose between the two theories on this basis. --Author's

abstract.

A-1337 Wheelon, Albert D. , Refractive corrections to scatter propagation. Journal of Geophysical Research, Wash. , D. C. , 62

(3):343-349, Sept. 1957. 3 figs. , 12 refs. , 14 eqs. DLC--

The role played by the ionosphere's mean electron density for

scatter propagation is considered. An electron plasma at the

scattering point (1) increases the effective wave length and

(2) decreases the scattering angle. These effects combine to

modify the basic propagation variable

f'-

^"" AH'-^] Vi

by a factor which depends only on the instantaneous maximum

usable frequency for the path. Associated signal level variations are found to be insignificant for conventional VHF scatter

links. Such an analysis does provide an explanation for recent

observations of F layer scattered signals and their correlations

with f MUF/f. Apparent scattering-height changes caused by

variable refractive pulse delay times are also studied. --Author's abstract.
393

A-1338 Wheelon, A. D. (Space Technology Labs. , Inc. , Los Angeles,

Calif. ), Relation of turbulence theory to ionospheric scatter

propagation experiments (summary only). Journal of Geophysical Research, Wash., D. C, 64(12): 2230-2231, Dec. 1959.

ref. , eq. DLC--The subjects discussed are: 1) Statistical behavior of ionospheric scatter signals; 2) scattering of electromagnetic waves by turbulent irregularities; 3) spectrum of electron density deviations and its relation to turbulence; 4) signal

level and scattering heights, and finally, 5) an explanation is

given of some SID features in terms of increased attenuation.

--W. N.

A-1339 Whipple, Fred L. (Harvard College Obs. ), Evidence for

winds in the outer atmosphere. National Academy of Sciences,

Wash., D. C, Proceedings, 40(10): 966-972, Oct. 1954. 2

figs. , 27 refs. DWB--An integrated account of the numerous

methods of estimating winds above the "balloon level. " Some

of these are: meteor trains (visual and radio tracking and Doppler techniques), noctilucent clouds, night glow, aurora, sound

propagation, ionospheric motions, high altitude rockets, etc.

Hope is expressed that the IGY will increase our knowledge or understanding of these motions on a global scale. --M. R.

A-1340 White, Marvin L. (Central Radio Propagation Lab. , Nat. Bu.

of Stands. , Boulder, Colo.), Atmospheric tides and ionospheric electrodynamics. Journal of Geophysical Research,

Wash., D. C. , 65(1): 153-171, Jan. 1960. 11 figs. , 3 tables,

27 refs. , 35 eqs. DWB, DLC--A brief review is given of the

resonance theory of atmospheric tidal oscillations including

both thermal and gravitational excitation. Semiempirical wind

patterns for various latitudes are given in Fig. 1, and the semiempirical variation of solar semidiurnal wind velocities with

height are given in Fig. 2, based on (1) solar barometric var- iations at ground level (Chapman, 1951), (2) wind measurements at Balloon heights (Johnson, 1955), (3) radio meteor

echo experiments (Greenhow and Neufeld, 1955), (4) E-region

winds from radio pulse techniques (Briggs and Spencer, 1954),

and (5) airglow cell movements (Roach and others. 1958).

Finally, current work on the extension of modern tidal theory

(valid for a neutral envelope) into the dynamo region is discussed (White, in press). —Author's abstract.

A-1341 Whitehead, J. D. , The focusing of short radio waves reflected

from the ionosphere. Journal of Atmospheric and Terrestrial

Physics, 9(5/6): 269-275, Nov. 1956. 3 figs. , table, 5 refs.

,

6 eqs. DWB--Increases of amplitude for about 2 min of a 4. 2

Mc/s wave vertically reflected from F layer ("bursts") are shown by simultaneous observations at Cambridge (Eng. ) and

Swaffham, 15 km to E, to result from focusing by large scale
394

distortions moving horizontally overhead (Munro's travelling

disturbances). The average velocity was 98 m/s. There were

very few bursts at night, a rapid increase at sunrise, more in

the morning than afternoon, and a gradual tailing off at sunset.

--C E. P. B.

A-1342 Whitehead, J. D. , The absorption of radio waves in an ionospheric layer. Journal of Atmospheric and Terrestrial Physics,

9(5/6):276-281, Nov. 1956. 2 figs. , 2 refs. , 7 eqs. DWB--

Formulas are given for the absorption per unit length of waves

absorbed or reflected in the E or F region. The absorption of a 2 Mc/s wave reflected in a Chapman layer of critical frequency 3 Mc/s with and without taking account of the geomagnetic field shows that with the field a considerable amount of

the total absorption occurs near the top of the wave trajectory

in the deviating region. --C. E. P. B.

A-1343 Whitehead, J. D. , The absorption of short radio waves in the

ionosphere. Journal of Atmospheric and Terrestrial Physics,

10(1):12-19, Jan. 1957. 7 figs. , 4 refs. , 2 eqs. DWB-It is

shown that the reflection coefficients (p) measured for radio

waves on 2 and 4 Mc/sec reflected vertically from the ionosphere do not fit the expression -logp = A(f + f^'^ (1) appropriate to "nondeviative" absorption. Since the two frequencies

mentioned did not approach near to critical frequencies at the

time of the measurements, this failure cannot be ascribed to

excessive "deviative" absorption. If the measured values are inserted into the expression -log p = C + B(f + fr) (2) it is

found that (a) C varies with the sun's zenith angle but not with

solar epoch and is greatest in winter, (b) B is a very variable

quantity, it depends on the solar epoch. With values of B and

C deduced from measurements on 2 and 4 Mc/sec, equation

(2) gives a reasonable approximation to the measured values

of p on 2. 4, 3. 2 and 4. 8 Mc/sec. It is suggested that waves

in the frequency range 2 to 4. 8 Mc/sec are appreciably absorbed outside the nondeviating region, where equation (1) is appropriate. --Author's abstract.

A-1344 Whitehead, J. D. (Otago Univ. , Dunedin, N. Z. ), Distance

attenuation of radio waves reflected at vertical incidence from

the ionosphere. Journal of Atmospheric and Terrestrial Physics,

London, 12(2/3): 150-152, 1958. table, 3 refs. DLC--It is

shown that the assumption that the amplitude of radio waves,

propagated from a point source, falls off inversely as the group

path Pi leads to a value of apparent reflection coefficient of

the ionosphere which may be seriously in error, and in particular, to a large error in the measurement of the electronic collision frequency in the F region. --Author's abstract.
395

A-1345 Whitehead, J. D. (Univ. of Otago, Dunedin, New Zealand),

The absorption of short radio waves in the D, E and F regions

of the ionosphere. Journal of Atmospheric and Terrestrial

Physics, N. Y. , 16(3/4): 283-290, Nov. 1959. 6 figs. , 16

refs. DWB, DLC--The published values of the noon absorption of radio waves of frequencies 2, 2. 4, 4 and 4. 8 Mc/s

measured at Slough from 1947 to 1953 have been analyzed.

From the absorptions of 2 and 2.4 Mc/s waves, it has been

deduced that (a) the electronic collision frequency v, at the

height of the maximum electron density in the E region when

the sun's rays are incident vertically on the ionosphere is

(1.9 + 0. 1) X 104 per sec; and (b) the normal absorption in

the D region increases with increasing sunspot number,

whereas the additional absorption which occurs on certain

winter days and arises in the D region may decrease with

increasing sunspot number. The 4 and 4. 8 Mc/s waves were

reflected from the F region at noon. The absorption in the F

region is calculated from the known total absorption and the

calculated absorption in the D and E regions. The collision

frequency in the F region may then be found. At the height

of reflection of 4 Mc/s waves (150 to 180 km) it is (3. 6 + 0. 6)

X 103 per sec, and at the height of reflection of 4. 8 Mc/s

waves (180 to 200 km) it is (3. + 0. 6) X 103 per sec. The

significance of these results is discussed. --Author's abstract.

A-1346 Whitehead, J. D. (Otago Univ. , Dunedin, N. Z. ), Sudden

changes in the virtual height of radio waves reflected from the

E region of the ionosphere. Journal of Atmospheric and Terrestrial Physics, N. Y. , 12(1/2) .-99-102, Oct. 1959. fig., 5

refs. , eqs. DWB, DLC--It has been observed that the virtual

height of radio waves reflected from the E region shows discontinuous changes. The lower height reflections take place

from thin layers within the normal E region. From the measurements of the associated amplitude changes it has been possible to deduce that the electronic collision frequency at

110 + 5 km is (1. 3 + 0. 1) X 104 per sec and the semi-thickness of the thin layers is 4 + 2 km. --Author's abstract.

A-1347 Wiesner, Jerome B. (M. I. T. , Cambridge, Mass. ), A new

kind of radio propagation at very high freguencies observable

over long distances. Physical Review, 2nd Ser. , 86(2):141-

145, April 15, 1952. 5 figs., 8 eqs. DLC--Treats the discovery and some experimental results of the weak vhf ionospheric propagation type observable over ranges up to 2000 km

distance, but likely masked by other kinds of propagation at

distances less than 1000 km from the transmitter. Using 49. 8

Mc/s over a 1245 km path, the particular signal was observed

regardless of season, time of day and geomagnetic disturbances. Based on strong indications that the signal is returned
396

from the E region below the maximum ionization level, perhaps even below the absorption region (D region), a speculative explanation in terms of parameter is presented. --W. N.

A-1348 Wiesner, Jerome B. , New methods of radio transmission.

Scientific American, N. Y. , 196(1) :46-51, Jan. 1957. 8 figs,

(incl. photos). DWB, DLC--A non-technical, illustrated

article on the fundamentals of ionospheric and tropospheric

propagation, and especially on "scatter propagation" from the

troposphere and ionosphere. The latter enables fairly long

distance communication by means of 30 to 70 megacycle

waves, but equipment and operations are costly. Line-ofsight (30 mi) transmission is much cheaper but requires more

installation and personnel, and is not always possible in

Arctic or at sea. Some of the giant antenna used (e. g. at

Cedar Rapids, Iowa and S. Dartmouth, Mass. ) are illustrated. --M. R.

A-1349 Wiesner, Jerome B. , Communication using earth satellites.

Institute of Radio Engineers, Transactions, MIL -4(1): 51 -58,

Jan. 1960. 5 figs. , table, 3 refs. , 5 eqs. DLC--A review

of the use of earth satellites for reliable ionospheric independent communication circuits includes considerations of

losses in propagating path, directivity features, and influences such as Doppler shift. The effects of such influences

on bandwidth and range are illuminated. —Author's abstract.

A-1350 Wiewall, Miguel, Jr. , Further observations of ionospheric

drifts and related phenomena with spaced radio receivers.

Puerto Rico. Univ. College of Agricultural and Mechanic

Arts, Mayaguez, Contract AF 19(122) -476, (Study of Ionospheric Winds), Scientific Report, No. 4, and Final Report,

Jan. 1957. 167 p. 43 figs. , 80 tables, 14 refs. DWB

(M57 P977s)--A voluminous compilation of tabular and graphic

data on seasonal, diurnal and height variations in ionospheric

drift directions and speeds for vertical incidence pulse echoes

at 2. 33 and 4. 57 mc obtained at a Tripartite receiver network

at Mayaguez, Puerto Rico during Feb. 1954— summer 1956,

incl. Equipment is described and illustrated, computation

techniques outlined and turbulence conditions analyzed. The

method of "similar fades" has been replaced by the 6-point

correlation method of YERG (1955). -M. R.

A-1351 Wilkins, F. and Minnis, C. M. , Comparison of ionospheric

radio transmission forecasts with practical results. Institution

of Electrical Engineers, Proceedings, Pt. 3,98:209-220,1951

The production of muf forecasts for oblique transmission involves numerous operations on basic information obtained at

vertical incidence. At each stage, errors are introduced
397

whose cumulative effect determines the difference between

predicted and observed circuit performance. The sources of

the errors are examined and tentative values assigned to them

with special reference to F2 region. The computed value of

the total error is compared with results obtained on commercial and Service circuits, and with observations made by

other means. It is concluded that, although on the average,

agreement is good, discrepancies remain which need further

examination after the elimination of known sources of error. In a few cases, comparisons of predicted and actual times of

fades due to ionospheric absorption have been made. Although

the agreement between these times is reasonably good, it is

believed that predictions of the actual field strength may be in

error by large amounts.

A-1352 Williams, D. , The structure of high-frequency ionospheric

scatter signals . Institution of Electrical Engineers, Pt. B. , Vol. 105, Suppl. No. 8:19-26, 77, 1958. 7 figs. , 13 refs.

A-1353 Wilson, A. C. and Cottony, H. V. , High gain, low side-lobe

VHF antenna for ionospheric scatter communication. U. S.

National Bureau of Standards, NBS Report, No. 6022, Dec. 1,

1958. 7 p. 7 figs. (incl. photos), table, 8 refs. DWB--

A corner-reflector antenna having a width of ten wavelengths

and the length of reflecting surfaces of two wavelengths was

constructed, adjusted, and tested. The driven element was

a collinear array of ten half -wave dipoles. Dolph-Tchebyscheff current distribution designed for side lobe suppressions to -45 decibels was computed. The currents in the dipoles were adjusted as nearly as possible to this distribution.

The radiation patterns were measured and found to be quite

close to the computed. A half-power beamwidth of 9 degrees

and -40 db beamwidth of 28 degrees was obtained. The gain

was found to be approximately 21 decibels. It was further

found that the performance was stable with time and changing

weather conditions. --Authors' abstract.

A-1354 Wisbar, Herward, Wellenstreuunq und meteoride Einflusse

auf kurzen und den benachbarten ultrakurzen Wellen. (Wave

distribution and meteorite effects pn short and very short

waves. ) Archiv der Elektrischen Ubertragung, Stuttgart, 10

(8):343-352, Aug. 1956. 12 figs. , table, 16 refs. German

and English summaries p. 343. DLC--A long technical discussion of scatter-waves due to residual ionization, at medium

(500-2000 km) and very great (4000-11, 000 km) distances, probably due to meteor ionization. The influence of grazing frequencies and results of observations in 40-70 m/Hz range,

long enduring meteor echoes, atmospheric and tropospheric

influences at 40-70 m/Hz, effects of an ionospheric disturbance
398

or auroral storm, and commercial applications for radio, telegraph and telephone circuits, are discussed and illustrated

with schematic diagrams and synoptic charts. --M. R.

A-1355 Wong, Ming S. (AFCRC Propagation Lab. , Bedford, Mass. ),

Refraction anomalies in airborne propagation. Institute of

Radio Engineers, Proceedings, 46(9): 1628-1638, Sept. 1958.

16 figs. , foot-refs. , 5 eqs. DLC -Propagation at 250-10, 000

mc often encounters dense fadings, radio holes, antiholes or radio ducting. These anomalies are portrayed by ray tracings

using a differential analyzer which solves the simplified ray

equation

_A - n(h. x) +

_1_

dx2 h

Both hypothetical-prototype and complex-measured refractive

index profiles of the atmosphere are used for the analog computation of the ray tracings which are interpreted to explain

refraction anomalies in radio wave propagation, and are compared with signal strength measurements. They involve divergence of rays, and concentration and crossing of direct

rays in multipath transmission. Resulting radar angular and

range errors are shown, as are spatial variations of elevation

angles of arrival of interfering rays at the points where they

cross, corroborating radio-astronomical data on angular deviation of stars. --From author's abstract.

A-1356 Woodbridge, David D. (Redstone Arsenal, Alabama), Observed winds at high levels. American Meteorological Society,

Bulletin, 40(11): 549-553, Nov. 1959. 8 figs. DWB, DLC.

A-1357 Woodward, Richard Horace, Model of the ionosphere. Harvard Univ. Cruft Laboratory, Contract N5-ORI-7601 Technical

Report, No. 26, Jan. 25, 1948. 24 p. 14 figs., 23 refs. , eqs.

DWB--Observations and theories of a number of geophysical

phenomena associated with the ionosphere are summarized. A

proposed model of the ionosphere seems to provide qualitative

interpretations of most of these phenomena. In low and intermediate latitudes electrons are assumed to rise; they migrate

through the upper ionosphere to the polar region, where they

fall and complete the circuit through the ground. Under the

action of an electric field, positive ions, which are formed at

great heights by ultraviolet light, tend to rise, whereas negative ions descend. Since the ions are constrained to helical

paths along the sloping magnetic lines of force, positive ions

tend to collect in a ring near the plane of the geomagnetic

equator; negative ions accumulate in the polar regions. Solar

radiation pressure distorts the ion-ring and blows the tail to a height of several earth-radii. Electric discharges between the
399

positive ion-ring and the negative polar caps produce magnetic

disturbances and the associated auroral displays. --Author's

abstract.

A-1358 Wormell, T. W. , Winds at ionospheric levels — a survey of

recent British work. (In: American Meteorological Society

and Royal Meteorological Society, Proceedings of the Toronto

Meteorological Conference, Sept. 9-15, 1953. p. 33-34. pub.

1954. ) DWB--Various radio methods give velocities of 25-200

m/s, mostly near 80 m/s, higher in winter than summer and

higher in F (sometimes )> 200 m/s) than E layer. Diurnal and

seasonal variations are summarized. --C. E. P. B.

A-1359 Wright, J. W. ; Knecht, R. W. and Davies, K. (Comps. ), Ionospheric vertical soundings. International Geophysical

Year, 1957/1958, Annals, 3(IGY Instruction Manual): 1-167,

1957. 157 figs. (incl. forms), 21 refs. , tables. DWB--This

profusely illustrated volume contains a thorough and systematic treatment of vertical sounding theory and techniques prepared by members of the Boulder Laboratories in the U. S.

National Bureau of Standards. It presents the history of ionospheric research in polar years, the present IGY program

which involves observations at 150 stations; ionospheric physics (structure, wave propagation, effect of magnetic field,

absorption, scattering, variations of ionosphere, oblique incidence propagation, true height analysis); sounding equipment (pulse measurements, ionosondes and their adjustment,

use, antennas and photo-processing of records); interpretation

of ionograms: selection of trace, identification of layers, interpolation difficulties (spread echo, Es, middle and low latitude problems); reduction of ionograms: scaling, tabulation of

data and statistical methods; and data quality. Appendices

give schedules, suggestions for punch cards and research. -- M.R.

A-1360 Wright, J. W. and Knecht, R. W. , Atlas of ionograms, compiled for the URSI/AGI Special Committee on World-Wide Ionospheric Soundings. Boulder, Colo. , Central Radio Propagation Lab. , National Bureau of Standards, June 1957. 7 p. numerous charts. DWB (M10. 535 W951at)--A sizeable compilation of ionograms illustrate the diurnal, seasonal and geographical variations in types of records obtained by vertical sounding techniques all over the world. In Pt. I, ionograms are presented for summer and winter days, at 00, 06, 12 and 18 h

local time, for 2 geomagnetically quiet days. Material is ar- ranged by geomagnetic latitude without regard to hemisphere.

In Pt. II, ionograms illustrate specific phenomena: Es types,

disturbances (auroras, cosmic rays, SID's, lunar stratification

multiple echoes, solar flares, etc. ) and, finally, effects
400

associated with local times or season (such as sunrise, etc.

)

Observation and classification techniques are specified. -- M. R.

A-1361 Wright, J. W. and Norton, R. B. , Analysis of ionospheric

vertical soundings for electron density profile data, Pt. 1.

Facilities for convenient manual reduction of ionoqrams.

U. S. National Bureau of Standards, Technical Note, No. 14,

July 1959. 8 p. 4 figs. , 4 refs. DWB (M(055) U585te)--

Facilities for manual reduction of ionospheric vertical soundings to true heights are prepared using the "10 point" ratios of

Ventrice and Schmerling. A study of the effects of the earth's

magnetic field on true height calculations permits selection of

five sets of these ratios assuring equal accuracy of application for any part of the world. The facilities available are in

the form of transparent overlays and matching special graph

paper. --Authors' abstract.

A-1362 Wright, J. W. , Analysis of ionospheric vertical soundings

for electron density profile data, Pt. XL Extrapolation of observed electron density profiles above hmax F2. U. S. National Bureau of Standards, Technical Note, No. 19, June 1959.

8 p. 2 figs. , 8 eqs. DWB (M(055) U585te)--A tentative model of the F region above hmax is provided to permit extrapolation of electron density profiles into this region. The model

corresponds to a simple "Chapman" curve, and may be fitted

to true height data (obtained in Pt. 1) by a simple graphical

process. --Author's abstract.

A-1363 Wright, R. W. and Skinner, N. J. (both, Univ. College,

Ibadan, Nigeria), Equatorial spread-F. Journal of Atmospheric

and Terrestrial Physics, London, 15(1/2): 121 -125, Sept. 1959.

fig. , 2 tables, 5 refs. DLC--Spread-F conditions have been

examined for six low-latitude stations --Dakar, Khartoum, Djibouti, Ibadan, Nairobi and Leopoldville. It is shown that,

contrary to the general view, occurrence of disturbed magnetic

conditions inhibits the occurrence of spread-F layers during

the southern solstice at all these stations. The seasonal var- iation of the occurrence of spread-F is considerably changed

if, instead of all days, only magnetically quiet days are considered. In the northern winter there appears to be widespread

correlation of occurrence of spread-F across Africa. This is

shown to be due to the magnetic influence. --Authors' abstract.

A-1364 Wright, J. W. and Norton, R. B. , Facilities for convenient

manual reproduction of ionospheric vertical soundings to true

height profiles. U. S. National Bureau of Standards, NBS

Report 6031, Jan. 12, 1959. 6 p. 4 figs. , table. DWB

(621.584 U585fa).
401

A-1365 Wright, J. W. (Nat. Bu. of Standards, Boulder, Colo. ),

Note on quiet-day vertical cross sections of the ionosphere

along 75 W geographic meridian. Journal of Geophysical Research, Wash., D. C,, 64(10): 1631-1634, Oct. 1959. 3 figs.,

5 refs. DLC.

A-1366 Wright, J. W. (Nat. Bu. of Standards, Boulder, Colo. ), A model of the F-region above hTT> avF2. Journal of Geophysical

Research, Wash., D. C. , 65(1): 185-191, Jan. 1960. 6 figs. , table, 13 refs. , 4 eqs. DWB, DLC--A simple Chapman model

(scale height 100 km) of the ionosphere above the peak of the

F region is found to be in good agreement with the few observed profiles of this region. The ratio of the above-peak electron content implied by the model to below-peak electron content is found to vary from about 2. 8 to 4. 0, also in good agreement with observations. The model is used in conjunction

with electron density profiles observed from the ground to construct meridional cross sections along the 75 W geographic

meridian. --Author's abstract.

A-1367 Wright, J. W. and Fine, L. A. , Mean electron density variations of the guiet ionosphere, April 2. 1959. U. S. National

Bureau of Standards, Technical Note, No. 40-2, Feb. 1960.

50 p. numerous charts, tables, 5 refs. DWB (M(055) U585te).

A-1368 Yabroff, Irving W. , Reflection and transmission at a sharply

bounded ionosphere. Stanford University, Electronics Research Laboratories, Contract AF 18(603) -126, Progress Report No. 1, July 1957.

A-1369 Yabroff, Irving W. (Stanford Univ. , Stanford, Calif. ), Reflec - tion at a sharply-bounded ionosphere . Institute of Radio Engineers, N. Y. , Proceedings, 45(6): 750-753, June 1957. 6 figs.

,

7 refs. , eqs. DLC. Also issued as Stanford Univ. Electronic

Research Lab. , Contract AF 18(603)-126, Progress Report No.

1, July 1957. --A quantitative description of the waves transmitted into and reflected from a sharply-bounded, anisotropic

ionosphere with losses is given. Given curves show the effects of the earth's field and losses for a particular model of

the nighttime E layer at vlf. --Author's abstract.

A-1370 Yabsley, D. E. , Atmospheric radio noise levels in Australia. I. Measurements at 11. 5 Mc/s on two narrow-beam arrays and

on a short vertical aerial at 10 Mc/s at Rockbank, Victoria . Commonwealth of Australia, Commonwealth Scientific and In- dustrial Research Organization, Div. of Radiophysics, Technical Report No. 135, Oct. 1958.
402

A-1371 Yeh, K. C. and Villard, D. G. , A new type of fading observable on high-frequency radio transmissions propagated

over paths crossing the magnetic equator. Institute of Radio

Engineers, Proceedings, 46(12): 1968-1970, Dec. 1958. 5

figs. , 6 refs.

A-1372 Yerg, Donald (College of Agri. and Mechanic Arts, Univ. of

Puerto Rico, Mayaguez), Notes on correlation methods for

evaluating ionospheric winds from radio fading records. Journal of Geophysical Research, Wash., D. C. , 60(2): 173-185,

June 1955. 3 figs. , 2 tables, 9 refs. , 39 eqs. DWB--A cor- relation method requiring six values of the correlation coefficient is developed. Expressions for the drift velocity, fading

velocity, and characteristics velocity are obtained from a cor- relation theory extended to include an elliptical contour in the

horizontal plane. The physical significance of the derived

velocities is considered. Preliminary data indicate that the

correlation ellipse exhibits a preferred orientation and that

fading associated with random changes is as important as fading associated with a drifting pattern. --Author's abstract.

A-1373 Yerg, Donald G. , Observations of ionospheric drifts and re- lated phenomena with spaced radio receivers. Puerto Rico.

Univ. College of Agriculture and Mechanic Arts, Contract AF

19(122) -476, Scientific Report No. 3, Aug. 1955. 67 p. 29

figs. , 7 tables, 6 refs. , numerous eqs. --Radio Fading Records

have been obtained at spaced receivers since Jan. 1954. The

six-point Correlation Method has been applied to 86 records

corresponding to 2. 33 Mcs and to 68 records corresponding to

4. 57 Mcs. The Method of Similar Fades has been applied to

448 records for 2. 33 Mcs and to 271 for 4. 57 Mcs. Directions

and velocities are more variable in winter than summer, and in

summer are toward North at 4. 57 Mcs and toward northeast or southwest at 2. 33 Mcs. Large values of turbulence invalidate

velocities obtained by the Method of Similar Fades and make

unreliable directions computed from small samples. Elliptical

contours and anisotropic turbulence may result in small systematic differences between the two methods. A general expression for drift velocity is derived and related to correlation

analysis. Velocity vectors obtained for each component of

the Fourier expansion of the signal intensity-time records show

a grouping about a straight line for records characterized by

short mean fading periods and large turbulence and wide scatter for records with long fading periods and small turbulence.

-A. A.

A-1374 Yerg, Donald G. , Observations and analysis of ionospheric

drift. Journal of Atmospheric and Terrestrial Physics, London,

8(4/5) -.247-259, May 1956. 5 figs. , 5 tables, 4 refs. , 12 eqs.
403

DWB--Radio fading records at 3 spaced receivers at Mayaguez,

Puerto Rico, on 2. 33 and 4. 57 Mc/s are analyzed for drift.

In Feb. drift tends to be to SW, but with considerable scatter;

average speed 20 m/s at 2. 33 and 17 m/s at 4. 57 Mc/s. In

June drift was more definite; 17 m/s to NNE on 2. 33 and 12

m/s between WNW and NNE on 4. 57 Mc/s. A few observations in March (winter type) and April (summer type) are also

shown. Diurnal variation is discussed. Fading resulting

from random changes is always significant. The size and

shape of the correlation pattern are considered. The correlation method used is more reliable than the method of similar

fades, which gives excessive velocities. --C. E. P. B.

A-1375 Yerg, D. G. , An analysis of drifts of the signal pattern

associated with ionospheric reflections. Journal of Geophysical Research, 64(1):27-31, Jan. 1959. 5 figs. , 4 refs.

A-1376 Yonezawa, Toshiyuki (Japan, Central Radio Prop. Obs. ), On

some results of ionosphere study. International Council of

Scientific Unions. Mixed Commission on Ionosphere, Brussels, Sept. 1950, Proceedings, pub. 1951. p. 206-207. DWB

--Brief discussion of: 1) absorption of radio waves in ionosphere (about 20% in E layer and nearly 100% in F layer) due to

ions and relation to estimates of upper air density; 2) recombination coefficients obtained from analysis of F2 layer electron density variation during a solar eclipse (Feb. 5, 1943 in

Hokkaido); 3) a new method of obtaining values of recombination coefficients (doesn't work very well) and 4) values of

recombination coefficients obtained from night electron density variations of F2 layer, considering temperature change

( & - maximum 3. 3 in Dec. and minimum 0. 3(X1Q-I0cm3sec"l)

in June and July); a seasonal variation of 11:1. --M. R.

A-1377 Yonezawa, Toshiyuki, On the fluctuation in height of the F2

layer during the night. Japan. Science Council. Ionosphere

Research Committee, Report of Ionosphere Research in Japan,

5(4):203-204, 1951. DWB-Short discussion of observation re- sults, obtained during the 29th co-operative observation period

from March 10 to April 10, 1951. The height of F2 showed a marked variability (in many cases over 80 km in one hour).

The autocorrelation coefficient with the height after one hour

was 0.44, while this value for the electron density was 0. 73.

The correlation coefficient between simultaneous observations

at two stations with a distance of more than 1000 km was 0. 35.

-A. A.
404

A-1378 Yonezawa, Toshiyuki (Radio Res. Lab. , Tokyo), A consideration of the mechanism of electron removal in the F2 layer

of the ionosphere. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere in Japan, 7(1): 15-29,

1953. 14 refs. , 21 eqs. DWB--A mechanism of electron re- moval in the F2 region, which consists in the transformation

of atomic ions into molecular ones through charge transfer and

the subsequent recombination of the latter ions with electrons,

has been considered. It has been concluded that, although

this mechanism may be capable of interpreting the attachment

type of electron removal, it can hardly explain quantitatively

the value of attachment coefficient, and besides, there re- mains a discrepancy between theory and observation concerning the value of scale height associated with the decrease in

attachment coefficient with height. --Author's abstract.

A-1379 Yonezawa, T. , A consideration of the mechanism of electron

removal in the F2 layer of the ionosphere, Pt. 2. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 9(1): 17-37, March 1955. 2 figs. , 3 tables, 49 refs. , 54 eqs. DWB, DLC-Theoretical considerations on the mechanism of electron removal in the F2 region

have been made. The main observational facts hitherto obtained from the analysis of data can be summarized into three

items: (1) The temporal rate of electron disappearance is of the

attachment type. (2) The value of the attachment coefficient

is about lO-^sec"1 at the 300 km level. (3) The values of the

scale height associated with the decrease in the attachment

coefficient with height are roughly 100 km. The most probable

mechanism of electron removal, which consists of the charge

transfer reaction between atomic ions of oxygen and neutral

molecules of oxygen or excited nitrogen followed by the dissociative recombination between the resulting molecular ions

and electrons, is examined to see whether it can well interpret

these observational facts. It is concluded that there is at present no satisfactory theory of the electron removal in the F2

region which can yield a consistent picture of its mechanism.

A-1380 Yonezawa, Toshiyuki, On the influence of electron-ion diffusion on the electron density and height of the nocturnal F2

layer. Japan. Radio Research Laboratories, Tokyo, Journal,

2(8):125-136, April 1955. table, 17 refs. , 41 eqs. DWB--

Influence of electron-ion diffusion on the electron density and

height of the nocturnal F2 layer is considered. It is shown

that under some reasonable assumptions Chapman's distribution of electron density does not change its form through electron-ion diffusion, only the lowering of the level of maximum

electron density is brought about, the amount of which depends

on the molecular density, scale height, and temperature at the
405

height of the layer. It is also shown that any initial distribution of electron density tends to Chapman's one as time elapses, though there is a minor restriction on the initial distribution. As the actual F2 layer does not exhibit any systematic

tendency of lowering after sunset, we can obtain the lower

limit to the atmospheric molecular density in the F2 region,

which is found to be 5 X 10^ cm"3 and by about one order of

magnitude larger than the value obtained by extrapolating

rocket data. --Author's abstract.

A-1381 Yonezawa, Toshiyuki, New theory of the formation of the F2

layer. Japan. Radio Research Laboratories, Journal, 3(11):

1-16, Jan. 1956. 5 figs. , 21 refs. , 23 eqs. DWB--A new

theory is proposed to the effect that in the lower portion of

the F2 layer the height distribution of electron density is determined by electron removal due to its dissociative recombination with molecular ions of oxygen generated by the atomion interchange reaction between atomic ions and neutral molecules of oxygen, while in the upper portion it is determined by

electron-ion diffusion in the earth's gravitational field, the

maximum being produced at an intermediate height by both

processes. The theoretical variations of the maximum electron

density of its height with latitude conform with observations

fairly well except near the equator. The low-density (and lowtemperature) model of the atmosphere based on rocket data

seems to be preferable to the older model. The agreement with

observations will become more satisfactory if electron-ion diffusion in the horizontal direction as well as the electric fields

in the upper atmosphere and perhaps temperature effect are taken into consideration. --From author's abstract.

A-1382 Yonezawa, Toshiyuki (Radio Res. Labs. , Kokubunji, Tokyo),

A new theory of formation of the F2-layer. Journal of Atmospheric and Terrestrial Physics, London, 15(1/2) :89-94, Sept.

1959. 3 figs. , 6 refs. , 10 eqs. DLC--The importance is emphasized of the role played by electron-ion diffusion in the

mechanism of formation of the F2 layer. Taking into account

the electron-ion diffusion in the gravitational field as well as

the electron-ion movement in the vertical direction, the velocity of which is assumed to increase exponentially, with height,

height distributions of electron density for steady-state conditions have been calculated and are discussed. The latitudinal

distribution of the maximum electron density and the height of

its level have also been obtained and compared with observations, resulting in a reasonable agreement at least in their

broad features. --Author's abstract.
406

A-1383 Zanotalli, Guglielmo, Su alcune anomalie dell a freauenza

critica ionosferica durante un'eclisee di sole. (Anomalies of

the critical frequency of the ionosphere during solar eclipses.)

Annali di Geofisica, Rome, 6(3):367-372f July 1953. 2 figs.

,

3 refs. English summary p. 372. MH-BH--The results of the

ionospheric soundings carried out in Rome during the partial

eclipse of the sun of Feb. 25, 1952 are presented here. Three

minima were found in the electronic concentration; one before

the beginning of the eclipse, one for the maximum phase, and

one at the end of the eclipse. It is shown, admitting that the

cause of the two extreme minima is to be found in the external

zone of the visible part of the solar disk, that one can explain

the otherwise inexplicable retard of the last minimum with re- spect to the visible eclipse, and one can interpret, at the same

time, strong apparent variation in the coefficient of recombination of the ionospheric electrons. —Author's abstract.

A-1384 Zenneck, J. , Physik der hohen Atmosphare. (Physics of the

upper atmosphere. ) Ergebnisse der Kosmischen Physik, Leipzig, 3:1-37, 1938. 21 figs. , 28 refs. DLC-A scholarly and

highly technical summary of all current knowledge of the ionosphere and methods of investigation of the ionospheric layers.

In Pt. I, the physics of the ionosphere and physico-chemical

processes are discussed: in Pt. II, normal ionization and Pt.

Ill abnormal ionization are treated in detail and quantitative

relationships shown in graphs and tables. Variations in ionization with height and time (diurnal and seasonal), solar eruptions, winds and sudden changes are considered. In Pt. IV,

the origin of ionization (Dellinger effect) and knowledge of

pressure, temperature, atmospheric composition and horizontal and vertical air motion, electrical state in stratosphere

gained through radio-propagation studies and meteor phenomena

are also treated. The bibliography, though not extensive, is

useful. --M. RA-1385 Zhekulin, L. A. , Raspredelenie elektronnoi kontsentratsii s vysotoi po dannym opytov s raketami i iskusstvennymi sputnikami Zemli i ee vliianie na rasprostranenie radiovoln. (Distribution of electron density with height according to data from

rocket and artificial satellite experiments and its effect on

radio wave propagation. ) Iskusstvennye Sputnik Zemli, Moscow, No. 1:67-79, 1958. 5 figs. , 7 refs. , 27 eqs. DLC--

With the aid of relevant equations, the author presents a comprehensive examination of the propagation of radio waves at

high altitudes. The contents of this paper include the following, viz: distribution of the density of ionization with height;

effect of the distribution of ionization, as disclosed by the

most recent experiments, upon the propagation of radio waves;

extinction of radio waves and instable processes in the
407

reflection of an electromagnetic signal from a non-homogeneous - ly ionized layer. The solution of the problem of the propagation of electromagnetic waves in the ionosphere with the distribution of ionization is expressed in Airy functions. A sharp

variation of the ionization gradient occurs in the E layer of the

ionosphere since the continuous and approximately monotonic

increase of ionization with height is maintained. Hence, with

increase in the frequency, the level of reflection of electromagnetic waves is displaced gradually in higher regions of the ionosphere. The critical frequency W is that at which the dielectric penetrability for the ionization density N]., corresponding

to the level of the sharp ionization gradient becomes zero. The

effective height of the ionosphere increases sharply in the

transition through WQ and the extinction of waves increases

at the same time, since the intensity of the incoming signal

is slight. The curves of the establishment of signals reflected

from the E and F regions with distributions of ionization corres- pond to the most recent experimental data. --I. L. D.

A-1386 Zhurnal Tekhnicheskoi Fiziki. Moscow, v. 1, 1931- Latest

issue seen, 27(11), Nov. 1957. Issued by Akademiia Nauk

SSSR. Monthly (Irregular). Supersedes Zhurnal Prikladnoi

Fiziki and Fizika i Proizvodstvo. DLC--In each issue there is

an extensive bibliography. Section 10a — on radiophysics —

gives 15 or 20 references (each month) to literature on the ionosphere and ionospheric propagation from both native and foreign journals. --M. R.

A-1387 Zmuda, Alfred J. (Applied Physics Lab. , Johns Hopkins Univ.,

Silver Spring, Md. ), Some characteristics of the upper-air

magnetic field and ionospheric currents. Journal of Geophysical Research, Wash., D. C, 65(l):69-84, Jan. 1960. 3 figs.,

5 tables, 25refs., 9 eqs. DWB, DLC -Characteristics of the

upper-air magnetic field and ionospheric currents are determined through an analysis of published rocket data on the magnetic scalar intensity. For the region between the earth's surface

and the E layer of the ionosphere, the observed values are compared with values obtained by extrapolating the surface vector

field. The agreement between the two sets of values is very

good for equatorial flights but only fair for a flight at White

Sands, New Mexico. The equatorial, ionospheric current density, which has a maximum of about 21 amp/km^, varies considerably with time and location of the rocket flight. The equatorial electrojet has a current intensity of about 130 amp/km

and flows practically along the magnetic equator. Some of the

computed currents associated with the normal magnetic daily

variation are at variance with those expected from considerations, such as harmonic analysis, of the surface transient field

and sheet -current approximations. In the area around White
408

Sands (geomagnetic latitude 41 N) a large negative magnetic

anomaly exists that may contribute to the formation of the re- gion of low intensity of radiation that lies between the two

Van Allen radiation belts. —Author's abstract.
409

ANONYMOUS

A-1388 A new kind of propagation at very high frequencies. Franklin

Institute, Philadelphia, Journal, 254(5) :417-420, Nov. 1952.

DWB--A theory on tropospheric scattering by BOOKER and

GORDON initiated the experimental transmissions at 49 8 Mc/s

that started on Jan. 23, 1951 from Cedar Rapids, Iowa over the

774 mile path to National Bureau of Standard's receivers at

Sterling, Va. , for the purpose of establishing the diurnal and

seasonal characteristics as well as the behavior of the signal

during ionospheric disturbances. The experimental results

strongly indicate that the signal returns from the E region below level of maximum ionization, perhaps from below the absorbing region (D region). --W. N.

A-1389 Conference sur la Physigue de 1 'Ionosphere. International

Union of Geodesy and Geophysics, Bulletin d* Information,

3(5): 159, April 1954. DWB«Brief note on Conference on Ionosphere, Sept. 6-9, 1954 at Cavendish Laboratory, Cambridge,

to discuss a) lower ionosphere, b) irregular movements, c) F2

layer, d) mathematics of wave propagation in ionosphere. -- M.R.

A-1390 Electron density profiles in the ionosphere. Nature, London,

181(4626): 1770, June 28, 1958. DWB--The Radio Research

Station of the Department of Scientific and Industrial Research,

at Slough, has organized a program for computing electron density and the true height of the various layers of the ionosphere,

as a part of the United Kingdom's program of observations during the IGY. Data are obtained from four stations — Slough,

Ibadan, Singapore, and Port Stanley. --N. N.

A-1391 Ionospheric studies using earth satellites. American Geophysical Union, Transactions, 39(1): 169-174, Feb. 1958. fig.,

table. DWB, DLC--At the USNC-IGY meeting held on Nov. 5,

1957 at the Central Radio Propagation Laboratory (CRPL) of

the National Bureau of Standards, Boulder, Colorado, it was

decided that a refinement of experimental techniques be undertaken. Representatives from 24 laboratories and organizations

were present to give account of their observations of the Russian satellites. Ionospheric turbulence studied and the fluctuations and fading rates of ionospheric characteristics were

collectively discussed. Recommendations adopted are contained in this report. --N. N.
410

A-1392 Mobile ionospheric station. U. S. National Bureau of Standards, Technical News Bulletin, 35(4):45-47, April 1951. 3

figs. DWB--Besides a network of 60 ionospheric stations that

furnish data to the Bureau of Standards for forecasts of ionospheric or radio propagation conditions, a mobile ionospheric

research unit (with 2 tractors) can be moved to any critical

point in the propagation path to transmit impulses to the ionosphere, for reception at stations on either or both sides.

Results should give more knowledge of "fading. "--M. R.

A-1393 The physics of the ionosphere. Nature, London, 174(4436):

866-868, Nov. 6, 1954. DWB--Account of Physical Society

conference at Cambridge, England, Sept. 6-9, 1954. Contributions summarized include D. F. MARTYN on movements in

the F layer; D. K. BAILEY on forward scattering between 75

and 90 km; E. O. HULBERT on formation of ionized layers by

X-rays; S. A. BOWHILL on irregularities and movements in

ionosphere. There were several discussions of outstanding

ionospheric problems. It was emphasized that radio methods

measure movements of irregularities of electron density, which

are not necessarily the same as air movements and should be

termed "drifts" instead of "winds". --C. E. P. B.

A-1394 Radio communications mystery. Western Electronic News,

7(12): 38, Dec. 1959. --A second VLF signal arriving up to 10

sec after the first one is often heard, and may be explained

by the theory advanced by R. A. Helliwell. This brief article

deals with method and instrumentation (aboard the Explorer VI)

designed to check the ionospheric duct theory. --W. N.

A-1395 Radio field-strengths in the Tropics. Nature, London, 184

(4686): 605, Aug. 22, 1959. DLC--A brief note on the subject

with reference to a current report by W. R. Piggott on how to

identify the most effective type of ionospheric reflexion for

particular circumstances. --W. N.

A-1396 Radio research in the British Commonwealth. Nature, London,

171(4355): 683-684, April 18, 1953. --Account of Proceedings of a Specialist Conference on Radio Research in London Aug.

1948, published by H. M. Stationery Office (S. O. Code No.

47-148-1949). Includes references to ionosphere investigation in British Commonwealth.

A-1397 Researches on the geomagnetic distortion in the ionosphere. Japan. Science Council. Ionosphere Research Committee, Report of Ionosphere Research in Japan, 9(2):59-104, 1955. Contents: Maeda, Hiroshi, Observed facts of the geomagnetic dis - tortion in the ionosphere, p. 59-70. 6 figs. , 2 tables, 20 refs.

Maeda, Ken-ichi, Theoretical study on the geomagnetic dis-
411

tortion in the F2 layer, p. 71-85. 6 figs. , 5 tables, 18refs. , 22 eqs. Hirono, Motokazu and Maeda, Hiroshi# Characteristics of the F2 layer on the magnetic equator, p. 86-94. 4

figs. , 3 tables, 12 refs. , 12 eqs. Hirono, Motokazu, Effect

of gravity and ionization pressure gradient on the vertical

drift in the F2 region, p. 95-104. 3 figs. , table, 16 refs. , 32 eqs. DWB--In Pt. 1, an extensive study is made on the

latitude distribution and the daily variation of all ionospheric

layers (Fl, Fl and E) during the sunspot minimum period (1953-

1954), to examine the fact of geomagnetic distortion in the ionosphere, and the harmonic components of the geomagnetic Sq

variations are presented, analyzed from the data of the Second

Polar Year. In Pt. 2, the vertical and horizontal drifts of electrons in the F2 region are studied in connection with the geomagnetic variation and the effects of drifts on the F2 layer are

treated. It is found that the geomagnetic distortion in the F2

layer can largely be interpreted by the drift. In Pt. 3, the direct relation between the geomagnetic Sq variation and the vertical electron drift of the F2 region on the magnetic equator is

examined. It is shown that the electric field in the F2 region

accompanied by Sq electric current produces the vertical drift

which is sufficient to interpret the main features of the anomaly of the F2 region on the equator. It is to be noticed that

the main term of the drift velocity is diurnal. In Pt. 4, the

effect of gravity and ionization pressure gradient is examined

in relation to the vertical drift by electrodynamic force in the

F2 region. It is found that if the number density of the gas at

300 km level is not much less than lO^O/cc the semi-diurnal

variation of the hmF2 can be interpreted by drift theory.

A-1398 Station de Recherches Radio^lectrigues du D. S. I. R. . Slough,

England: distributions verticales de la densite electronigue

dans 1 'ionosphere pendant l'A. G. I . (Station for Wireless Researches of the D. S.I. R. , Slough, England. Vertical distributions of the electronic density in the ionosphere during the

IGY. ) International Scientific Radio Union, Brussels, Bulletin of d'information, n°109: 14-17, May/June 1958. 2 tables,

2 refs. DLC--The object of this note is to outline the computation program (electronic calculators) organized by the Station

for Wireless Researches of the Department of Scientific and

Industrial Research, at Slough, in order to determine the vertical distribution of the electronic density aloft in the ionosphere, the ionograms being the basis of this study. The realization of this work is a part of the program of the United Kingdom during the I. G. Y. --A. V.

A-1399 Third International Geophysical Year 1957-58. Journal of Scientific and Industrial Research, Sec. A, New Delhi, 14(4): 162-

163, April 1955. DWB--
412

Brief information on the enterprise is followed by an outline

of the co-ordinated work program set up by the National Committee of India. The names and addresses of the members are

listed. The national program is explained briefly under the

following subject headings: (1) World days, (2) Meteorology,

(3) Geomagnetism, (4) Airglow and aurora, (5) Ionosphere,

(6) Solar activity, (7) Cosmic rays, (8) Latitudes and longitudes, (9) Glaciology and (10) Oceanography. --W. N.

A-1400 To study whistlers . Science News Letter, Wash. , D. C.

,

67(1): 3, Jan. 7, 1956. DWB, DLC -Whistlers, which are radio waves of audiofrequency that are born of individual

lightning impulses, will receive special attention during the

International Geophysical Year, 1957-1958. Whistlers are not the same as cosmic noise due to radio waves from outer

space. The so-called "dawn chorus", a radio effect connected

with the aurora and magnetic disturbances and caused by the

bombardment of the earth by material shot from the sun, will

be also listened to. It is hoped that this will settle what

comes from the sun to disturb radio, TV and wire communications on the earth, particularly at the time of the greatest prevalence of sunspots. --A. MP.

A-1401 (Twenty-two field research projects scheduled by the Arctic

Institute of North America.

)

Science, Wash. , D. C. , 122

(3162) :235, Aug. 5, 1955. DLC, DWB--Projects centered at

Point Barrow, Alaska, and scattered through Alaska and North

Canada, in geophysics, radio propagation, auroras, geomagnetism and glaciology, among others, are mentioned and names

of principal investigators and institutions with which they are

affiliated are given. --M. R.

A-1402 The upper atmosphere. Nature, London, 174(4425) :334-336,

Aug. 21, 1954. DWB--Summary of a Symposium on the Upper

Atmosphere held by the Royal Meteorological Society at University of Edinburgh, July 15-17, 1954. SIR EDWARD APPLETON described present knowledge of complexity of upper atmosphere. Recent studies on the morphology of the ionosphere revealed departures from simple theory. Research on

recombination coefficient is described. IAN C. BROWNE

summarized data on air density and ionospheric wind shear

obtained from reflection of radio waves from meteor trails.

H. P. PALMER described work at Jodrell Bank on fluctuations,

attributed to drift of a screen above F2 region, of emissions

from Cassiopaea and Cygnus. D. H. JOHNSON described

solar tides at 100 mb level. D. H. MC INTOSH discussed

possibility of determining ionospheric winds from geomagnetic

observations. A. H. JARRETT explained use of multilayer

coatings in an interferometer for auroral spectrographs.
413

J. PATON discussed noctilucent clouds, including an observation of turbulence. --C. E. P. B.

A-1403 Vselennaia raskryvaet svoi tainy. issledovanie kosmicheskogo

prostranstva s pomoshch'iu raket i sputnikov. (The universe

reveals its secrets: investigations of cosmic space by means

of rockets and satellites. ) Pravda, Moscow, 48(196, i. e. 14, 955):3-4, July 15, 1959. photo, 8 figs. "Report issued

by A. N. Nesmeianov, Pres. of the Akad. Nauk. March 1959."

DLC (Slavic R. R. )--A substantial and official report of the

"informative" type giving details of progress in cosmis ray,

radio propagation, ionosphere, micrometeorite, magnetic, interplanetary gases, belt of high radiation, upper atmosphere,

composition, density, ionization (electron and positive ion

concentration), and biological research in space and, finally,

basic concepts for cosmic flights, as gained from the 3 Soviet

"Sputniks" and later space probe flights. A number of graphs

showing quantitative results in the above fields are included.

--M.R.

A-1404 Winds and turbulence in the upper atmosphere. Nature, London, 167(4251) :626-628, April 21, 1951. table. DLC--An ac- count of the Geophysical discussion at the Royal Astronomical Society on Feb. 23. Mainly describes radio methods but

P. A SHEPPARD discussed the meteorology, suggesting that

the high velocities reported (drifts up to 100 m/sec at heights

of 250-300 km) were probably due to quasi-geostrophic flow in

different directions at different levels. --C. E. P. B.

414

AUTHOR INDEX

Aarons, J. A-764

Abbot, Charles G. A-l

Abbott, W. N. A-2

Abe, S. A-875

Abel, W. G. A-3

Abel, William. A-4

Aden, Arthur L. A-5, 1291

Agranovich, V. M. A-6

Agy, Vaughn. A-7-10

Aida, Kazuo. A-913

Aikin, A. C. A-ll

Aitchison, G. J. A-12

Akasofu, Syun-ichi. A-13

Albrecht, Hans J. A-14-17

Alekseev, P. P. A-18

Allan, A. H. A-326

Allcock, G. McK. A-19-21

Al'pert, la. L. A-22-30

American Radio Relay League.

A-31

Anderson, A. D. A-32

Anderson, J. M. A-475

Anderson, J. R. A-891

Anderson, L. J. A-1318

Aono, Yuchiro. A-33, 788

Appleton, Sir Edward Victor

A-35-79 „ Archiv der Elektrischen Ubertragung. A-80

Ardillon, Jeanne-Marie. A-81

Argence, Emile. A-82-83, 85-

86, 1016, 1020

Arima, Y. A-1244

Arkhangel'skiT, B. F. A-87

Askar'ian^G. A. A-88

Ataev, O. M. A-89

Australia. Commonwealth Scientific and Industrial Research

Organization. A-90

Axman, E. A-91

Bai, C. Lakshmi. A-92

Bailey, D. K. A-93-96

Bailey, V. A. A-97-101

Bain, W. C. A-102-105, 238

Baird, K. A-106

Baker, W. G. A-107, 108

Bakhru, K. A-1076

Balser, M. A-109

Bandyopadhyay, P. A-110-111

Banerjea, B. K. A-1067

Banerjee, D. K. A-116, 118

Banerjee, S. S. A-112-119

Banerji, R. B. A-120-127

Baral, S. S. A-128

Barber, N. F. A-129

Barfield, R. H. A-1161

Barnett, M. A. F. A-35-36

Barney, J. M. A-1191

Barre, M. A-130-131

Barron, D. W. A-132

Barsis, A. P. A-899

Baruah, H. K. A-133

Baruah, Parukutty. A-133

Bateman, R. A-94, 134

Bates, David R. A-135-136

Bauer, Siegfried J. A-138-139,

338-340

Beagley, J. W. A-140

Bean, B. R. A-1037

Becker, Walter. A-141-152

Beckmann, B. A-153-155, 754

Belgian Congo and Ruanda

Service Meteorologique

A-156

Bellas, F. E. A-469

Bellchambers, W. H. A-157

Bender, Hertwig K. A-158

Ben'kova, Natal'ia Pavlovna

A-159

Benner, Arthur H. A-91,

160-163

Bennington, T. W. A-164-169

Berezin, U. V. A-381

Berg, Hellmut. A-170-172

Bergman, C. W. A-173

Berkner, L. V. A-94, 174-175
415

Berning, Warren W. A-176-

179

Best, Nolan R. A-180

Beynon, W. J. G. A-57, 61f 63,

70, 74, 181-192, 961

Bhagiratha, Rao E. A-985, 988,

991-991, 1167

Bhargava, B. N. A-193-196

Bhattacharyya, J. A-963

Bialecke, E. P. A-197

Bibl, Klaus. A-198-203, 1016

Bickel, John E. A-204-205

Bixby, L. H. , Jr. A-206-207

Bjelland, B. A-208

Blackband, W. T. A-209

Blair, James C. A-210

Blanchard, H. P. A-21 1-353

Blatt, E. L. A-212

Bolgianao, R. , Jr. A-213

Bolle, A. A-214-215

Bonnet, G. A-216

Boohariwalla, D. B. A-51

Booker, Henry George. A-217-

222

Bornholdt, John W. A-223

Borodina, S. V. A-25

Bossolasco, Mario. A-224-225

Boston University. Upper Atmosphere Research Laboratory

A-226

Bostwick, William E. A-828

Bouchard, Jean. A-227

Bourdeau, R. E. A-228

Bowe, P. W. A. A-229

Bowen, W. A., Jr. A-1140

Bowhill, S. A. A-230-233

Bowles, K. L. A-234

Bowman, G. G. A-787

Bracewell, R. N. A-102, 235-

240

Bramley, E. N. A-241-245

Bray, D. IV. A-1041

Bray, W. J. A-246

Breit, G. A-247-249

Bremmer, H. A-250

Brennan, D. G. A-251

Brice, N. M. A-252-253

Brice, P. J. A-254

Briggs, B. H. A-255-261

Brown, F. W. A-262

Brown, G. M. A-188-190,

192, 961

Brown, H. E. A-1207

Brown, J. N. A-1296, 1299

Brown, R. F. A-1192

Bruin, F. A-568

Brysk, H. A-264

Budden, K. G. A-265-272

Builder, G. A-42, 44, 47

Bureau, Robert. A-273

Burgess, B. A-209

Burkard, Otto. A-274-278

Burke, M. J. A-279

Busch, R. A-200

Cahill, Laurence J. , Jr. A-280-281

Calcutta. Univ. Institute of

Radio Physics and Electronics. A-282

Caldecott, R. A-283

Caller, R. M. A-284

Campbell, W. A-514

Carlevaro, M. A-333

Casselman, C. J. A-285

Caton, P. F. G. A-286

Chaffee, D. C. A-212

Chaffee, D. D. , Jr. A-287

Chandra, Sushil, A-288

Chao, S. H. A-289

Chapman, J. H. A-290-292

Chapman, Sydney. A-49, 293-

295

Chappell, D. W. G. A-296

Chatterjee, B. A-297-298

Chestnov, F. I. A-299-300

Chezlemas, Rene. A-757

Chivers, H. J. A. A-301

Chu, T. S. A-302

Chudesenko, E. F. A-30

Chvojkova, E. A-304-305

Clark, Clayton. A-306

Clark, G. L. A-475

Clark, J. F. A-228

Clemmow, P. C. A-270, 307-308

Cohen, D. S. A-309

Cole, A. W. A-310
416

Colin, L. A-1317

Collins, C. A-1031

Cologne. Universitat Meteorologisches Institut. A-311

Colwell, R. C. A-312

Commission Miste de l'lonosphere. Troisieme reunion

Canberra (du 24 au 26 aout

1952) A-313

Conda, Alyce M. A-I279

Cones, H. N. A-314

Coroniti, S. C. A-315, 933

Cottony, H. V. A-314, 316,

1353

Counter, V. A. A-317

Court, G. W. G. A-318-319

Cowen, Robert C. A-320

Cracknell, R. G. A-321

Crary, J. H. A-322, 549

Crichlow, William Q. A-323-

324

Crombie, D. D. A-129, 325,

326

Crompton, R. W. A-327

Croom, Sheila. A-328

Crow, D. A. A-329

Crow, Edwin L. A-330

Cummack, C. H. A-331-332

Currie, B. W. A-428

Cutolo, M. A-333-336

Dahl, O. A-1231

Dalgarno, A. A-337

Daniel, F. T. A-1035

Daniels, Fred B. A-139, 338-

340

Das, P. M. A-694

Datta, R. N. A-341

Datta, S. A-341

Davids, Norman. A-342-345

Davidson, David. A-346

Davies, Frank T. A-347

Davies, Kenneth. A-10, 185,

295, 348-349, 1359

Davis, R. M., Jr. A-350-351

Davoust, Claude. A-762

de Bettencourt, J. E. A-352

de Bettencourt, J. T. A-5, 1291

Dedrick, K. O. A-353

Delobeau, F. A-354

Delloue, Jean. A-355

de Maximy, Georges. A-356

Demers, Pierre. A-357

Denisov, N. G. A-358

De Voogt, A. H. A-359

Dickson, David, V. A-360

Dieckmann, Max. A-361

Dieminger, "Walter. A-142,

362-374

Dinger, Harold E. A-375-376

Disney, R. T. A-324

Dobiasch, R. A-391

Dokuchaev, V. P. A-377

Dolphin, L. A-753

Dolukhanov, M. P. A-378

Dominici, Piero. A-215, 379

Dougal, A. A. A-197

Dow, W. G. A-578-579

Dowden, R. L. A-380

Drachev, L. A. A-381

Driatskii, V. M. A-382

Drummond, J. E. A-383

du Castel, Francois. A-384

Dumont, Rene. A-385

Duncan, R. A. A-386

Dungey, J. W. A-387-389

Dyce, R. B. A-390, 567

Ebert, W. A-391

Edwards, L. C. A-3, 540

Egan, R. D. A-942

Egeland, Alv. A-918

Ehlers, H. A-391

Elder, J. S. A-1088

Elena, A. A-225

Elliot, G. L. A-392

Ellis, G. R. A. A-393-397

Ellyet, C. D. A-398-400

Engel, Leonard. A-401

Eshleman, V. R. A-402

Etzweiler, G. A. A-403

Evans, G. O. A-254, 654

Ewing, R. A. A-404-405

Fans el au, Gerhard. A-406

Farley, D. T. , Jr. A-407

Farmer, F. T. A-54
417

Fedorova, L. N. A-408

Feinberg, E. L. A-24

Feinstein, J. A-409-410

Fejer, J. A. A-411-415

Fennel, Perry. A-416

Ferraro, A. J. A-147, 417-418

Ferrell, O. P. A-419

Findlay, J. W. A-420-422

Fine, L. A. A-1367

Finney, J. W. A-350

Fitch, E. A-423

Fleming, John Adam. A-424

Florian, Endre. A-425

Forsgren, Sven K. H. A-426,

1061

Fosterling, Karl. A-427

Forsyth, P. A. A-428

Franklin Institute Laboratories

for Research and Development, Phila. A-429

Friedman, Bernard. A-430

Friedman, Herbert. A-431

Friend, A. W. A-313

Froese, Charlotte. A-1265

Fuchs, J. A-432

Fulton, B. A-433

Gallagher, P. B. A-435-436,

939

Gallet, Roger M. A-438-442

Gardner, F. F. A-443-446, 931

Garriott, O. K. A-447

Gates, D. M. A-448

Gautier, T. N. A-449

Gehrola, E. A-553

George, D. E. A-1319

Gerson, Nathaniel C. A-450-

461

Ghergi, M. A-333

Gherzi, Ernest. A-462-463

Ghosh, Mrinmayee. A-464

Ghosh, S. N. A-465

Ghosh, S. P. A-466

Gibbons, J. J. A-147, 288, 418,

467-472

Ginzburg, V. L. A-24, 473

Gipps, G. de V. A-786, 1189

Glass, C. B. , I. A-105

Gnanalingam, S. A-474

Golden, R. M. A-785

Goldstein, L. A-475

Golitsyn, G. S. A-476

Goodwin, G. L. A-191, 477-

478

Goody, R. M. A-479

Gopala, Rao U. V. A-196

Goroshankina, A. A. A-480

Goudet, G. A-481

Grace, Clinton H. A-482-484

Granalingam, S. A-485

Grant, J. P. A-486

Great Britain. Dept. of Scientific and Industrial Research. Radio Research

Board. A-487-488

Great Britain. Hydrographic

Office. A-489

Green, P. E. , Jr. A-981

Greenhow, J. S. A-490

Gregory, J. B. A-491-492

Grenet, Gaston. A-493

Griffiths, H. V. A-494-495

Gringauz, K. S. A-496

Groenewold, H. J. A-497

Grosskopf, J. A-498-500

Guha, U. C. A-1067

Gusev, V. D. A-501

Haas, Herbert W. A-502

Hachenberg, Otto. A-503

Hacke, James E. A-504

Hafstad, L. R. A-505

Hagen, John P. A-506

Hagfors, Tor. A-507-509

Hagg, E. L. A-348, 510

Hagihara, Y. A-512

Hajkova, Jaroslava. A-512

Halley, R. A-513

Hanson, G. H. A-514

Harang, Leiv. A-515-516

Harding, Iff. B. A-718

Hardwick, B. A-517

Harnischmacher, Ewald. A-518-

524

Harris, K. E. A-525

Hartman, L. M. A-526
418

Harts field, W. L. A-527

Harvard College Observatory,

Rocket Panel. A-528

Harvey, J. A. A-529

Harwood, J. A-240, 530-531,

585, 1123

Haselgrove, Jenifer. A-532,

1212

Haubert, A. A-533-534

Haviland, R. P. A-526, 535

Haycock, Obed C. A-536

Heading, J. A-307, 537-538

Heaviside, Sir Oliver. A-539

Hedlund, B. A. A-540

Heightman, D. W. A-541

Heisler, L. H. A-873

Heitler, Walter. A-542

Helliwell, R. A. A-284, 322,

442, 543-553

Henbrey, R. S. A-254

Henderson, C. L. A-296

Henissart, Martha. A-554

Hennessey, James J. A-555

Hentschel, E. R. A-842

Hepburn, F. A-556-558

Heritage, D. P. A-285

Heritage, J. L. A-204, 559

Hersperger, S. P. A-1192

Hess, H. A. A-560-561

Hewish, A. A-1063

Hibberd, F. H. A-97, 562-565

Higgs, A. J. A-97, 566

Hill, R. A. A-567

Hineken, F. W. A-568

Hines, C. O. A-569-574

Hitchcock, R. J. A-595

Hoehne, W. E. A-32

Hoffman, William C. A-575-576

Hofmeyer, W. L. A-577

Hok, Gunnar. A-578-580

Holt, Olav. A-208, 581

Hope, J. A-1154

Hopkins, H. G. A-246, 582

Hormuth, W. A-583

Horner, F. A-584-587

Hosking, R. H. A-588

Houston, Robert E. , Jr. A-589

Howe, G. W. O. A-590

Howe, H. H. A-1273

Howells, I. D. A-591

Hugenholtz, E. H. A-592

Hughes, C. J. A-865

Hultqvist, Bengt. A-593-594

Humby, A. M. A-595

Hunaerts, J. A-216

Huxley, L. G. H. A-327, 596-

598

Inaba, M. A-722

Ingram, L. J. A-50, 55

Inoue, Yuji. A-599

International Council of Scientific Unions. Joint Commission on Radio Meteorology. A-600

International Council of Scientific Unions. Mixed Commission on the Ionosphere,

2nd Meeting, Brussels.

A-601

International Council of Scientific Unions. Mixed Commission on the Ionosphere.

h. Y. Univ. A-602

International Geophysical Year,

1957/1958. Comite" Special.

A-603-604.

International Geophysical Year.

Indian Programme. A-605

International Geophysical Year,

1957/1958. U. S. National

Committee. A-606

International Scientific Radio

Union. A-607-610

Ionescu, T. V. A-611

Ishida, Tadashi. A-1245

Ishikawa, Masaru. A-859

Israel, H. A-612

Isted, G. A. A-324, 613-615,

724

Istomin, V. G. A-616

Iwai, Akira. A-617-619, 922

Jacchia, Luigi G. A-620

Jackson, Howard J. A-621

Jackson, John E. A-622-627,

1105, 1108-1109, 1112-1114
419

Jackson, Thomas T. A-223

Jackson, Willis. A-628

Jacobs, George. A-629

Jaeger, J. C. A-630

Jancel, Raymond. A-631-632

Janes, H. B. A-899

Japan. Science Council. Ionosphere Research Committee

A-633-634

Japan. Science Council, hat.

Committee for Geodesy and

Geophysics. A-635

Jastrow, Robert. A-636

Jean, A. Glenn, Jr. A-637

Jeffrey, Z. R. A-638

Jenkins, J. B. A-639

Jenkinson, I. S. A-279

Johler, J. R. A-640

Johnson, Charles Y. A-641

Johnson, Francis S. A-642

Johnson, M. A. A-308, 712

Johnson, R. A-643

Joint Technical Advisory Committee. A-644-645

Jones, I. L. A-209, 646-648

Jones, Robert E. A-649-653

Jouaust, Raymond. A-654-655

Jowett, J. K. S. A-656

Joy, W. R. R. A-710

Junakovic, F. A-657

Kahan, Theo. A-631-632

Kalinovskii, Aleksandr Boleslavovich. A-658

Kallmann, H. Korf. A-659-663

Kalra, S. N. A-664

Kamada, Tetsuo. A-665-666

Kamiyama, Hiroshi. A-667-673

Kan, Miyao. A-880

Kanaya, Sumio. A-857-859

Kane, J. A. A-624-626, 674

Kasemir, H. W. A-612

Kay, I. A-675

Kazantsev, A. N. A-676-677

Keitel, G. H. A-678-680

Keller, Herbert B. A-681-682

Kelley, Luther C. A-683, 936

Kelso, JohnM. A-482, 684-

690

Keneshea, T. J. A-947-948

Kennelly, A. E. A-691

Kerr, F. J. A-1117

Kessler, Edwin, III. A-692

Khakhalin, Viktor Stepanovish.

A-693

Khastgir, S. R. A-694-696,

1075-1076, 1196

Kilpatrick, E. L. A-697

Kimpara, Atsushi. A-698-702

Kimura, Yasuko. A-700

King, G. A. M. A-331,703

King, J. W. A-704-705

Kirby, Richard C. A-706-707

Kirchner, P. H. A-1041

Kitchen, F. A. A-146, 329,

708-713

Klemperer, H. A-352

Knecht, R. W. A-714, 1158,

1359-1360

Knight, Raymond M. A-775

Kobayashi, Tsuneto. A-715,

788, 1243

Koch, J. W. A-716-721

Kodaira, N. A-722

Koenig, H. A-723

Kojan, J. S. A-724

Kokurin, Iu. L. A-1263

Komesaroff, M. M. A- 725

Kompfner, R. A-956

Koster, J. R. A-726

Kotadia, K. M. A-727

Krasovskii, V. I. A-728-729

Kraus, Lester. A-730

Krause, George E. A-982

Krautkramer, Josef. A-731

Krishnamurthi, M. A-732

Kruse, F. W. , Jr. A-544-546

Kundu, M. R. A- 733

Laby, T. H. A-735-736

Ladd, A. W. A-778

Landecker, K. A-97

Landmark, Bjo'rn. A-581, 737-

742

Landsberg, Helmut E. A-320

Lange, L. Jerome. A-637, 1202
420

Lange-Hesse, Gunther. 743-744

Larenz, R. W. A-745

LaTourette, P. M. A-746

Laursen, Veggo. A-747

Lauter, Ernest August. A-748-

751# 1083

Lawrence, Robert S. A-752

Lawson, G. J. A-209

Leadabrand, R. L. A-753, 939

Leighton, H. A-399

Leinbach, H. A-772

Leithaser, G. A-754

Lejay, Pierre. A-756-758, 1034

Lepechinsky, Dimitri. A-513,

759-762

Liakhov, B. A-763

Lied, F. A-740

Lien, J. R. A-764

Lilley, C. M. A-640

Lindquist, Rune. A-767

Linford, Leon B. A-768

Little, A. S. A-769

Little, C. G. A-770-772, 961

Lorentz, Hendrick Antoon. A773

Losee, F. A. A-778

Lovell, A. C. B. A-774

Low, WardC. A-775-776

Lowell, Robert. A-180

Luscombe, G. W. A-777

Lutz, S. G. A-778

Lynch, W. M. A-353

Lyon, A. J. A-71, 76-77, 79,

779

Lyons, J. F. A-780

McCready, L. L. A-931

McCue, C. G. A-781

McKenzie, A. A. A-782

McKerrow, C. A. A-783

MacLeod, G. A. A-1199

Macmillan, R. S. A-784-785

McMorrow, D. R. A-764

McNeill, J. J. A-736

McNicol, K. W. E. A-786-787,

1189, 1204

Maeda, Ken-ichi. A-788-789

Maeda, Tsuyako. A-1070

Maenhout, A. A-791

Maehlum, Bernt. A-790

Maire, J. A-792-793

Major, G. A-295, 794

Malinovski, Al. A-796

Mallinckrodt, A. J. A-544-546,

797-798

Mambo, Masayoshi. A-1245

Manning, Laurence A. A-799-

804

Maple, E. A-1140

Marasigan, V. A-805-806

Marcou, R. J. A-764, 807

Mariani, F. A-808-812

Martyn, David Forbes. A-107,

813-816

Mason, Ruth F. A-817

Masotto, Antonio. A-224

Massey, N. S. W. A-818

Matsushita, Sadami. A-819,

1178

Maurain, Charles Honore.

A-820

Maxwell, A. A-821

Maxwell, E. L. A-1294-1295

Mayot, M. A-82, 85

Mazumdar, S. C. A-855

Mazur, Daniel G. A-180

Meadows, R. W. A-822

Meek, J. H. A-823

Mehrotra, R. R. A-112-115

Mende, H. A-824

Menzel, W. A-153-154, 825

Merrill, R. G. A-826-827

Merritt, Ernest. A-828

Mihran, T. G. A-829

Mikhnevich, V. V. A-830

Miller, J. W. A-482

Millington, G. A-329, 713,

832

Millman, George H. A-649-

650, 833-838

Mimno, Harry Rowe. A-839

Minnis, C. M. A-595, 840,

1351

Minozuma, F. A-841

Mirick, C. B. A-842

Misme, Pierre. A-384

Mitra, A. P. A-843-847, 996
421

Mitra, Sisir Kumar. A-848-852

Mitra, S. N. A-853-855

Miyaf Ken-ichi. A-856-859,

1243

Moeller, H. G. A-371, 373,

860

Mookf Conrad P. A-861

Moorat, A. J. G. A-779

Morgan, M. G. A-862-864

Morris, D. W. A-865

Motzo, M. A-866

Mouchez, P. A-513

Mrazek, Jiri. A-512

Miiller, Hans Gerhard. A-867

Mullaly, R. F. A-868, 869

Munro, G. H. A-870-873

Murphy, Anabeth. A-1267,

1270

Murth, Y. S. N. A-696

Murty, D. Satyanarayana.

A-986-989

Murty, T. V. S. A-874

Murty, Y. S. N. A-1145

Nagata, T. A-875, 910

Naismith, R. A-47, 52, 55-56,

876

Nakai, Taketosi. A-877-879

Nakajima, Jun. A-665-666

Nakata, Yoshiaki. A-880

Napoletano, Aldo. A-881

National Research Council.

United States National Committee on International Scientific Radio Union. A-882

Nawrocki, P. J. A-883, 1192

Nearhoof, H. J. A-688, 884

Nertney, R. J. A-467-468, 649-

650, 688, 885-887

Netherlands. Meteorologisch

Instituut. A-888

Neufeld, E. L. A-492

New York University, Institute

of Mathematical Sciences.

Div. of Electromagnetic Research. A-889

Newell, Homer E. , Jr. A-661,

890-891

Newman, M. M. A-392

Newman, Miss. M. A-326

Nicholas, B. A-220

Nicholls, F. G. A-735-736

Nickson, A. F. B. A-735-736

Nicolet, Marcel. A-216, 893-

894

Noonkester, V. R. A-895

North Atlantic Treaty Organization. Advisory Group for

Aeronautical Research and

Development. A-896

Northover, F. H. A-897

Norton, Kenneth A. A-898-900

Norton, R. B. A-1361, 1364

Obayashi, H. A-1244

Obayashi, Tatsuzo. A-901-906

Obolenskii, V. N. A-907

Obukhov, A. M. A-908

Ogata, Yoshiharu. A-909,

1244

Oguti, T. A-910

Ohio. State Univ. Dept. of

Electrical Engineering, Antenna Laboratory. A-911-

912

Okamoto, Hironobu. A-913

Oklahoma Agricultural and

Mechanical College. Research Foundation. A-914

Okumura, Y. A-916

Olesen, Jens Kirstein. A-915

Omberg, A. A-898

Omori, T. A-916

Oriol, Cardus J. A-917

Ortner, Johannes. A-594, 918

Ortusi, J. A-919

Osborne, B. W. A-920

Osborne, C. B. A-921

Ose, Masami. A-913

Outsu, Jinsuke. A-617-619,

922

Pabo, N. V. A-87

Pack, J. L. A-950

Packner, E. J. A-254

Paetzold, H. K. A-923-925

Panofsky, H. A. A-926
422

Parkinson, R. W. A-345, 927-

929

Parthasarathy, R. A-930

Paul, Adolf. A-201-202

Pawsey, J. L. A-444, 931

Pederson, P. O. A-932

Penndorf A-315, 933

Pennsylvania. State College.

Ionosphere Research Laboratory. A-934-935

Perlman, S. A-936

Perry, Loris B. A-1269

Peterson, Allen M. A-306, 753,

937-942, 1258-1260

Pfister, Wolfgang. A-943-949

Phelps, A. V. A-950

Phillips, G. J. A-255-256, 259,

951

Phillips, M. L. A-251

Physical Society of London.

A-952

Pickan, A. D. A-1105

Piddington, J. H. A-953-954

Pierce, E. T. A-286, 292, 556

Pierce, J. A. A-955

Pierce, J. R. A-956

Piggott, W. Roy. A-65-66, 68,

957-965

Pikel' ner, S. B. A-966

Pillet, Genevieve. A-757

Pineo, V. C. A-967

Pinus, N. Z. A-658

Pitteway, M. L. V. A-968

Plendl, Hans. A-969

Poeverlein, Hermann. A-970-

973

Poincelot, Paul. A-974-975

Polar Atmosphere Symposium.

A-976

Pope, Joseph H. A-549, 977

Power, Thomas S. A-978

Pratt, D. S. A-942

Prechner, L. J. A-166

Prenatt, Raymond E. A-979

Price, R. E. A-980-981

Pritchard, Mrs. A. G. A-76

Probst, S. E. A-982

Quinn, T. P. A-983

Rajan, V. D. A-113, 117,

1170

Ram, R. L. A-1142-1143

Ramana, K. V. V. A-990

Ramana Murthy, B. V. A-991

Rangarajan, S. A-984

Rao, B. Ramachandra. A-471,

985-992, 994-995, 997,

1167

Rao, B. V. T. A-993

Rao, M. K. A-993

Rao, M. N. A-996

Rao, M. Srirama. A-987, 994-

995, 997

Rao, T. Seshagiri. A-732

Rastogi, R. G. A-998-999,

1038

Ratcliffe, J. A. A-39, 54, 217,

596, 639, 1000-1014

Rawer, Karl. A-82, 130-131,

199-203, 519-524, 824,

1015-1027

Ray, S. A-1066

Rayton, W. M. A-771

Reber, Grote. A-1028

Reddy, C. A. A-1029

Rees, M. H. A-1030

Reid, G. C. A-930, 1031

Renau, J. A-1032

Revellio, Karl. A-1033

Revirieux, P. A-1034

Reynolds, L. G. A-582

Rice, P. L. A-S99, 1035

Richter, K. H. A-1036

Riggs, L. P. A-1037

Rivault, R. A-1039-1040

Robbins, Audrey R. A-328,

1011, 1042, 1212-1214

Roberts, C. R. A-1041

Robertson, W- J. A-283

Rogers, G. L. A-1043-1044

Romell, Dag. A-1045

Roof, R. G. A-771

Rose, G. A-371, 373
423

Ross, W. J. A-1047

Row, AnnL. A-1048

Roy, R. A-1049-1050

Rudloff, D. A-1051

Rukhadze, A. A. A-6

Rumi, G. C. A-1052

Rumsey, It. J. A-1053

Rusch, W. V. T. A-784-785

Russek, Joy. A-430

Russell, W. J. A-936

Rybner, J^rgen. A-915

Rydbeck, Olof E. H. A-1054-

1062

Ryle, M. A-1063

Sacco, L. A-1064

Sachdev, D. K. A-1065

Saha, A. K. A-1066

Saha, M. N. A-1067

Sales, G. S. A-1068

Samson, C. A. A-324

Sandoz, O. A. A-433, 1069

Sao, Kazuo. A-1070-1073

Sargent, C. J. A-449

Sastry, G. Sivarama. A-732

Sato, Teruo. A-1074

Sato, Teruyuki. A-669-670

Satyanarayana, R. A-1075-1076,

1253

Saxton, J. A. A-246, 1077-1079

Schenk, Karl. A-1080

Schilling, G. F. A-1081

Schindelhauer, F. A-1082-1083

Schlapp, D. M. A-1084

Schmelovsky, Karl-Heinz.

A-1085

Schmelzer, R. J. A-1086

Schmerling, E. R. A-288, 403,

1087

Scholte, J. G. J. A-1252

Schonland, B. F. J. A-1088

Schrag, R. L. A-470, 1089-1090

Schrott, R. A-1091

Schumann, Winfried Otto. A1092-1095

Schwentek, Heinrich. A-1096

Scott, James C. W. A-1097-

1099

Scott, J. R. A-1100

Scott, W. T. A-1199

Sechrist, C. F. , Jr. A-1101-

1103

Seddon, J. Carl. A-624,

1104-1115

Seljak, A. A-592

Serson, H. V. A-514

Sethuraman, R. A-1116

Shain, C. A. A-725, 1117

Shammatt, F. H. A-1118

Shapiro, B. S. A-30

Shapley, A. H. A-1119-1120

Sharma, S. K. A-1121

Shearman, E. D. R. A-1122-

1123

Sheppard, P. A. A-1124

Shibata, Hisashi. A-1245

Shiga, Tamenari. A-1071

Shimazaki, Tatsuo. A-1125-

1130

Shinn, D. H. A-217

Shirke, J. S. A-1131

Shmoys, J. A-1132-1133

Sicinski, H. S. A-580

Sigvard, A. A- 1225

Silberstein, Richard. A-527,

1134-1139

Silleni, S. A-214

Singer, Fred S. A-1140

Singer, S. F. A-1141

Singh, B. N. A-l 142-1143

Singh, R. N. A-1144-1146

Singh, Tel Pratap. A-1147

Singleton, D. G. A-1148

Sinno, Kenzi. A-1149-1150

Skeib, Gunter. A-1151-1152

Skinner, N. J. A-1153-1154,

1363

Slough, England. Radio Research Station. A-1155

Slusser, E. A. A-1156

Smith, Ernest Ketcham, Jr. A-351, 1157-1160,1211

Smith, R. A. A-97

Smith, R. L. A-549

Smith, W. B. A-109

Smith-Rose, R. L, A-1161-

1164
424

S&ensen, E. V. A-1165

Somayajulu, Y. V. A-1166

1167

Southworth, Mason P. A-1168

1169

Spa id, G. H. A-627

Spencer, M. A-260

Spencer, N. W. A-578, 580

Sprenger, K. A-749

Srivastava, CM. A-1170

Srivastava, J. P. A-1171

Srivastava, R. S. A-1197-1198

Stahmann, J. R. A-891

Staley, Raymond C. A-1172-

1173

Stanley, J. P. A-1174-1175,

1325

Stanford Univ. Radio Propagation Laboratory. A-1176

Staras, H. A-1177

Steiger, W. R. A-l 178

Stein, Sidney. A-1179, 1261-

1262

Sterne, T. E. A-1081

Stevens, E E. A-1069

Stoffregen, W. A-l 180-1 181

Storey, L. R. O. A-726, 1182-

1183

Straker, T. *W. A-102, 240,

1184

Strandberg, M. W. P. A-643

Stranz, Dietrich. A-1185-1188

Strohfeldt, M. A-1189

Stuart, R. D. A-1312

Stuart, Vf. D. A-936

Subbotin, B. T. A-2 11

Suchy, Kurt. A-200, 1024

Sugar, G. R. A-1190

Sullivan, A. W. A-1191-1192

Sulzer, Peter G. A-l 193

Surange, P. G. A-119

Sutton, D. J. A-327

Svenson, A. C. A-1207

Swenson, George W. , Jr. A-1194

Symposium on ionospheric

drifts. A-l 195

Tantry, B. A. P. A-l 196-1 198

Tanzman, H. D. A-1199

Taubenheim, Jens. A-1200

Taylor, William L. A-1201-

1202

Theissen, Emil. A-1203

Thomas, J. A. A-1204-1211

Thomas, J. O. A-187, 328,

1042, 1212-1215

Thomas, L. A-186, 1216

Thompson, M. C. , Jr. A-1217

The Threshold of Space: the

Proceedings of the Conference on Chemical Aeronomy

A-1218

Tibbals, M. L. A-285

Tiberio, C. A. A-214

Titheridge,' J. E. A-1219-1222

Toman, Kurt A-1223-1224

Tomner, J. A-1225

Tonning, Andreas. A-1226

Torres, J. S. A-555

Toshnival, C. R. A-1227

Towle, A A-592

Tremellen, K. W. A-709

Tsukada, Sohei. A-1228

Tufts College. Dept. of Electrical Engineering. A-1229

Tufts College. Dept. of

Physics. A-1230

Turnbull, Mrs. A. G. A-77

Tuve, M. A. A-247, 505,

1231

Uchikura, K. A-1244

Uglow, Kenneth M. A-180

Ulwick, J. C. A-764

Underhill, Bradford B. A-l 193

1232

Underhill, C. R. A-483

U. S. Army. Forces in the

Pacific. A-1233

U. S. National Bureau of Standards. Central Radio Propagation Laboratory. A-1234-

1238
425

Utah. University. Dept. of

Physics. A-1239-1241

Utlaut, W. F. A-1242

Uyeda, Hiroyuki. A-1243-1245

Yueda, Moroyuki. A-880

Valverde, J. F. A-1246

Van Allen, James A. A-280

Van Meter, D. A-1247

Van Valkenburg, H. M. A-1191

vanWyk, J. W. A-1088

Vassy, Etienne. A-824, 1249-

1251

Vawter, F. E. A-428

Veldekamp, J. A-1252

Venkateswarlu, P. A-1253

Verma, J. K. D. A-1049-1050

Vestine, E. H. A-1254

Vice, R. W. A-413-414

Vickers, M. D. A-1255-1256

Viienskii, I. M. A-1257

Villard, D. G. A-1371

Villard, Oswald G. , Jr. A-436,

939, 1258-1262

Vitkevich, V. V. A-1263

Volz, C. A-212

Voge, Jean. A-384

Wait, James R. A-637, 1264-

1283

Walters, L. C. A-640

Warren, E. S. A-109, 433, 1069

Warwick, James W. A-1284-

1288

Watanabe, Tomiya. A-1289-

1290

Waterman, A. T. , Jr. A-5,

1291-1292

Waters, D. M. A-1217

Watson, Kenneth M. A-730

Watson-Watt, Sir Robert A.

A-1293

Watt, A. D. A-1294-1295

Watts, J. M. A-314, 1296-

1305, 1319

Waynick, Arthur H. A-472,

1306-1310

Webster, H. C. A-787, 1311

Weekes, K. A-485, 1312-

1315

Weiffenbach, George C.

A-1316

Weisbrod, S. A-204, 1317-

1318

Weller, R. A-392

Wells, H. W. A-174, 301,

1319-1322

Wells, W. B. A-1323

Westcott, C. H. A-102

Westfold, K. C. A-1324

Whale, H. A. A-1325-1332

Wheeldon, A. J. A-1333

Wheelon, Albert D. A-1334-

1338

Whelan, E. H. A-1295

Whipple, E. C. A-228

Whipple, FredL. A-1339

Whipple, R. T. P. A-537

White, Marvin L. A-1340

White, W. B. A-661

Whitehead, J. D. A-1341-

1346

Wiesner, Jerome B. A-1347-

1349

Wiewall, Miguel, Jr. A-1350

Wilkins, F. A-1351

Williams, D. A-1352

Wilson, A. G. A-1353

Wisbar, Herward. A-1354

Wong, Ming S. A-1355

Woodbridge, David D. A-1356

Woodward, Richard Horace.

A- 1357

Wormell, T. W. A-1358

Woyk, E. A-305

Wright, J. W. A-1359-1362,

1364-1367

Wright, R. W. A-1153, 1363

Wii'ster, Hans -Otto. A-426

Yabroff, Irving W. A-1368-

1369

Yabsley, D. E. A-1370

Yates, G. G. A-267

Yeh, K. C. A-1261-126^ 1371
426

Yerg, Donald G. A-1372-

1375

Yonezawa, Toshiyuki. A-1376-

1382

Zacharisen, Donald H. A-330

Zanotelli, Guglielmo. A-1383

Zenneck, J. A-1384

Zhekulin, L. A. A-1385

Zhurnal Tekhnicheskoi Fiziki.

A-1386

Zirin, Harold. A-1285-1287

Zrauda, Alfred J. A-1387

Zschorner, H. A-924

ANONYMOUS. A-1388-1404

427

SUBJECT INDEX

Absolute temperature of the ionosphere A-432

Absorption (See Subject Outline, p. xiv)

Diurnal variation A-855,1096

Seasonal variation A-202,

364, 743, 960, 1285

Absorption measuring equipment

A-959

Absorption technique A-379,

403, 639, 1200

Acoustic wave effects A- 1226

Aircraft A-841

Air glow A-101, 431

Alfven waves (See:Magnetohydrodynamic waves)

Analysis methods

of ionospheric movement records A-1043

Antennas A-785, 826, 828,

858, 911, 1348

Dipole antennas A- 1101,

1102, 1353

Multiple-wire Delta antennas

A-314

Optimum antenna height

A-827, 900

Rhombic antennas A-1190

Rocket antennas A-621, 626,

1239, 1240

Telemetering notch antennas

A-502

VLF antennas A-784

Yagi antennas A- 1190

Anticyclonic circulation A-450

Arctic propagation A-4, 48,

227, 315, 382

Arctic troposphere A-87

Attenuation A-229, 325, 856,

1033, 1202, 1268, 1295,

1344

Auroral activities A-7, 87, 153,

157, 227, 301, 348, 368,

369, 390, 406, 516, 969,

1031, 1052, 1186, 1357

Auroral zone A- 1332

Autocorrelograms A-125, 219,

1190

Automatic measurement equipment A-163, 173, 263

Back scatter (See Subject Outline, p. xvii)

From ground A-306, 1179,

1258

From sea A-306, 575, 1172,

1258

Laboratory sea wave models

A- 1172

Bays A-668

Bifurcation A-lll, 298, 805,

811, 945, 1020, 1108,

1129, 1171, 1252,1256

Blackouts A-8, 762, 1242

Polar blackouts A-431, 766

Beacon techniques A-352

Bennet's ionic mass spectrograph

A-616

Breit and Tuve's method A-484

C-layer A-407, 1340

Chance coincidence/whistlers

A-322

Chromosphere A-599

Circular polarization A-58

Cloud formation A-357

Combined sweep and fixed frequency techniques A- 1320

Continuous wave method A-582,

627

Control-line method A-857

Control -point methods A-857

Corpuscular radiation A-157,

368, 939, 1186, 1319

Cosmic noise A-157, 316, 1031,

1285-1288, 1400

Absorption A-1287, 1288

Refraction A-1288
428

Cotton-mouton effect A-924

Counter techniques A-892

Coupling effects A-147

D-layer - (See Subject Outline,

page ix)

Dawn chorus A-284, 442, 549,

864, 977, 1300, 1400

Diurnal variation A-997

Dellinger fadeouts A-699

Delta phase height equipment

A-650

Diffraction A-217, 231, 242, 255,

256, 411, 1000, 1002,1044,

1279

Diffraction effects A-242

Direction finders A-229, 361, 587,

692, 695, 1198, 1204

Visual and recording type A-859

Directional drift method A-477

Direction finder techniques A-527

Dispersion effects A-343

Distant sea waves techniques

A-533

Doppler effect A-924, 1010, 1045,

1313, 1316, 1349

Doppler method A-29, 75, 533,

720

Dynamic probe technique A-578

E-Region - (See Subject Outline,

page ix)

El - A-141

E9

- A-141, 142, 1066

E (See Subject Outline,

page ix)

Diurnal variation A-260,

468, 477, 505

Season variation A-460,

483, 786

E analysis A-128, 165, 225,

s 372, 576

E annual distribution A-460

E

s Classification A-1208

E

s frequency A-128, 181, 351,

s 545

E intensity A-128

E movement A-450, 453-456,

s 458, 460, 477, 515, 528,

733, 790, 902, 1008, 1045,

1319

E Polar A-933, 1158

E spiral occurrence A-510

E

s World wide drift A-225, 1157,

s 1160

Earth's magnetic field A-336

Echo analysis A-365, 766, 780,

787, 1352

Amplitude A-251, 261

Components A-546

Dependency on illumination

A-95

Diurnal variation A-422, 774

Focusing effect A-494, 732,

937, 1020, 1021, 1023

Periodicity A-287

Phase A-249, 251, 420, 589,

752, 767, 778, 865

Seasonal variation A-422, 774

Echo reflectors (passive)

Balloons A-867

Meteors A-94, 399, 753,

774, 800, 801,1007

Moon A-29, 93, 139, 338,

567

Satellites A-155, 232, 620,

728, 729, 787

Sea waves A-533

Echo reflectors (positive)

Artificial electron clouds

A-436

Auroras A-753

Ion belts A-267, 1387

Coupling echoes A-767, 929

D-echoes A-223, 397, 414,794

Delayed echoes A-755, 937,

938, 951

E-echoes A-198, 253, 258, 261,

420, 422, 589, 696, 727,

739, 761, 766, 1090, 1116,

1244

F-echoes A-198, 245, 253, 261,

420, 821, 938, 1116, 1244,

1311

Left-handed M echoes A-696
429

Long delayed echoes A-248,

267, 470, 777, 932

Multi-hop delayed echoes A-329,

778, 780, 833, 834, 856,

1020, 1090, 1097, 1311

Night echoes A-253, 787

Peculiar echoes A-913, 939,

1097

Short delayed echoes A-42

Short-lived echoes A-1117,

1190

Split echoes A-lll, 194, 220,

243, 298, 394, 396, 497,

560, 787, 885, 945

Weak echoes A-474, 485

Z-echoes A-393, 394, 396,

1311

Echo detectors

Weak echo detector A-474

Echo methods A-203, 1231

Tuve and Hafstad's method

A-249

Eclipses A-49, 216, 237, 608,

1033, 1383

EHF (>> 30, 000 mc, < 10mm ) A-496, 500

Electrohydrodynamic drag A-730

Electron collisional frequency

A-48

Electron density of interplanetary

space A-431

N(h) Electron density A-120, 146,

149, 150-152, 187, 339

Lunar echo method A-139

Booker-Seaton's method A-146,

152, 802

Electronic computers A-1398

Electrostatic fields A-407

Energy trajectories A-86

Equinoxes A-81, 157

Exosphere A-1040

Experimental transmissions - (See

Subject Outline, page xxiii)

Extraterrestrial influences A-2,

201, 220, 836

Extraterrestrial radio waves A-725,

732, 770, 954

F layer propagation lower frequency limit A-433

F-Region - (See Subject Outline

page x)

Diurnal variation A-157, 1126,

1127, 1377

Seasonal variation A-1363

Thermal equilibrium A-135

Disturbances (See Subject

Outline, page x)

F, - A-43, 52, 67, 78, 503,

1 1066

F

2

- (See Subject Outline

""" page x)

Vertical movement A-1011

Horizontal movement A-170,

182, 186, 235, 260, 279,

529, 647, 813, 1014,

1216, 1223, 1246

Critical frequency (See

Subject Outline p. xi)

Fading - (See Subject Outline

p. xix)

Diurnal variation A-193, 194,

1003

Periodic variation A-694, 1142r 1144, 1196

Seasonal variation A-194

Applications A-519, 522, 524,

533, 691, 1147

"Fast" fading A-191, 230, 421,

694, 841, 902, 929, 1116

Magneto-ionic A-997, 1029

Pattern classification A-114,

115, 122, 126, 154, 191,

301, 1144, 1196, 1228

Random fading A-1196

Rate A-210, 233, 718, 899,

1159

Record analysis A-1053, 1187

Satellite signals A-233, 565,

620, 677, 710, 711, 924,

1165, 1199, 1210

"Slow" A-191, 230, 694, 929,

994, 1093

Velocity distribution A-121,

124, 230, 252, 995
430

Faraday effect A-339, 340, 565,

567, 979, 1010, 1165

FM radio relays A-900

FM teletype systems A-900,

1192

Fog A-1156

Frequency allocations A-655,645

Measurements A-664

Frequency choice A-95, 96, 201,

202, 350, 466, 971,1069,

1204, 1232

Frequency steppers A-592

Fronts A-137, 157

Geomagnetism - (See Subject

Outline, p. xviii)

Graphical methods

Ray-tracing A-868

Transmission loss vs. distance and antenna heights

A-1035

Wave paths A-971

Ground waves A-36, 204, 797,

798

Group height techniques A-ll,

471

Group retardation recorders A-42

Group velocity A-869, 1280

Gyrocompasses A-921

Gyro waves A-101, 333, 1098,

1145

Gyro frequency A-92, 99, 335,

478, 564

Diurnal variation A-341

Gyro- interaction A-334, 335,

478, 562, 564, 866, 1257

Height measuring equipment

Vertical incidence A-484,1364

Height of irregularities giving

rise to fading A-123

HF (3-30 Mc, 100-lOm )-(See

Subject Outline, p. iv)

Hiss A-284, 442, 1300

Hurricanes A-138

Impulse absorption methods A-232

Impulse echo methods A-172, 311,

545, 546

Impulse equipment A-969

Influence of instruments on data

A-15, 17, 528, 722

Instrumental correction methods

A-779

Interaction A-333, 412, 414,

563, 564, 596-598, 705,

856, 1257

Interferometers

Ryle's phase-switching interferometer A- 1284

EHF dispersion interferometers

A-496

Dispersion interferometers

A-728

Ionization A-55

Ionospheric investigation methods

A-43

Ionospheric research instruments

A-553

Ionospheric structure A-299, 300,

924, 925, 1365

Fine structure A-223, 546,

710, 949, 1217, 1327, 1334

Diurnal variation A-157, 871,

1126, 1127, 1280, 1377

Seasonal variation A-871,

1363

Latitudinal variation A-595,

597, 961, 998

Longitudinal variation A-273-

275, 431, 443, 445, 446,

699, 702, 782, 906, 1191.

Ionospheric thunderstorm equipment

A- 1180

Ionization belts A-267, 932, 1387

Ionized cloud patches A-128, 261,

297, 306, 576, 613, 1077,

1148, 1176, 1186, 1206,

1319

Ionized cloud patches, blanketting type A-297

Ionized cloud patches, thin layer

A-297

Ionized hydrogen A-922

Ionizing layers A-38, 40, 114, 153,

247, 252, 261, 303-305, 384,

676, 691, 1049

I. P. S. (Australia) method A-857
431

Kerr modulator A-1056

Knife edge A-1194

Langmuir's probe technique

A-579, 580

Laboratory equipment for simulated ionosphere A-1230

LF(<300kc, 10-i km ) All,

25, 91, 122, 123-125,

(See Subject Outline,

p. xv)

Layer formation A-71, 237, 238,

400, 599, 671, 676, 691,

734, 839, 843, 1006,1021,

1381, 1382

Layer tilts A-244, 1046, 1050,

1179, 1261, 1328, 1330

Lightning A-897, 1039, 1052,

1088, 1118, 1170, 1198,

1323

Long range propagation A-16,

19, 20, 24, 102, 105, 140,

185, 204, 206, 210 (See

Subject Outline p. xvi)

Lateral deviation A-858, 859

LUHF A-14, 168, 514, 857, 858,

982

Machine computation methods

A-350, 418, 532

Of scattering A-678

Magnetic compasses A-921

"Magnetic" sound waves A-954

Magnetic storms A-69, 78, 89,

91, 196, 227, 281, 301,

517,591, 595, 737, 743,

969, 1253, 1300, 1319

Magneto-hydrodynamic waves

A-13, 387, 388, 966, 1290

Magneto-ionic duct propagation

A-553

Magnetometer flights A-280

Meteorological elements A-163,

541, 644, 698, 754, 827,

861, 881, 898, 1404

Meteor forward scatter A-423,

581, 1077, 1078

Meteors A-59, 101, 128, 210,

399, 423, 647, 800, 1052,

1117, 1354

Mesopause A-11 10

MF ( <3 Mc, 1000-100 m ) A-9, 11, 12, 36, 47, 97,

141, 142, 145, 149 (See

Subject Outline p. xv)

Missile tracking systems

DOVAP A-176, 177

Mitra's method A-515

Mobile ionospheric research

stations

Tractor A-1392

Modulation A-1292

Modulation techniques A-717

Mogel-Bellinger effects A-1083

MUF A-4, 10, 20, 57, 61, 70,

92, 115, 145, 160 (See

Subject Outline p. xxii)

Diurnal variation A-1015

Seasonal variation A-181

MUF calculation A-1214

MUF, German method A-1015

Multivibrators A-505

Navigation aids A-1248, 1251

Networks and storm warning

systems A-166, 489, 584,

656, 657, 724, 876, 1119,

1164, 1234

Nocturnal propagation A-391

Noise A-284, 301, 554, 583,

840, 931, 1151, 1271,

1302

Temperature A-936

Noise level

Diurnal variation A-751,

1191

Seasonal variation A-1191

Annual variation A-751

National and local noise

level predictions A-323,

324, 347, 451, 1191, 1370

Networks A-324, 1202

World wide noise level predictions A-323

Noise equipment A-451
432

Nomogram and slide rule

method A-360

Non-deviate absorption A-ll

Nuclear explosions A-702, 941f 1178, 1242

Numerical solutions of differential eqs. A-269, 413

Oblique incidence technique

A-223

Optimum MUF A-160

Oscillators A-955

Oscillatory movement of ionosphere A-1147

Outer atmosphere (space) A-21,

29, 209, 267, 387, 636,

932

Panoramic ionospheric echo

recorders A-765, 1181,

1319, 1320

Pedersen rays A-955

Phase difference A-326, 752,

767, 854, 981, 1184,

1198, 1204, 1217, 1263

Phase velocity A-1280

Phase height instruments A-589

Phase height techniques A-ll,

650

Phase measuring techniques

A-173, 236, 752

Phase-shift keying systems

A-721

Plasma A-197, 475, 568, 579,

679, 730, 745, 922, 950,

954, 1024, 1335, 1337

Polarization A-5, 39, 41, 44,

54, 58, 88, 100, 105,

147, 211, 239 (See Subject Outline p. xv)

Prediction techniques A-823

Pressure A-75, 829, 830, 881

Pseudo whistling device A-619

Pulse repeaters A-404

Pulse sounding techniques

A-582

Pulse technique A-1298

Putter technique

Extended A-126, 172

Radars A-24, 404, 405, 481,

525, 566, 577, 753, 796,

898, 940, 1036, 1048,

1052, 1099, 1117, 1261

Radar target tracking methods

A-32

Radiation A-397

Unusual A-301

Radio amateur observations

A-1034

Radio astronomy A-566, 574,

608, 1013, 1162, 1284-

1288, 1321, 1355

Radio communication

At sea A-434, 913, 921, 1051,

1348

By the Pedersen beam A-1022

In air flights A-842

In space A-567, 620, 663,

711, 936, 1165, 1292,

1311, 1349

Maintenance A-154

Transoceanic A-956

Radio communication disturbances

Storms, etc. A-158, 168, 329,

449, 584, 629, 656, 708,

792, 921, 947, 1051, 1150,

1391

Nuclear explosions A-762, 819,

941

Radio communication forecasting

A-14, 61, 73, 96, 214, 351,

425, 513, 514, 518, (See

Subject Outline, p. xxii)

Radio communication, forecasting

accuracy A-1150, 1351

Radio communication forecasting

methods A-518

Radio methods A-1358, 1404

Winds A-801, 1358

Radio "rise" and "set" method

A-29, 30

Radio-visual forecasting

method A-828
433

Radiogoniographs A-791

Lugeom-Mobile type A-791

Radiometers A-316

Radio navigation A-1251

Radio star scintillation A-770,

815, 816, 821, 836,

1007, 1148, 1321

Radio telescopes A-725

Rain A-1156

Receivers

Signal Corps BC 969

A-1191

Signal Corps Be 779

A-1191

Even-Knight radio astronomy

receiver,model 1620

A-1286

Reception A-1219

Antipodal A-305, 620, 859,

923, 1165, 1329

Reciprocity A-109

Recording method of disturbances

over certain distances

A-792

Reduction methods

Of Doppler shift errors A-720

hf records to Nh profiles

A-1087, 1220, 1221, 1361,

1362

Reflection A-19, 35, 38, 92,

97, 98, 102, 103, 112,

(See Subject Outline,

p. xiii)

Multiple A-112, 134, 183,

286

Obligue incidence A-103,

105, 129, 165, 181, 183,

205, 211 (See Subject

Outline, p. xiv)

Steep incidence A-240

Vertical incidence A-113,

116, 153, 161, 163, 165,

219, 230 (See Subject

Outline, p. xiv)

Z-incidences A-394, 1076

Refraction A-43, 54, 93, 100,

247, 303, 304, 590 (See

Subject Outline, p. xiv)

Relative humidity A-836

RF-probe technique A-625, 626

Riometers A-772

Rockets (See Subject Outline,

p. xxv)

Rocket borne equipment A-622,

641, 982, 1239, 1394

Rocket cameras A-1239

Rocket transmitters A-776,

1240

Rocket transmissions A-621-623,

627, 663, 728, 983, 1104-

1110, 1112, 1114, 1115,

1140, 1141, 1385, 1387

Satellites (See Subject Outline,

o. xxv)

Alpha I. A-613, 1081

Alpha II. A-1081

Beta A-620

Explorer VI. A-1394

Sputnik I. A-924, 1010, 1165

Sputnik II. A-924

Sputnik III. A-305, 930

Satellite Doppler measurements

A-1199, 1210, 1217

Satellite Doppler navigation system A-1316

Satellite equipment A-526

Satellite motions A-1292

Satellite orbit characteristics

A-506, 1010, 1245, 1292

Satellite orbit predictions A-179,

711, 947

Satellite radio receivers A-1047

Satellite radio transmitters

A-1047

Satellite signal propagation

A-305, 613, 620

Satellite tracking A-506, 526, 620,

914, 923, 942

Satellite transmissions (See Subject Outline, p. xxiii)

SC A-875

Scattering A-27, 113, 116, 117,

131, 143, 231, 234 (See

Subject Outline, p. xiv)
434

Scatter communication systems

A-423

Scatter propagation A-91, 104,

147, 234, 254, 264 (See

Subject Outline, p. xvi)

Scatter sounding A-1258, 1259,

1261

S. E. A. Sudden enhancement of

atmospherics A-1065

Selective whistler detector

A-355

Self-demodulation A-101, 336,

705, 719, 778

Sferics A-2, 25, 87, 103, 229,

265, 266, 286, 443 (See

Subject Outline, p. xxi)

Sferics observation techniques

A-291, 665

Photography technique

A-286

Synchronic recording

A-1151

Sferics classification A-286, 291,

558, 698, 700, 735, 883,

1088, 1198

Accuracy of spotting A-1152

Diurnal variation A-158, 700,

1065, 1082

Frequency A-291, 292, 554,

656, 698, 722

Periodicity A-554

Distribution A-878

Intensity A-665, 699, 700,

1065

Slow tails A-557

Sferic recorders A-1197

SHF (3, 000-30, 000 Mc, 10-lcm ) A-51, 583, 919, 1077,

1156, 1355

Ship observations A-1051

Signal intensity A-706

Similar fades method A-1350,

1373-1374

Six-point correlation method

A-1350, 1373, 1374

Sky waves A-13, 173, 204, 548,

965, 1017, 1184, 1267,

1295, 1312

Sky wave field intensity A-788

Sky wave problems A-548

Solar activities A-43, 52, 78,

87, 142, 193, 301 (See

Subject Outline, p. xvii)

Solar corona A-473, 836

Solar flares A-103, 198, 593,

699, 751, 904

Solar radiation A-9, 237

Diurnal variation A-110

Sun emitted waves A-93, 954

Sunspots A-14, 56, 62, 64,

66, 135, 166, 167 (See

Subject Outline, p. xvii)

Sunspot cycles A-252, 273,

793, 1015

Sounding equipment A- 109, 133,

480, 762, 874, 1049

Backscatter sounders A-1123,

1176

Echo-sounding apparatus

A-1091

IGY 3-frequency back-scatter

sounder A-942

Ionosondes A-933

c-2 A-1242

Mallard radar sonde system

A-525

Raw in sets A-722

Sounding recorders

Model C-4 A-1301

Sounding methods A-1359

Space exploration A-636, 663,

729, 922-924, 940, 947,

978, 1013, 1047, 1081,

1387, 1403

Spaced receiver method A-290,

296, 301, 318, 354, 529,

530, 646, 649, 679 (See

Subject Outline, p. xxvi)

Spectroscopes A-904

Spectrometer A-641

TV - spectroscope A-226

Splitting A-133, 885, 945, 1171,

1299

Spontaneous path predictions

A-1260
435

Spread F (Triple split) A-lll,

194, 220, 243, 394 (See

Subject Outline, p. xi)

Stratosphere A-228, 479, 667

Survey of methods

Of measurements A-465

For upper atmosphere information A-1249

For Sferics measurements

A-864

Of direction finding of

Whistlers A-1304

Sweep frequency pulse techniques A-10, 146, 181

Sweep frequency recorders

A-263

Synchronized transmitter and

receiver A-362

(TE) Trans equatorial propagation

A-31, 321, 1261, 1262

Technical problems, general

A-310, 1036, 1243,

1354

Teleprint A-329

Television A-708, 1194

Temperature A-667, 893, 925

Thunderstorms A-25, 158, 297,

584, 585, 892, 1039,

1065, 1082, 1094, 1180

Topography A-423

Transmission blocking A-1051

Transmitters

LF pulse transmitter A-1297

Power pulse transmitter

A-212

Triple split (See Spread F)

Tropical propagation A-244

Troposphere A-137, 377, 423,

440, 541, 644, 645 (See

Subject Outline, p. xviii)

True height of layer techniques

A-85, 151, 187, 202, 842,

1364

Tuned amplifier method A-1197

UHF (300-3, 000 Mc, 10-ldm ) A-27, 51, 356, 366, 404,

498, 621, 768, 836 (See

Subject Outline, p. xvi)

Upper air wind measurement

methods A-32, 127, 290,

318, 404, 405, 817, 853,

1372

Krautkramer's method A-519,

522, 524

Meteor methods A-801

Upper winds A-519, 522, 524,

691

UV - energy A-432, 496

Vertical incidence measurement

equipment A-1308

VHF (30-300Mc, 10-lm ) A-31, 94, 104, 114, 123,

134, 139, 145, 165, (See

Subject Outline, p. xv)

Virtual height A-964

Visual radio reception method

of atmospheric conditions

A-828

VLF ( 30kc, 100-lOkm ) A-25, 102, 103, 105, 204,

229, 230, 235-238 (See

Subject Outline, p. xv)

Wave guide modes A-271

Weather A-425, 1080

Weather forecast methods

Gherzi's method A-462, 463

Whistlers A-21, 272, 322, 355,

376, 380, 442, 447 (See

Subject Outline, p. xxii)

Whistler equipment A-1201

Whistler mode transmissions

A-380

Wide -deviation reaction modulator equipment A-768

Winds A-692

Z-hole A-396

U. S. DEPARTMENT OF COMMERCE

Luther H. Hodges, Secretary

NATIONAL BUREAU OF STANDARDS

A. V. Astin, Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of ihe National Bureau of Standards at its major laboratories in Washington, D.C., and Boulder,

Colorado, is suggested in the following listing of the divisions and sections engaged in /technical work. Tn general, each section carries out specialized research, development, and engineering in the field indicated by its title. A brief description of the activities, and of the resultant publications, appears on the inside of the front cover. WASHINGTON, D.C.

Electricity. Resistance and Reactance. Electrochemistry. Electrical Instruments. Magnetic Measurements.

Dielectrics. Metrology. Photometry and Colorimetry. Refiactometry. Photographic Research. Length. Engineering

Metrology. Mass and Scale. Volumetry and Densimetry. Heat. Temperature Physics. Heat Measurements. Cryogenic Physics. Equation of State. Statistical Physics.

Radiation Physics. X-ray. Radioactivity. Radiation Theory. High Energy Radiation. Radiological Equipment.

Nucleonic Instrumentation. Neutron Physics.

Analytical and Inorganic Chemistry. Pure Substances. Spectrochemistry. Solution Chemistry. Analytical

Chemistry. Inorganic Chemistry.

Mechanics. Sound. Pressure and Vacuum. Fluid Mechanics. Engineering Mechanics. Rheology. Combustion

Controls. Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Polymer

Structure. Plastics. Dental Research. Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion. Metal Physics"

Mineral Products. Engineering Ceramics. Glass. Refractories. Enameled Metals. Crystal Growth.

Physical Properties . Constitution and Microstructure. Building Research. Structural Engineering. Fire Research. Mechanical Systems. Organic Building Materials,

Codes and Safety Standards. Heat Transfer. Inorganic Building Materials. Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics.

Data Processing Systems. Components and Techniques. Digital Circuitry. Digital Systems. Analog SystemsApplications Engineering.

Atomic Physics. Spectroscopy. Radiometry. Solid Slate Physics. Electron Physics. Atomic Physics.

Instrumentation. Engineering Electronics. Electron Devices. Electronic Instrumentation. Mechanical Instru- ments. Basic Instrumentation. Physical Chemistry. Thermochemistry. Surface Chemistry. Organic Chemistry. Molecular Spectroscopy. Molecular Kinetics. Mass Spectrometry. Molecular Structure and Radiation Chemistry.

• Office of Weights and Measures. BOULDER, COLO.

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties of Materials. Gas Liquefaction.

Ionosphere Research and Propagation. Low Frequency and Very Low Frequency Research. Ionosphere

Research. Prediction Services. Sun-Earth Relationships. Field Engineering. Radio Warning Services. Radio Propagation Engineering. Data Reduction Instrumentation. Radio Noise. Troposphcric Measurements.

Tropospheric Analysis. Propagation-Terrain Effects. Radio-Meteorology. Lower Atmosphere Physics.

Radio Standards. High Frequency Electrical Standards. Radio Broadcast Service. Radio and Microwave

Materials. Atomic Frequency and Time Interval Standards. Electronic Calibration Center. Millimeter- Wave

Research. Microwave Circuit Standards. Radio Systems. High Frequency and Very High Frequency Research. Modulation Reseaich. Antenna Research. Navigation Systems. Space Telecommunications.

Upper Atmosphere and Space Physics. Upper Atmosphere and Plasma Physics. Ionosphere and Exosphere

Scatter. Airglow and Aurora. Ionospheric Radio Astronomy.
NBS