bluuebunny/crossref_metadata_2025_split huggingface dataset:
Huancayo Magnetic Observatory April to September, 1946
Authors: Ledig Paul G. 
Published: February 2008

(Latitude 12° 02′.7 S., longitude 76° 20′.4 or 5h 01m4 W. of Gr.)April 22–24—Along but moderate magnetic storm began on April 22 at 06h 58m GMT with a sharp increase in H of 43 gammas in four minutes, and was followed for about 26 hours by minor disturbances characterized by small, rapid peaks and bays. A general increase in H began at 09h 20m, April 23, with somewhat larger but still rapid peaks and bays, coming up to a low maximum at the usual midday period and then followed by a long, jagged decline lasting all afternoon and ending with a minimum of 298 gammas below the base‐line at 23h 42m. After this the storm gradually died out with moderate, slow peaks and bays during a slow increase in H for another twelve hours on April 24. D and Z showed only mild activity during only the daylight hours of April 22 and 23.
Hermanus Magnetic Observatory July to September, 1946
Authors: van Wijk A. M. 
Published: February 2008

(Latitude 34° 25′.2 S., longitude 19° 13′.5 or 1h 16m9 E. of Gr.)July 3—A minor disturbance began with a small “sudden commencement” at 0lh 21m GMT, July 3, and continued until about 17h.
Committee on Geophysical Sciences of the Joint Research and Development Board (U.S.A.)
Authors: Piggot C. S. 
Published: February 2008

The first and organizational meeting of the Committee on Geophysical Sciences of the Joint Research and Development Board was recently held in Washington, D.C. This Committee was established by the Joint Research and Development Board to assist the Board in carrying out the provisions of its Charter in those departments of scientific research lying within the geophysical sciences. These include the following:Physics of the upper atmosphere in the region where cosmic rays and ultra‐violet light are of considerable significance and in which long‐range rockets and possibly jet‐planes will attain great speeds.
Sitka Magnetic Observatory October to December, 1946
Authors: Campbell Joel B. 
Published: February 2008

(Latitude 57° 03′.0 N., longitude 135° 20′.1 or 9h 01m.3 W. of Gr.)October 26–27—A moderately disturbed period began rather slowly at about 04h GMT, October 26, and was characterized by long‐period oscillations until about 15h of the same date when activity nearly ceased. However, at about 23h there appeared short‐period, low‐amplitude oscillations which soon became superposed on rather large bays. A maximum of disturbance was reached between 08h and 15h GMT, October 27, when K‐indices of 9, 8, and 7 were recorded. The traces for several days following this moderately severe storm showed signs of slighter disturbances.
Diurnal variations of computed electric currents in the high atmosphere
Authors: Sucksdorff E. 
Published: February 2008

This investigation is based on the supposition that the observed departures of the geomagnetic force from a mean value are caused by infinite electric line‐currents, or at least very narrow ones, which flow across the meridian. It has been done according to a simple trigonometric method.The departures of the components of the magnetic force in a vertical geographic meridian plane through the station are expressed by ΔX and ΔZ. The ratio (ΔX/ΔZ) = tan α in which α stands for the angle between the resultant vector and the downward direction, which is the same as the elevation‐angle of the supposed line‐current in the meridian plane above the horizon. Thus the direction towards the current is determined. From the positive or negative sign of ΔX and ΔZ it can be concluded whether the current flows to the north or south of the station and whether its direction is eastward or westward.
Needs of Geophysical Service in Austria
Authors: Toperczer M. 
Published: February 2008

As leader of the Geophysical Service in Austria, I now take the opportunity to enter into communication with colleagues in countries which have not been devastated by the war. I turn to you with the request for your assistance in scientific connections, and, if possible, I add the request for support of my coworkers in a material sense.As a direct result of the war the Geophysical Service here has been especially hard hit in its installations. It has suffered the loss of almost all of its difficultly replaceable special equipment. The magnetic base‐station was completely destroyed. We also lack all the recent scientific literature.
Apia Observatory October, 1946, to March, 1947
Authors: Beagley J. W. 
Published: February 2008

(Latitude 13° 48′.4 S., longitude 171° 46′.5 or 11h 27m.1 W. of Gr.)October 8–10—A mild disturbance emerged at 17h 24m GMT, October 8, and continued until 00h 13m, October 10. Movement was irregular. A negative bay during the second three‐hour period, October 9, gave the maximum K‐index 5,
Watheroo Magnetic Observatory January to March, 1947
Authors: Wood F. W. 
Published: February 2008

(Latitude 30° 19′.1 S., longitude 115° 52′.6 or 7h 48m.5 E. of Gr.)January 4–5—A sudden commencement was recorded at 11h 18m GMT, January 4. The horizontal intensity increased by 41 gammas in one minute, west declination decreased by 1′ and then increased by 4′, while the vertical intensity showed a sudden decrease of 3 gammas followed by an increase of 16 gammas. H dropped fairly sharply by 69 gammas in the next hour, whereas D and Z recovered their original values within about ten minutes of the commencement. For the next eleven hours all elements showed large irregular movements without departing appreciably from normal values. From 22h 30m, January 4, until 04h, January 5, conditions were quiet. Moderately disturbed conditions prevailed again from 04h onward, with small, rapid fluctuations at first followed by large, slow swings which died away by about 22h, January 5. At this stage the elements were practically normal again. However, conditions were a little unsettled for a further period of about twenty hours. Ranges: D, 14′; H, 83 gammas; Z, 86 gammas.
Polar radio disturbances during magnetic bays
Authors: Wells H. W. 
Published: February 2008

Comparison of ionospheric and magnetic records at College Observatory, College, Alaska, shows very definite ionospheric effects during magnetic bays. High absorption producing partial to complete radio blackouts was coincident with each of 69 significant magnetic bays which were examined for the period January to September, 1942. The radio absorption is limited to duration of the magnetic bay, thereby establishing a direct relationship which is unusual in magnetic‐ionospheric investigations.Strong absorption of radio waves associated with complete disappearance of all signals is often encountered in the polar regions. This condition is known to become more pronounced during periods of magnetic and ionospheric disturbance. Continuous operation of the Observatory at College, Alaska, near the zone of maximum auroral and magnetic activity, has revealed important information concerning ionospheric characteristics and radio wave‐propagation in polar regions. College Observatory was established in 1941 by the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, in cooperation with the University of Alaska. It was operated by the Carnegie Institution of Washington until 1946 with support of the National Defense Research Committee, Navy Department, and the Wave Propagation Committee of the Joint Communications Board. Since 1946 operation was continued by the University of Alaska under contract with the Central Radio Propagation Laboratory of the National Bureau of Standards. The general program includes continuous ionospheric recordings over a wide range of frequencies, signal‐intensity recordings on high‐frequency broadcasting stations, magnetic observations, auroral studies, and special direction‐finder operations.
Graphs of the induced magnetic moment and shielding effect of a spherical shell in a uniform magnetic field
Authors: Tuckerman Bryant 
Published: February 2008

This paper presents graphs of well‐known formulas for the induced magnetic moment and shielding effect of a spherical shell of constant permeability introduced into a uniform magnetic field. The problem is of interest in the theory of the deviations and compensation of the magnetic compass, and in the shielding of electromagnetic instruments from external magnetic fields.Barlow [see 1 of “References” at end of paper] in an experimental investigation of the deviations of a compass produced by spherical balls and shells, concluded, “... the tangents of the deviation are proportional to the cubes of the diameters, or as the 3/2 power of the surface, whatever may be the weight and thickness... . This law, however, I have since found to have its limits; ... the magnetic fluid requires a certain thickness of metal, exceeding 1/30 inch, in order effectually to develop itself, and to act with its maximum of effect.” The latter conclusion was based on work with ten‐inch spheres.
Hermanus Magnetic Observatory
Authors: van Wijk A. M. 
Published: February 2008

(Latitude 34° 25′.2 S., longitude 19° 13′.5 or 1h 16m.9 E. of Gr.)April 2–3—Small crochet‐type deflections on the D‐ and Z‐traces at 10h 15m.5 GMT, April 2, were followed by abrupt changes in all three elements at 15h 01m.5, April 3. The mild disturbance which ensued, died away at about 24h, April 3.
K‐indices and sudden commencements, July to September, 1947, at Abinger
Authors: Jones H. Spencer 
Published: February 2008

I enclose the list of K‐indices of geomagnetic activity at Abinger for July to September, 1947, in Table 1.In view of the interest which is now attached to “Sudden‐Commencement” phenomena, I append in Table 2 a list of the times at which these characteristic movements have appeared on the Abinger traces during the same period. The time is “Universal Time” (UT = GMT). An asterisk (*) indicates that the movement, though abrupt, was not characteristically “sudden.”
Summary of the year's work, to June 30, 1947, Department of Terrestrial Magnetism, Carnegie Institution of Washington
Authors: Tuve M. A. , Harradon H. D. 
Published: February 2008

This first year of post‐war operations marks a major change in the activities of the Department, with the completion of the observatory and field‐party work of the world magnetic survey.Much of our effort in the past has been concerned with obtaining and interpreting large numbers of observations on the magnetic and electric conditions of the Earth. During the first two decades after 1904 the Department was occupied with a world survey of the Earth's magnetic and electric fields, using the Galilee and the Carnegie to cruise all the oceanic areas, and organizing parties on land to occupy thousands of stations scattered over every continent and in the Arctic and Antarctic. At the end of World War I plans were inaugurated for establishing a number of observatories, to be located at the special sites needed to round out at least a rough approximation of a world coverage, in order to make systematic studies of the variations of the Earth's magnetic and electric fields and other related quantities, particularly in relation to solar effects and magnetic storms. Only two of the list of projected observing stations were established, one at Huancayo, Peru, and the other at Watheroo, Western Australia, but these were fortunately the most vital locations needed for a reasonable world picture. Largely by reason of the extensive and accurate observations made at these stations, comprehensive treatments of the daily, yearly, and sunspot‐cycle effects on the electrical currents in the upper atmosphere and in the Earth's crust have been made during the past 20 years, and many new facts brought out, especially in relation to magnetic storms and other aspects of solar activity. The addition of new analytical procedures based on the technique of observing echoes from radio‐pulse transmitters, first demonstrated by the Department's laboratory group in 1925, gave quantitative information of great significance, and this work was expanded into world‐wide activities of the Armed Services of many nations and all agencies concerned with radio communication. Numerous other cooperative activities, concerned with seismology, meteorology, cosmic and auroral rays, and other solar disturbances have fitted naturally into this program. The original planning for this observatory‐program contemplated the integration of our stations into the scientific life of their local areas, and the expected transfer of our activities to local sponsors at the end of 25 years.
Watheroo Magnetic Observatory July to September, 1947
Authors: Wood F. W. 
Published: February 2008

(Latitude 30° 19′.1 S., longitude 115° 52′.6 or 7h 43m.5 E. of Gr.)(Latitude 30° 19′.1 S., longitude 115° 52′.6 or 7h 43m.5 E. of Gr.)
Zô‐Sè Observatory July to December, 1947
Authors: Burgaud M. 
Published: February 2008

(Latitude 31° 05′.8 N., longitude 121° 11′.2 or 8h 04m.8 E. of Gr.)July 17—A preliminary beginning, at 10h 37m GMT, July 17, was followed by a second greater one, amounting to 70 γ, at 17h 50m. The disturbance was a moderate one, lasting one day. Maximum range was 160 γ andwas recorded during the first three hours of the perturbation.
Hermanus Magnetic Observatory July to December, 1947
Authors: van Wijk A. M. 
Published: February 2008

(Latitude 34° 25′.2 S., longitude 19° 13′.5 or 1h 16m.9 E. of Gr.)July 16–18—Bays of K‐index 3 began abruptly on all three traces at 01h 08m GMT, July 16. These were followed by small “twitches” in the records at 10h 38m, July 17, and finally by a storm of considerable intensity, beginning with a sudden commencement at 17h 49m (H, 56 γ). During the first two hours of the disturbance, small irregular oscillations were super‐imposed on the larger movements. The seventh three‐hour period of July 17 yielded a K‐index of 8. The ranges of the storm were as follows: D, 26′.2; H and Z, 217 γ. While recovery commenced soon after H had reached its minimum value at 15h 11m, July 18, it would be difficult to say exactly when the storm ended, as small disturbances continued almost without interruption until the end of the month.
Magneto‐ionic measurements at high latitudes
Authors: Scott James C. W. 
Published: February 2008

Measurements of F2‐layer critical frequencies for z‐, o‐, and x‐modes at Clyde River Baffin Land, on the assumption of the law

math image
indicate large diurnal and seasonal variations in the magnetic field. Superimposed on these periodic changes a drop of 20 per cent in apparent field occurred in February, 1946, which persisted through September. The variation of gyro‐frequency with height is greater than would be expected from the inverse‐cube law and the law
is not confirmed.
“True”‐reading magnetic compasses
Authors: May W. E. 
Published: February 2008

On one occasion, during the late war, a young officer in command of a British motor torpedo boat demanded that the Naval Store Officer should supply him with a compass in which the card was mounted askew on the needles so that it should read true instead of magnetic. He appears to have overlooked the fact that the variation differed through about 5° in the area of his possible operations and probably thought that his idea was revolutionary. Actually, the idea has often been proposed and sometimes adopted.Already, by the Fifteenth Century it was known that the compass‐needle did not point truly to the North Pole but erred by an angle which later became known as the variation. The navigators of the day were not very clever at mathematics and someone hit upon the idea of off‐setting the needles from the fleur‐de‐lys, which indicated the north point of the card, by the amount of this variation. The idea seems to have caught on among the compass‐makers of the northern and western coasts of Europe but, unfortunately, the variation not being the same everywhere, all did not adopt the same angle of slew or “set of the compassé” as it was called [see 1 of “Authorities quoted” at end of paper]. It followed that, if compasses made in different localities were used together, the ignorant sailor might be confused by the difference between them.
Alexander Ogg, 1870–1948
Authors: van Wijk A. M. 
Published: February 2008

The death occurred in Johannesburg on February 24, 1948, of the well‐known South African scientist and geomagnetician, Dr. Alexander OggAs a result of some fifty years of research work of first‐rate importance, Dr. Ogg enjoyed a world‐wide reputation as a physicist. In the country of his adoption his outstanding services were widely acclaimed, and it was said of him in 1936, on the occasion of his retirement from the chair of Physics at the University of Cape Town, that to him more than any single man did South Africa owe the extent and high quality of physical research which is being carried out in the Union.
Thunderstorm electricity
Authors: Workman E. J. 
Published: February 2008

A recent article by G. C. Simpson [Terr. Mag. 53, 27–33 (1948)] described the remarkable “mirror‐image effect.” The effect is illustrated by curves which show that the current from a needle point placed 8.4 meters above the ground at Kew Observatory was negative (that is, a negative potential‐gradient existed) when the charge on precipitation particles reaching the ground was positive, and vice versa.Much less refined measurements made by investigators from the New Mexico School of Mines, Research and Development Division, in the spring of 1947 at the top of Sandia Mountain (altitude 10,700 feet) near Albuquerque, New Mexico, yielded similar results. A Wilson electrometer connected to the inner surface of an Erlenmeyer flask having the neck removed and the inner surface sputtered with a transparent but electrically conducting surface of gold was used for the measurement of particle charges. A generating‐voltmeter‐type field meter was used for potential‐gradient measurements. Only qualitative field measurements were sought.
College Magnetic Observatory April to June, 1948
Authors: Cleven Merril L. 
Published: February 2008

(Latitude 64° 51′.9 N., longitude 147° 49′.3 or 9h 51m.3 W. of Gr.)April 22—A moderate magnetic storm began gradually at about 00h GMT, April 22, and continued until about 18h on the same day. The most severe part of the storm occurred during the sixth hour and the thirteenth hour when K‐indices of 6 were recorded.
Witteveen Magnetic Observatory January to March, 1948
Authors: van Lohuixen H. P. Th. 
Published: February 2008

(Latitude 52° 48′.8 N., longitude 6° 40′.1 or 0h 26m.7 E. of Gr.)January 1–3—There was a period of magnetic activity with only temporarily moderate disturbances in the evening and late in the afternoon. One K‐index of 5 occurred in the last three‐hour period of January 1; between 18h and 21h GMT, January 2, a K‐index of 6 was noted. After 10h 45m, January 3, a moderate disturbance gradually increased, giving rise to one K‐index of 6 and one K‐index of 5, respectively, in the seventh and the sixth 3‐hour intervals. At about 21h, January 3, the disturbance had ended.
Alibag Magnetic Observatory April to June, 1948
Authors: Rao M. P. 
Published: February 2008

(Latitude 18° 38′.3 N., longitude 72° 52′.3 or 4h 51m.5 E. of Gr.)April 6–7—A moderate storm began suddenly at 03h 58m GMT, April 6, with an increase of 32 gammas in H, a decrease of 7 gammas in Z, and an increase of westerly D by 0′.5. The elements were fairly steady till 16h 49m, when sudden changes in the elements were recorded: H increased by 26 gammas in four minutes, Z decreased by 6 gammas, and westerly D increased by 0′.6. Large‐amplitude oscillations were recorded in all the elements for about five hours after this. The storm ended at about 21h, April 7. Only two three‐hour K‐indices of 5 were obtained during the storm. Ranges: H, 155 gammas; Z, 54 gammas; D, 4′.4.
“The non‐cyclic effect” und “Die Erdmagnetische Nachstörung”
Authors: van Bemmelen W. 
Published: February 2008

Da ich meine, dass ein Referat nur wenig die Grenzen einer Inhaltsbesprechung überschreiten darf, will ich die Arbeit des Herrn Chree im Zusammenhang mit meinen Resultaten hier gesondert behandeln. Im Jahre 1895 erschienen unsere Schriften fast gleichzeitig und gänzlich unabhängig von einander. Da Herr Chree diese Sache weiter verfolgt und meine Arbeit nur mit einigen Zeilen oberflächlich berührt hat, Herr Ellis in seinem “Appendix” meine Untersuchungen nicht erwähnt, kommt mir eine nähere Besprechung in dieser Hinsicht nicht überflüssig vor.Das Material des Herrn Chree leidet an dem Uebel, dass es nicht in steter Uebereinstimmung mit dem Forschungs‐Ziele und den‐Resultaten gewählt wurde, sondern dass es ein im Voraus gegebenes war. Wozu dienen denn die umständlichen Publicationen der magnetischen Observatorien, wenn man sich nur an die teilweise bearbeiteten Beobachtungen seines eigenen Observatoriums hält?
Account of a comparison of magnetic instruments at Kew Observatory
Authors: Chree C. 
Published: February 2008

Last July, M. T. Moureaux, of the Pare Saint‐Maur Observatory, near Paris, brought over to England the traveling instruments employed in his magnetic survey of France, and a comparison was made between these and the standard magnetic instruments at Kew Observatory. At the expressed desire of the Kew Observatory Committee, I submit on their behalf a brief account of the comparison and its results.The comparison serves to connect the standard instruments at Kew Observatory with the standard French instruments at Pare Saint‐Maur, the latter, as M. Moureaux has had the goodness to inform me, being in excellent agreement with his traveling instruments. Pare Saint‐Maur may be regarded as the base station for M. Moureaux's great survey of France and Algeria, while Kew Observatory performed a similar function in the surveys of Great Britain and Ireland, by Professor Rücker and Dr. Thorpe. The existence of the English Channel introduces uncertainty into any conclusions based on the trend of the magnetic lines in France and England, and the instruments employed in the two countries are sufficiently dissimilar to justify skepticism as to their close agreement in the absence of direct experiment. The interest of the comparison is thus far from being limited to the two observatories most immediately concerned.
The magnetic condition of the Earth expressed as a function of the time by V. Carlheim‐Gyllensköld
Authors: Schmidt Adolf 
Published: February 2008

It is doubtless generally recognized that all attempts hitherto made to express the secular variation of the magnetic elements by means of formulas were in the nature of preparatory or preliminary investigations. The derived formulae, invariably referring to particular stations, were purely interpolation formulae, the apparently simple law revealed in general by the formulae being the only fact of material significance. L. A. Bauer's well‐known thesis, however, in which for the first time a law governing the secular variation over the greater portion of the earth was shown to hold true, marked an important step forward.The natural method to be pursued in a theoretical investigation of the secular variation was clearly indicated in Gauss's analytical representation of the earth's magnetic potential. In this representation, the magnetic condition of the earth was expressed as a function of the geographical coordinates without making any assumptions whatsoever with regard to the distribution of the earth's magnetism (with the exception of the one, fully justified by the results obtained, that the earth's entire magnetic force could be referred to a potential of internal forces alone). This analytical representation then formed the simplest and surest basis for all further theoretical investigations. One step, however, remained—to express likewise the magnetic condition of the earth as a function of the time. The magnetic condition at any time being expressed in the only form suitable, that of solid spherical harmonic functions, the introduction of the time variable could only be accomplished with the aid of a similar series of terms, in which, however, the coefficients would be functions of the time.