APRIL, 1908. 93
ceases of intensiflcation or methods of repeated printing from quick
plates to slow plates.
I n the case of very long sparks, 13k feet, or more, t h e bifurcations are generally directed t o neighboring conducting masses, and are not di- rected to the cathode. I n the case of lightning, masses of clouds a t a
low potential, not lying along the main direction of discharge, are indi- cated by these side Iorking discharges.
Some years ago I showed that an explosion occurs whenever powerful
sparks change their direction in zig zags. The spark passed between a piate of glass and a sheet of parafined paper, and it was found that the paper was perforated at each forking of the discharge. Possibly these
explosions occurring along an extended lightning discharge may be an important element in the phenomenon of the rolling thunder, for the sound of such explosions would arrive at coneiderable intervals apart.
An interesting account of the explosive effect at each turning point of a lightning discharge has been given me by Yr. Hsrvey N. Davis, an in- structor in the .Jefferson Physical Laboratory, and I give I t here, since
it is an account by a skilled observer of both the above explosive effects and ball Ilghtning.
 During the Wth of August, 1906, a large boarding-house on the side
of Mount Moosilauke, in the town of Warren, N. H., was struck by light- ning in an unusually sudden and severe thunderstorm. The path of at least three independent discharges could be traced, but they must have been practically simultaneous, for those who had been caught by the
rain half a mile from the house heard only one sharp report. One of the discharges struck the end of the ridgepole of the barn, and came down the wall to a very obvious ground; and two others landed halfway up the
sloping roof of the nearest part of the house, one of them near, but not
on a dormer window, and the other at some distance from any sort of a projection such as would ordinarily be expected to  draw lightning. I n
each place there was a spot about a foot across where the shingles had been forced outwards, as though by an explosion just, under them, while inside there were two round holes four or flve inches in diameter where the plaster had been blown into the room, leaving the laths completely
bare. The flrst of these discharges travelled down the roof to the eaves, and jumped to the telephone wires, bursting out the shingles again as it left the roof. It happened that one of the young women of the house had just closed the dormer window, and was in the middle of the room with her head clolre to that part of the sloping ceiling where the second of the holes was found. It is possible that this waa merely chance, or, on the other hand, her presence may have had some inflence on the direction of the original discharge; at any rate, the discharge jumped to her right shoulder, and passed through or over the surface of her body
to her left foot, then ran along the floor to the wall, leaving a mark such
as might be made with a hot poker, and flnally reached earth through the side of the house. The young woman was, of course, completely stunned, but was fortunate enough to escape serious injury. An inter-
esting feature of this discharge waa the regularity with which it seemed
to explode every time it turned a corner. The explosions between the
ceiling and the roof have already been mentioned; the next occurred when the discharge reached the womans foot. Her shoe and stocking
were blown completely off, so that only the left half of the upper of the shoe.remained attached to the sole. From her foot it ran along the floor
to a tin pail, which was standing on a piece of linoleum, and here i t ex- ploded again, overturning the pail, and demolishing the linoleum, some of which was found inside a water pitcher on a stand near by, while one
or t w o shreds reached an adjacent windowpane with force enough to stick between t h e glass and the sash. Finally, the point where the
lightning reached the wall and started down between the sheathing and plaster was very plainly marked on the outside of the house, a couple of clapboards being forced out several inches. In the mom below, the
plaster was loosened from the laths all the way down, probably by the pressure of the heated air, but the appearance was quite daerent from that of the ceiling in the room above. Fortunately nothing took flre.
A t the time of the discharge the guests were in the dining-room at the other side of the house, and several of those who turned most quickly saw slow moving ball discharges just outside the window. *One of those with whom I talked, a trained scientist, was sitting with his back partly turned, and saw only one ball of flre, llke a glowing coal; but others said that it had been preceded by one rather larger, perhaps as large as a baseball. When he flrst saw the second ball, i t was three or four feet
from the ground, and was falling obliquely, aa though it had rolled off the roof of a low ell near by, and its velocity was only a few feet per
second, certainly not enough to leave a streak on his retina, as he noticed at the time. We searched that night, and again carefully the next day,
for traces of these discharges in the ground, but could flnd none. Whether they were independent discharges from the main cloud, or
were secondary effect, due to the electrification of the wet roof, I do not know. At any rate, they were not immediately connected with either
of the three main discharges, for two of these went to obvious grounds,
aa has been indicated; and the telephone wires, which aarried off the
third, were nowhere near the part of the house where these balls were seen.
I * * I + I *
* * * + +
14-2
In long discharges of lightning these explosions, directed at varied angles, could give rise to sound waves, which, starting practically at the
same instant, nevertheless, by diEerent angles and degrees of reflection, could arrive at the ear of the listener at considerable intervals, and pro- duce the rolling of thunder.
What, then, are the conclusions that can be drawn from the foregoing manifestations of electric discharges which can be produced by a large
number of storage cells ? The first fact which impresses one is the im- portance of the consideration of amperage as well as electromotive force.
Throughout scientific literature, and in popular conception, electromo- tive force has received the chief consideration in discussing the phe-
nomena of lightning. Experiments in laboratories have been conducted with electrical machines which are generally incapable of affording much
current. Franklins experiment with t h e aid of a kite illustrates an un-
derestimate of the current in a lightning discharge. Even to-dayno one would think of repeating Franklins celebrated experiment, largely from a dread of voltage, but with little conception of the possibility of danger from small voltage and large current. We are beginning to realize, however, that 500 volts, accompanied by a current of from 10 to 20 amperes, is sufficient t o destroy human life. One compartment of the storage battery which I have described in this memoir-a compart- ment affording something over 800 volts-short-circuited through the
body of the janitor of the laboratory, was sulficient to knock him sense-
less. The most powerful electric discharge which we can produce by modern
appliances in a faint shadow of lightning-so faint that i t fails to repro- duce in most essential respects the phenomena in the heavens. I have never been able, by the use of resonant tuhes or other arrangements, to cause reverberations to reproduce in the slightest degree, even with sparks six feet in length, the rolling of thunder. The energy of an or- dinary lightning discharge must be enormous.
The forms of lightning discharges are very varied, and when one asks whether lightning is oscillatory, one should specify the kind of discharge.
A COLLEUTION OF MEAN ANNUAL TEMPEBA-S

FOR MEXIUO AND CENTRAL AMERICA.
By PHILIP P. CALVERT, Ph. 1). Assistant Professor of Zoology, University of Pennsyl- vania, Philadelphia, P a
In studying the distribution of the Odonata, or dragonflies,
of Mesico and Central America, particularly with reference to
temperature, the writer prepared a colored map illustrating the
distribution of mean annual temperatures in those countries.
This map is shortly to appear as a plate in the Biologia Cen-
trali-Americana volume Neuroptera (London). It is based
partly on two similar older maps, partly on a body of
temperature data specially gathered from many scattered
sources in the libraries of Philadelphia and of the United
States Weather Bureau at Washington. As these data will
probably be of use to climatologists and others, they are here
brought together in tabular form. Since the authorities cited
for temperature records often give other climatio data also,
the column ccAuthority for temperature records  will also
serve as a selected bibliography on meteorological phenomena
in these countries. In the search for the earlier authorities
much assistance was derived from Sr. Aguilar y Santillans
Bibliografia Meteorologica Mesicana  in the Memorias de
la Sociedad Cientifica Antonio Alzate, IVY p. 5-47, 266-276,
1890. The student of Mexican temperatures will also find Sr.
J. Guzmans L c Climatologia de la Repfiblica Mexicana desde el
punto de vista higihnico  in the same Memorias, XX, p. 181-
11. A map, 97 by 71.5 centimetercin the library of the Academy of Nai ural Sciences of Philadephia, inscribed merely Carta Olimatologica.
Sebastian Reyes. P. J. Senties. ,+. Donamette Imp. Escala de 1:3,000,000. G r a d e chez Monrocq fr. Paris. Thanks to the Secretaria de Estado y
del Despacho de Fomento, Colonizacion e Industria of Mexico, I am in-
formed, under date of July 30, 1907, [que dicha Carta fu6 publicada en 1889 por disposicion de esta Secretaria, haciendo loa trabajos relativos 10s Sres. Pedro J. Senties, que era Director de la Escuela Nacional de Agrlcultura y Comisionado de M6xico en 1s Exposicion de Paris del
mismo aHo y Sebastian Reyes que fu6 Profesor del Plantel antes men& onado. This map was reproduced without alteration, but on a reduced
scale (1:6,000,000), in Tomo XI, Andes del Ministerio de Fomento de la
Republica Mexicana, Mex., 1898. 2. A map entitled  Reparticion de la Temperatura en la Repdblica Mexicana for the 6 ABo Meteorol6gico de 1902, published as Planche 16,
Boletin Yensuel, Observatorio Meterol6gico-Magnetico Central de YBx- ico, Noviembre, 1902. Seilor Don Manuel E. Pastrana, Director of the
Observatorio, has kindly informed me (September 6, 1907) that the m a p
for later years have not yet been published.
94
1901.1902 ...... ............... ............... .............. ............... ............... ............... ............... ............... ............... ............ ............... ............... ..............
MONTHLY WEATHER REVIEW .
TABLE I.--dlean annual tenrpercrturez in Mkxim .
BOM 1901 and 1902 . CRM II, p . 186.
CRM 11. p . 134 . CRMII,p.136.
CRM 11. p . 184 .
CRM 11, p 1% .
Do . Do . Hano .
Do . Do .
Do .
Do . Do .
APRIL. 1908
*i Acapnlco ................... Acayucan .................. Actopan ........................ Acula .......................... A dimtea ............ A&lahua ................. A l v t r d o ....................... Antigua, La ................... iEYpan an ........................ Axocuapan ................... Cstemaco ..................... Chaultian uis ................
Chtcontepec .................... Chihuahua ................. Chontln .................... coatepac ..................... Coatsrcoalcos .................. Do ......................... Colima ..................... Do .......................
.....................
ChiCOnlN8 ... : ...............
c U r .................... Cord0 a ........................ Do ........................ Caamdoapan .................. Cmcomatapec ................... Cosquihui .................... Guernavaca ................
Culircpn ...................
Quad gara ...............
Guanajua to ................
Gua rnan .................. GutLrrez Zamora ......... Huatuseo ...................... Hun acocotla ..................
IxhuWan ......................
Duranf ....................
Hu&tla ................... ~~a m a t l a n ..................
Ixhuatlan ...................... Ixtncornitan ............... Jalacingo .................. Jld;p,,n ........................
Jicaltepec ...................... Juchique ....................... Lagon ..................... Leon .......................
Lerdo, Cludad ............
L i n w s ...................
%o ..................... Mdtrata ................... Martinez d e b Torre ......... Mata~oms ................ Mazatlan .................. Meca apan ................. MedIln ...................... Merlda ....................
Mexico City ................ Minatitlau ................. Mirador .......................
Yisantla ......................
Monterey ..................
Morella ...................
Naollnco ................... Naranjal ...................... Nautla ......................... Nogales .................... Oar.ca .....................
Orisaha ....................
....................
h h dells .................
I
Looality .
Guerrero ................. ,
Vera Crux .............. .do ................... .do ................... Aguaacalientes ........... Vera Cruz ................ do ................... .do .... ! .............. ..do ................... .do ................... ..do ................... .do ................... .do ...................
.do ................... Chihuahua ............... Vera Cruz ................ do ................... .do ................... .do ................... C o l i ~a ................... ..do ...................
vera CNX ................ do ................... .do .do ................... do ................... ..do ................... Morelos ..................
Slnaloa ................... Durango ................. Jalisco ....................
Guanajunto ..............
Sonora .................. Vera Cruz ................ .do ................... do .................. Eidal o .................. vera 8ruz ................ .do .................... .do ................... Chiap an .................. Vera Cruz ............... do ................... .do ................... .do ................... .do ................... Jaliseo Guandua to ..............
Durango .................
Nuevo Leon ..............
souora ................... Vera Cruz ............... ..do .................. Tamaulipas .............. Sinaloa .................. Vera Cruz ................ ..do ................... Yucatan .................
Distrito Federal ......... Vera Cruz ................ ..do. ...................
..do.. ..................
Nuevo Leon ............ : .
Michosean ...............
Vera Crnz ................ ..do.. ................. .do .................. Sonora ................... Oaxwa .................
Vera Cruz ................
.do ...................
...................
...................
VerPCNZ ................ . 1891. 1897 ...... ............... ............... ............... 1880-1903 ....... ...............
. . . Romero. p 39 MWR 1897 CRMII. 11 . 134 . CRM 11. P . 185 . Hann . BOM 1901. 190 and M S.
CRY 11. P . 1 1
Catitude north .
............... 1$%%1898.1900-
1877-1902 ......
1W-1870 ...... .
isge.iss9.iw! . 1894-1m ......
1902 .
................
............... ................
................ ................
0 1
16 60 17 57 19 30 18 30 21 53
19 7* 18 46 19 19* 19 19s 19 47.
18 25 18 1 F
20 58 2838 21 lsr 19 27 * 18 9
19 11
........
I
.........
.........
.........
......... 18 M
18 z, 19 4
18 65
2.4 48 24 1 20 41
21 1
27 56 20 2*
19 9
20 8% 21 9
19 21.
20 41 17 10s 19 49
17 58 20 10 19 60+ 21 21 21 7
25 :j3*
i 94 42 i ! 24 57.! 18 46 30 38 18 4%
2 0 4 25 I
23 11 18 13 19 @ 20 5s
19 26 17 59 19 15
19 E8
2540
19 42
19 x+ 18 49* 20 13 31 20 17 4
.........
.........
........
I
is a2
18 51 18 11. 21 40 2 2 4
22 3* 20 27
25 28
19 17. 19 31 18 57s 19 34 17 60 28 4P 19 2
22 l a
3 36
2 0 7
Do; .
CRM 1,p.Sl; 11. p . 15; MWR.1897; 13nM.1698.1900-
1902. MZ 1897 p 66- BOM. 18961903 .
CRM1I.p 136 . Ham . BOY 1898 1899 1902
1902 . CRM 11. P . 184 . CRMII. P . 195 .
C R ~ 11 P . is Schot t. b t o r i u s Bo1 . SOC . Geog . Estad . Rep . Mex .
BOSa:l895!1902: CRM I. p Iw; It,p.TI; MWR1896-
(2) 1 . p . 367-9 (1669) .
Altitude .
............... 1901-1902 ...... 1879.188b1898, 1 ~1 9 0 5 .
_-
Feet . ........
14 516 1, 020
6. 1M
5 .m 29
I. 181
........
.......
, ....... , ....... 1.305
1. 962
4. 107 6
....... .......
4. 769
.......
........ 1. 601
.......
Do; .
BOM 1901 1902 Reyeb lS& MZ 1896 . 268; 1887.p 385; 1906 p . 47 7. 1906:p4d7; BbY. 1&-1902nndrna. CRMi,p.?Of II . n . 14 .
....... 2. 860
5.209
....... 295
....... 4. 936
111 6 207 5: 186
................ ................ ................ 1878-1889 ...... 1894-1900.19U2.
................
6. 737
....... ....... 4. 408
1 9 %
1. 004
.......
........ ........
689
4. 756 436 341
6 277
5: 901
3. 726
5 087 4: 946
495
49 25 1. 116 171 49
213
........
........
1 . 190
5. 25s
7. 469
3. 293
1. a&
6.
1. 624
caiitii,-p . 184 . CRM 11, p 13 6. CRMII 3 1 .
BOM; 1895-1900,1902, CRMJI, p 135.
BOM l&, p . 3 3 ;p 16~9&;7~ 20, 11, p . 14 .
........ 2. 568
a 857 10
6: 119
Otatitlan ....................... Osuluama ..................... Pabellon ................... Pachuca .................... Panu eo .................... Papantla .......................
Paman .....................
paso de Ovejaa ............ Patscuaro ...... : ........... Perla La ................... P e d ......................... Playa Vicsnte ................. PorErio Dim, Ciudad ...... Puebla .....................
Pueblo Viejo ............... Que retsro ..................
4. 215 161 751
6 311
66 977
423
7: 9M
5. 033
7. oia
8. 085
7. 118
........
312 722
.do ................... .do ................... A uascslientes ...........
Vera ruz ................ .d 0. ..................
Cmhuila .................
Vera Cruz ................ Michoacau ............... Vera Crus ................ .do ................... .do ................... Coahuila ................. Puebla ..................
Vera CNE ................ Queretaro ................
Hfdalp ..................
........ 6. 068
Metera
.
4 1% 311
........ 1.861
1, y ........ ,
360
998
695 1. 8 1
1 .5 2 2
488
........
I
........
I
........ ,
.....
..I
.........
.........
........
I
......... 873
90 1.588
1.505
34 1. 892 1.581
2.060
........ ,
........
I
......... ........ ,
1. ........
I
380
806 310
1. 450 123
la
1.912 1. 799
1. 135
363
1 551 1:508
1. 602 151 15 7.5 340 52 15
2. 277 65
410
495
1. 961
790 8 1 176
........ ........ ,
........ ,
........ ,
1. 00.19
........
1: 561
1. 285 46 2-29 1. 924 2. 426 20 YJ8
1. 554
129 2. 138
2. 465
?. 170
........
95 220
........ 1. 850
b a n annual tern- peratare.
OC . ~-
27.6 24.5 23 0 24.4 18.1 14.8 26.4 24.9 24.8 16.0 16.4 24 . I
9 .8
24 . 1
E . 0
16 . 2 24.0
19.2
26.3 24 . 4
26.1 24.5
19.7 20.5 20.0 24 5 16.8 8. 9 20.5
25.2 17.3 19.7
18 . 1
0 .9
23.2 17.7 12.0 22.7 17.8 13.3 23.4 24.4
1% 9 17.7 26.5 2 .a 21.1
18.2
18.7
2.5 . 1
84.4
18.4
21.7 17.0 23.7 3.2 24.9 22.9 22.0 26.8
15.5 24.1 20.1
2 2 8
21.6
16.8
16.0 21.3 28.1
17.2 20.3
18.2
26.1
25.8 18 . 1
14 6 E . 9 22 . 7
2% 1
16.1 17.0 10.5 24.1
16.9
2S.6
18.1
26 . 4
21 .a
_ .....
OF .
.. .-
SI . 5 76.1 77.0 76.0 64.6 5s . 6 79.6 76 . 6 76.6 60.8 59 . 5
75.7 74.8 75.4 71.6 64.8 73.4 66.6 79.3 76.6 79.0 76.1
67.5 68.9 6% . 0 76.1 65.2
73.2 68.9
77.4 63.1 67.5
81.6
75.0 73.8 63.9
1 .6 7% 9
64.0
55.9 74.1 76.0 57.0 63.9 79.7 12.1 70.0 64 . R
65.7
73.6
7!! . 3
66 . 1
71.0 62.6
74.7 73.8 56.8 73.2 71.6 78.4
60.0 75.4 68.2
18.0
70.7
62.2
60.8
63.0
68.6
fi4.8
77 . 2 74-6 64.6 58.3 73.2 7 2 9
78.6
77.7 61.0 62.6 50.9 75.4 70.3 60.6
74.5
64.6
70.3 7 3. 6
?eriod of observation .
Years . -
1 moa, 5 6 5 2
7 6 4 5 5
7 6 4 5 6 2
6 4
6
12
6
7 5 7 7 7
8 11108,
;
5 2
12
8
1 3 6 4 2
6
5 6 1 4 13 5 2 5
25
1
5,
5 2 6 6 9 23
5 I
7
26 4 16
9 10
3 9
6
6
-2 1 21
6 3 7 12 8 6 5
13 moe
2 1 6 6 4
7 25
7 8
a
Authorlty for temperature records .
Date .
............... 1901.1902 ...... ............... .............. ............... 1899-1w ...... 3869-1890 ...... 1896 1897 1899 .
1a1-1865 ......
i d . id
..............
............... ............... .............. ............... 1873-1874. 1907
.............. .............. .............. .............. .............. 1881 .......... .............. 1895-1907 ..... .............. .............. .............. 187$.189G ..... 1878-1902 .....
1902 .........
............... ...............
Do . BOM 1901. p . 224; 1902. p . 65 . CRM 11. p . 196. CRY 11. p . 184 . CUM 11. p . 186 . MWR 1SY!+1904 . Bnrreto Revista Cien t. Itflex . 1
BOY lSb7.1899.19Op . MS 1901; . Nu . 12 1880. CRM If. p . 14.
CRM 11. p . 134 . Challen r R e p k C R Y I F p 1% CRM 11: p . 186. CRM 11. p 13 4. CRY11 p 185 . Reyes hol Soe . Geo Estadia t. Rep Mex . (Sa).
B o d 1894 1900 his 1891.189 3. BOM 1899 1900: Barcena XnalenMin Fomenta Re Mex I Y
BOM 1889.1895-1899. 1902; CRM I. p . 20.11. p 16.
I V b. 90et aeq . 167% Mf3 1907 .
ni-azi~. 1891 . BO^ ism 189s. idi. i w i ; i& 11. p . 14; MWR 1902 . I 9 d .
BOM 1903. CRM 11. p . 185 . CRM- 11. p . 13 4.
Do.
Do .
Hann . CRM 11. p . 134 .
CRMII 135. MZ1895: 1 . 357 . CRN II,p.134. MS . CRM 11. p . 136 . CRM I I ,p . 185 . Do . Reyes . 1880 . CRM 11, p . 16 . Bo1 . Oba Met. Leon 189 7. lB97-19b2; NdR 1897-l90i? BOM 1902 .
MZ 1897. p . 252; BOM
189ti.1901 ..... .I BOM 1902, p 22
............... DO . 1897-1898 ... MWR 1897 1808 . 11 899 ........... Me% . interk . R . R . Co., 1900 .timetable . ................ CRMII . P . 186 . 1879 ........... Reyes Is80 . ............... 1 p CRM-ii . 1% . ............... uo .
1697-1903 ...... 167s-1902 ...... . de
...............
APRIL, 1908.
! i Rea1de.l Monte ............. I Hidal go... ................
MON!rRIJY wF4ATHEa REVIEW.
TABLE l.-Maan nnnual tsnrperaiura in Mexim-Gontinued.
0 1
20 8
95
9,092
5,379 7
M i t y . 1 Stab.
2,77:
. 1,w
1
Lstitudi north.
8 ' 1889.1894 1896
Illnos 1902 ........... 10' 1888,1889,189c 1900.1902. ... 10 ................ 6 ................ 3 ................ 1 isg?-i~g a..... . 1 1879 .......... 6 ................ 19 i87eim.i8w,
1900, I&.
1894-1897,
19m. 1899,1900,
2 ................ 5 ................ 5 ................
4 ................ 9 ................ 3 ................ 4 ............... 7 ................ 6 ................ 2 18811885 .....
5 ................ 6 ................
6 ................ 6 ................ 1 1879 ...........
3 ................ 6 ................ 6 ................ 9 1894-1902. .....
5 moa 1897,189S1901.
4 1894,11~,1897, 1899.
6 ................
5 ................
BOM 1889, p. 369; 18964900,1902; CRM 11, p 19
BOM 1902. BOM:.1889, p 370,439; 1895-1900, 1902; CRM I, p.
Ha& CRM I I ,p . 136. CRM I1 p.186.
b y e s I&
21. 11, p 16.
MZ, isgb 47s.
C R N ~I 1%
BOM, i& ism 1895-1897 1899, 1900, 1902; MZ. 1894, p. 74; CRh I, p 21; h, p 16.
CRM 11, p. 136. CRM 11, p. 1%. CRM II,p.131.
CRM 11, p. 186.
Romero, p. 88.
CRM I1 155. Hano. h 8 M 1901, 1902.
Mattern Mein. $or. Cien. Antonio AIzrte, I, p. 6 d 1887.
CRM I1 185.
CRM I1 p. 184. Re es 1880.
CRM 11. D. 136.
BOY, 1896,1m7,1899; m n r 11, p. 15
C R M ~I ,~. 1%.
CRM 11, 'p. ia4.
CRM 11' p. 134. CRM 11: 1%.
CRL 11 15% CRM 11: E 1%
Do
SolinaCruz ................ Oavaca .................... 16 10 Saltlllo .................... Coahuila .................. 25 26a
Do ........................ 8pn Andrea Tuxtla ......... 8pn CristobPl Llave ........... San Juan Bautista .......... San Juan del Rio.. ......... San Juan Evangelistr. ..... 8an Luis Potosi ..........
.do. .............................. VeraCruz ................. 18 27
..do.. .................. 18 &V Tnbnsco ................... 17 54
Queretaro.. ............... #1 224 VeraCrue.. ............... 17 63 $an Luis Potosi. .......... 22 9
33 6,481 289
6,201
IC 1,97f I
1,890
Santiago Huatuseo ........ 8antia T u r t l r ................ Santo h k i n g o . ............... Silao .......................
Vera Cruz.. ........................ di, ................... 18 28' .d i ~. .................. 20 18* (3uanajuato ............... 20 5(i
%ledad .................... Tacubaya.. ................ Rmiahua .................
Tantima ................... Tanto uca ..................... Tapseiula .................
Tnnipico.. ..................
Znpotlan ................... 1 Jaliseo .................... [ 19 36
VeraCrna ................. 19 4* Dlstrito I~'edera1.. ......... 19 24
Vera Crnz.. ............... 21 16
Vera Crnz ................ 21 20
do ..................... 21 21 Chiaps ................... 14 645
Tamaulipss ............... 22 16
Zentla ...................... VeraCrue ................. 19 T* Zongolicr ...................... .do.. .................. 18 40
690
7,818
................. 3,995
Altitude.
.................. 180
2,352
1,218
Feet. I Meters.
Tehuipango ............... Tempoal.. ...................... Teocelo ......................... Tepezintla ....................... Tcquiln.. .................... Terlutlan ................ Tlhuatlan. ................. TIncolulan .................... Tlseotalpau. .................. Tlnlixcoyan.. ................ Tolura .....................
Vera Cruz.. ............... 18 81
.do.. ................... 21 28*
do.. ................... 19 2W do ..................... 21 8. ..do.. ................... 18 44* Puebla.. .................. 19 49 Vera Crua.. .............. 20 43 ..do.. ................... 19 59*
..do.. ................... 18 37* ..do.. ................... 18 48 Mexico .................... 19 17
.................. 1,184 1 361
..................
5 389 6:M)l 749
10
275 8,610
5,448
..................
i3E .'422 1,661 8
84
2.625
.................. %5
..................
61061 I '*R4?c
Topolobampo ............. Tuxmn .................... Turtlo Qutirrma.. ......... Vera Cruz.. ................
93
0
0 0
925 m
7 ,F
1
2,523
8inaloa ................... 26 85s VeraCriiz ................. 20 69 Chlapas.. ................ I6 32 Vera Cruz.. ............... 19 12 3
22
2
6
5
24
6
7 6
189&1900.. .... 1791-1803,1817- 1859 1891-1894, 1896' 1902 iw-is40 ...... ................
1878-1900,1902.
1694 1896,1899-
...............
lsd ................ ................
..................
1.74 I 49 I 16
8 030 7iY.13
8,013
6,122
4,107
2,448
2,421
2,4G
1,562
1.452
..................
..................
Mean aooual tem- peratnre.
Veta Grnnde ...............
Yecuatla.. .................... k a k a s ..................
Vigaq Las ................
12 3
28.8
17.6
17.1 24.0 25.1 26.6
18.3 23.5
17. 6
25.6 23.8 1s. 7 19.4
26.8
15.6 24. 2
24.0
23.4
23. U
za 8
14.3 23.6 19.6 2e 9
14.9 16.6 24.4 14.8
25.1 24.7 13.7
23.9 24.8
24.6 25.0
14.1 11.1
41.4 14.3
19.8
21.0
18. 6
Zacatecag ................. .! 22 M)
Zscateeas ................. .j 22 46
Vera Cruz ................ .: 19 381 ..do.. ................... 19 6W
tThia is the revised altitude given by Barcena (Anales Minist. Fomento. VII, p. 380, 1884); a S. Cristobal in the Canton of Vera Cruz, as CRM 11, p. 136,locates it, but in the Canton of Cos% by the maps.
.
OF.
54.1
83.8 63.7
62.8
75.2 77.4 79.9 65.0
74.3 6% 5
78.1 74.8 66.7 67.0
60.0
75.6 76.0
74.2 73.4
57.7 74.3 67.3 73. 2
68.8 60.1 76.0
68.6 77.2 76.5
56.7
75.0 76.6 76 3 77.0
67.4 5 2 0 70.5 57. 7
67.6
69.8 66.6
7a 4
83. a
Period of observation.
Tears. I Date.
' Authority for temperature recorda
-
-I
Do .- BOM 1895 1897 l8W 190&1902- CRM I
IW&tiM~7,,~l9-19O1.
21; TI. p. 1+'%1. ked hetedr. Eutndo'Mex., I& p. 191
BOY 1898-1900. Schoit; BOM, 1902 and ma.
Behott. CRYII 184,
CRM 11' p' 185. BOM. I$& I889,18954900,1902a~d ma; CRM I, p WII 16.
BO& 1&g, 1899-1902, CRM 11, p 14
CRM 11, p. 134
Do
he earlier E ures were 1U95 meters (cf. Eann). iloapan. XNooe of the maps of Mexico show
1 Komero's (p. 36) latitude of 19O 49' fur San Juan del RIO is not supported
288, 1903, and Sr. J. Ramirez's c r La Vegetacih de MQxico "
in Anales del Ministerio de Fomento Rep. Mes. XI, pp. 227
et sep., 1898, of importance. The sources from which the data have been gathered are
frequently indicated in the accompanying tables by abbrevia-
tions whose significance is as follows:
BOM. Boletin Mensuel, Obeervatorio Meteorol6gico-Mag-
netico Central de MQxico. MQxico, 1888, 1889, 1895-1902.
(Data for 1897 are also reprinted in Anales del Ministerio de
Fomento de la Republica Mexicana, Tom0 XI, p. 467489.
Mexico, 1898.)
Challenger Repts. . Bcientific Results of the Voyage of
H. M. 5. ChaUenger. Report on Atmospheric Circulation by
Alexander Buchan, in Physics and Chemistry, Vol. 11, part 5, ~
London, 1889.
CRM. El Clima de la Rep6blica Mexicans por M. Moreno
y Anda y Antonio Gomez. Bfesico Oficina tip. &e la Secretaria
de Fomento.
Eann. Handbuch der Klimatologie von Dr. J. Ham. Zweite
Ausgabe. Bd. 11, p. 286. Stuttgart, 1897.
MWR. The MONTHLY WEATHER REVIEW, United States De-
partment of Agriculture, Weather Bureau, Washington, D. C.
Volumes for 1896-1906.
Afio I for 1895, 1899; Aiio 11 for 1896. 1900.
MZ. Meteorologische Zeitschrift. Wien u. Berlin.
Reyes, 1880, in Boletin, Sociedad de Geografia y Estrtdistica,
Republica Mexicana, 3a Epooa; V, p. 160-181.
Romero. Geographical and Statistical Notes on Mexico.
By Matias Romero. G. P. Putnam's Sons. New Pork and
London. 1898.
Schott. Tables in Smithsonian Contributions to Knowledge
No. 277. Washington, 1876.
Some manuscript records in the library of the United States
Weather Bureau from the Observatorio Meteorolhgico-Mag-
netico Central de M6sico are often quoted as drms." in connec-
tion with BOM. For the privilege of examining these I am
indebted to the officials of the Weather Bureau.
The data for Cuernavaca for 1907 and for Jalapa 1895-1907
are from manuscript recorda from the meteorological observa-
tories at those places, which I owe to the kindness of Sefior
Don M. E. Psatrana, Director of the Central Observatory of
Mexico.
Latitudes and altitudes are taken from the authorities quoted
for the temperatures; the determinations of the Comision Geo-
grdco-Exploradora for the State of Vera Cruz, in Revista,
Sociedad Cientifica 'Antonio Alzate' xxiii, p. 31-32, Mexico, 1905;
Anuario del Observatorio Astronomico Nacionel de Tacubaya
por 1901, p. 270-327 (latitudes only); Doctor Sapper's papers
on Central America in Petermann's Mittheilungen xliii (1897),
1 (1904) und Ergiinzungbinder xxiv (1895) and xxvii (1899);
Mr. Gannett's "List of Altitudes in Mexico and Central and
South America,," Monthly Bulletin, International Bureau of
the American Republics for September, 1904, Washington; and
96
--
0 1
17 30
15 33;
.. __ ........... - ......... - .
I.
a
2,iM
Locality.
Chimax.. ...................... Quatemala City.. ..........
Mercedeq Lss.. ............ Puerto Barrios.. ...........
Quezaltenango ............
&lama ................... Setal.. ..................... Villafrrnca ................
Tegucigalpa
Salvador. Bahia eaterode Jlquillisco~ Barra 6el Lempa.. .............
Jacuaran, Costa de.. .......
Playa del Encantsdo.. ........ Puerto Conmrdia. ......... Puerto de Acajutla.. ....... Puerto de La Libertal.. ... Sau Clalvador. ............. Sants Tech. ...............
Union, La .................
Nicaragua. Bluefields .................. Deaeado, Rio, 10 miles from
Qreytown.. ....................
HOndUVa8.
Caribbean.
Department.
.do .................... Guatemala.. ..............
Quezaltenango. .......... Izabal ...................
Quezaltenango ............
Baja Vera Paz.. ........... Alta Vera Pae.. ........... &spa. ...................
..........................................
Usulutan.. ................ .do ...................
La Uuion .................
..do .................... La Paz. ................... fions~nate.. ............... La Libertad.. ............. San Salvador.. ............ La Libertad.. .............
JA Union ................
Zelaya .................... S. Juan del Norte.. .......
.<la. ...................
British Honduras. Belize .................................................
14 -E*
15 44.
:: $[ 15 8
15 $2
.........
3,280 7
i,io8
3,018
2,:394
2,004
L ss Laa ................. Rivas ..................... O%d (on Rlo 8. Juan, 40
1 S. Juan del Norte.. ....... niiles from C'aribbean).
14 1 9
13 13*
3,200
......... 13 16
;; ;r{ 13 28
I3 19 18 I
IS 26
13 42 13 M*
......... ......... ......... ......... 50
......... 2 099 3:OOl
MONTEUiY WEA!CHER RFAVIEW.
TABLE 2.-Mean annual kvnpraturee in Cmtral America.
12 0.
10 52.
10 6 s
11 2w
10 47*
I1 26;
.........
11 2*
11 8*
11 15*
11 5l*
11 15; 11 25;
9 so*
10 o+
9 51:
9 W*
in n*
........
.........
APBIL, 1908
......... .........
.........
......... .........
209
3 Over
3,300
.........
......... .........
100
110
.........
4,:w9
......... 10
3,tW
ti6
148
.................
2,034
I Altituda
ILivas. .....................
Roes de Jericho, Hacirnd:r
Sabalos Cam (on Rlo 8. Jua11,'26 mires from Lake Nicaragua). &n Carlos Fuerte.. ....... &n Juan del Sur.. .........
6an Uhaldo ................
Latitude north. -. -
1
Feet.
Rivas .....................
Matagalpa ................
Chontales .................
C'houtalas ................ Rivas .....................
Chontrrles.. ...............
S a y .. ................... To a gage station ............. &la Rlca. Agusealiente ...............
Heredia .................... Puerto Limon.. ............ San Jose ...................
Turrinlba .................. Zent. ...................... Panama. Alhpjuela (on upper Chac
Boca, 1.8 (on Bay of Pan-
Do.. ......................
gres Biver).
15 24 4,281
14 88 4,887
Rivax.. ................... ..do.. ...................
Cartago.. .................
Heredia .................. Liuion .................. 5. Jose ................... ..do.. ...................
Cartago ................. Limon.. ..................
............................
............................ ama). Colon (formerly Aspinwall) Do.. GamLma.. Nws (Island near Panama)
............................
............................................. ............................
.............................................
.........I .........
164
1 w2
Y G i I
t The
Meters.
0
850
l,.W
1,000
2,%W
9:n
730
61 1
976
1,490
....... ....... ....... ....... ....... 1s
64U 915
i n
.......
.......
....... .......
61
over i 1,006!
....
........ ........
30
32
........
1, mn
........ 3
1,160
e-w ?il
44
........
.......
........ an!
31
14
Mean annual tem- perature.
-~
0 c. - ..
26. 1
21.3
18.7 18.8
22.7
26.8
14.6
23.1
20.6 23.0
22. B
9 .5
27.5
27.4
27.4 27. b
2fi. 1
26. 1
23.1 il. 6
28.9
26. I,
26.3
26.2
26.6
24.9
26.8
17.2
25.1
25.7 25.1
27.9
26. I; 2i. 1
18. 1
21.1
25.4 21.i 19.7
5.8
1 .5
3 .5
26.2
26 4
28.8
27. 1
pn. 2
~
O F.
-
74.0
7n. a
65. 5
65.0
72.9
@J. 3
58.3
i3. 6
69.1 73.4
79.1
81.2
81.5
81.3
81.3 81.5 79.0 79.0 73.6 50.9
EL0
80.4 77.6
79.2
79.9 76.9
so. 2
63.0
77.2
78. S 77.2
82.3
iB. 9
w. 7
64. li
70.0 i7. I
71. 1
67.5
6.3
78.4
70. d
79.6
i9.1 7Y.S 78.4
80.8
Period of observation
Years,
-
18
4
14 45
3 1
3
1 1
1
......
1 1
1
I
1
1 1
14 4
1
3 I
3
1
8
1
4 mnh
2
-1 1
1
1
1
11110s.
1 1
11 12
1
3 mw.
4.6
4.8
5 8
6
ct
ginal has 21.4, apparently an error.
Date.
1863,1865-188
187Ws83, 18861887. 1894-1895 1903,1904:
1895,1897-189!
18Y2-1905.. ... 1857-1899,1901
1896-1998. .... 1896.. ........
1895-1897. ....
1891-1SP.. ... 1892.. ........ 1899.. ........
190%
...............
1876.. ........ 1856.. ........
1876.. ........
lSi6.. ........ lR76.. ........ 1876.. ........ 1876.. ........ 1989-1902.. ... 198P1887.. ...
1876.. ........
l8r31-1886.. ... 18!18.. ........
1898-1m .....
lY9MI,.. .... I~YLCl500.. ...
1SIIO-lRW~. ....
1893-94.. .....
Iril~s, 1900.. ...
1898-99.. ..... lS90. .........
IBUU.. ........
3900.. ........ inan.. ........
is89-m. .....
141% ......... 1902.. ........ 1868 1879.. ... l(iS!I-1900.. ...
1894.. ........ 19U?-3.. ......
1900-1904.. ...
i8~~9-ign4.. ...
186'2-1868.. ... 1881-1888.. ... .............. ..............
Author1t.y for temperature recorda.
Ychott; Challen r Re t a : Bristowe and Wrigbt. Handbook of %it. frond., 3d edit., Edinh. and London, 1890, p. 231; MZ, 1896, 1906.
MZ, 1896,1897, 1898
MZ 1893.
Md 1894. Observ. Meteor. Lab. Quim. Cent. Guat. 1893 (1900).
Internat. Bureau Amer. &pub., Handbook for
Analea Mus. Nac., I. No. 7, San Salvador, 1904.
Honduras, 1904, p. 13.
Do.
Do.
Do. Do. DO. Do. MZ, 1905, p. 87.
MZ, 1896, p. 197.
Anales Mus. Nac., San Salvador, I. No. 7, 1904.
Challenger Repta Rep Nicsr. Canal Comm., 1897-1899 (lS99); MWR,
Do., ah%Rep. IT. S. Isthni. Canal Comal., 1899-1901
Rep Niear. Cau. Cbmm., p. li (1899).
(Same as for tireytown.)
Chdlenger Repts.
Niederlein State of Nicaragua, Philadelphia Corn-
(Same as for Greytowu.)
Same M for Desealo.) f; ureau Anier. Ropub. Handbook for Niear. (Bull.
1899 212.
(l r n ), p. 343-4.
mercirl k&ums, INS, p. 1617.
di!8: ;?Isthtil. Canal CQIUIU.. 1899-1901, p. 343-4
(1914). Do. Do.
1690. Anales Inst. Fis. Geog. Nm. CoataRica, 11, p. 1535.
schott
. Fis. aeog. Costa Rica. 11. 1902.
..
Bol. Iust
Bol. Inst. Fia (ieog. Costa;-tica, I-III,1901-1W?;
lnales inat. PIS. Cieog. &i'&sta Rim, VII, p. %.
Bol. Inat. Fla Geog. Costa Rica, I I ,I I I ,l W 3 ~~
ChahLIger XeIJtE.
~
MWR 1901. MZ, I'W4.
MWR, 1904, p. 267-72.
Do.
Schott. NZ, 1895, p. 105-110.
Do. Do.
the Tablas de Alturas por 10s Dres. Felis y Lenk in Anales del
Ministerio de Fomento de la Republic8 Mexicana, Tom0 XI, p.
363456, Mexico, 1898, and in Boletin de la Sociedad de Geo-
grah y Estadisticta de la Republica Mesicana for 1894, p.
207 et seq.
Where no determinations of latitude have been found in
these authors, measurements of the approximate latitudes have
been made from the maps of the Secretaria de Estado y del
Despacho de Fomento (Comision Geografica de Guerra y Fo-
mento. Carta de la .Republica Mexicana, Escala 1 :lo0 000) in
many sheets,' the Carta General de la Republica Mexicana of
Manuel Fernandez Leal, 1899; the maps of the Bureau of ___ 'Many of these sheets have also furnished altitudes.
American Republics for Mexico (1900), Guatemala (1902), Nica-
ragua (1903), and Costa Rica (1903); those of the Century
Atlas, New York, 1906; those accompanying Doctor Sapper's
pagers above quoted, and Rand, McNally & Co.'s maps for
Mesic0 and Central America. All latitudes obtained in this way are marked with an mterisk (*).
A comparison of the preceding data shows that a given mean
annual temperature reaches farther north and to a greater
elevation on the Pacific than on the Atlantic slope of Mexico.
Thus, the highest point on the Atlantic slope attained by the
isotherm of 25O C. is Actopan, in Vera Cruz, 311 meters eleva-
tion, whence the isotherm descends to sea level south of
Tuxpan, 20' 59' N. On the Pacific side the same isotherm
APRIL, 1908. MON!hY WEA- REVIEW. 97
reaches 488 meters at Colima and, a t no great elevation, to north of Culiacan (24' 48' N.). The isotherm of 20' has its
greatest elevations on the Atlantic side at Mirador, Vera Cruz,
1,000 meters, and at about 700 meters in Nuevo Leon, while
on the Pacific side it reaches 1,560 meters at Oaxaca, and as
much in Sonora. (Compare Magdalena.) Deprest portions
of the central plateau have a higher mean annual temperature
than less elevated points in nearly the same latitude on the
Atlantic slope.
These remarks are suggested by the assertion by a recent
zoological writer (Gadow, Proceedings Zoological Society of
London, 1905, 11, p. 196) of the existence of a much cooler
climate on the Pacific side than on the Atlantic side of Mexico
at almost the same elevation.
Records of mean monthly temperatures for a considerable
number of other Mexican localities exist in literature (e. g.
MWR 1896-1906; BOM 1888,1889,1895-1902,1904; Anales,
Ministerio de Fomento Repub. Mex. I, p. 649 et seq., IX, p.
329 et seq.; Barcena and Perez, Estudios de Meteorologia
Comparada, Mexico, 1885, etc.), but these monthly records are
not sufficiently numerous or continuous to permit of calcula-
tions of the mean annual temperatures of their respective
stations.
(Compare Lerdo and Monterey.)
A SMAU CLOUDBURST NEaR SHASTA, CALIFORNIA.
The art& on 'cCloudbursts," by Mr. Edward L. Wells,
Section Director, Boise, Idaho, publiuhed in the Yearbook
for 1906, suggests that the ruggedness of the country has to
do with these .special phenomena, which certainly are not tornadoes or waterspouts, properly so-called. In this connec-
tion I would state that during the winter of 1890 I lived in
the town of Shasta, Gal., and put in much of the time pros-
pecting in the vicinity. On one of these trips I came upon
the opening of a steep and narrow, rocky ravine, down which
had recently poured a tremendous dood of water. Ascend-
ing this ravine, I noticed that the leaves and bushes on its
sides were .covered with mud and grass roots, showing
that the water must have had a depth of at least 30 feet as
it came down the gulch.
At the upper end of the ravine, or gulch aa it would be
called by the local miners, and just below the crest of the
ridge, I found a place approximately 50 feet square, where
all the soil and loose stones were completely washed away,
together with the bushes and one pine tree nearly two feet
in diameter, just as would have been done by turning a
huge stream of water upon it under heavy pressure. The
pine had been carried some distance down the gulch.
Standing upon the spot and carefully regarding all the
evidence in sight, I could form no other conclusion but that
here, within the past few days, had fallen a veritable river
from the clouds, leaving nothing where it fell except the
hard bed rock.
I saw many similar denuded spots in the vicinity, but
none of so recent a date as to leave any positive evidence of
the manner of denudation.
All of these denuded spots occurred within two miles of
the town of Shasta and on the eastern side of the low range
of hills surrounding it on the west, northwest, and south-
west.
By R. H. McCAnDLEss. Dated C'al~~ellq Cal., February 10, 1908.
LOUAL CHANGES OF CLIMATE.
I was much interested in the short editorial on
By W. C. ~EVEREAUX, Local Forecnster. Dated Milwaukee, Wis., Februnry 12, 1908.
Changes in
climate " which appeared in the Wisconsin Agriculturist, of
January 30, 1908. As this is a most interesting subject I have
carefully examined the records of this office with a view of
discovering what changes, if any, have occurred in the climate
of Wisconsin, and especially in this part of the State.
The statement is frequently made that the winters in this
vicinity are gradually becoming milder and that the snowfall
is decrdasing. Just about a year ago the temperature fell to
50' below zero at two places in the northern part of the State,
and this low reading has not been surpast by any known
record in Wisconsin. On the 28th of the following April there was a heavy snowfall over the northern part of the State, while
at Milwaukee on January 28 of the present year, 16.0 inches
of snow fell in twenty-four hours, which is the heaviest fall
that has occurred since the records began in 1885; and the
total fall for January, 1908, wau 29.0 inches, which is the third
largest fall on record for that month.
The precipitation record at Milwaukee for the past thirty-
seven years shows that over 60 inches fell in 1876, while there
were only 18 inches in 1901. This might lead one to hastily conclude that the rainfall is decreasing very rapidly, but there
appears to be no great cause for alarm, for the precipitation
since 1901 has varied only 1 per cent from the average for the
thirty-seven years.
The temperature record since 1870 shows no appreciable
change in the climate at this place, the mean temperature for
1907 being only 0.3' above the normal. The highest tempera- ture at this station was 100' on July 16, 1887, and again on
July 20, 1901, while the coldeut days were January 9, 1875,
with 25' below zero; January 5, 1884, with 24' below; Feb-
ruary 9,1899, with 22' below, and January 25, 190.1, with 23'
below. These extremes in temperature are well distributed thruout the period covered by the records.
In reference to the prevailing idea that the rainfall is in-
creasing in the arid country, I have carefully examined the
records of several hundred stations in the arid and semiarid
regions along the eastern slope of the Rocky Mountains, and
find that the precipitation for 1907 was not only decidedly
less than the average for the four preceding years, but was
about 10 per cent below the average for the last twenty or
thirty years. From this it would hardly be safe to infer that
the rainfall is decreasing in that region, neither is it correct
to. conclude that the rainfall is increasing after a few compara-
tively wet years.
As one of the newspapers in this city well said in a recent
issue-
The seasons are likely to succeed each other for a longer time in the
future than any one alive is likely to survive. There will be seed time and harvest. There will be blustering Marches and showery Aprils, and balmy Junes, and torrid Julys and Augusts. There will be pleasant autumns and bleak Decembers, and there will be winter cold as well as sunimer heat- just aa there was in the olden times * *. In those olden times, as now, there were open winters now and then, and cool summers now and then. The general run of weather in this latitude can be depended upon *. The open winter of the present year has been open enough to let in plenty of cold wind from the north and northwest to insure the SUCOBSS of the ice crop.
The United States Weather Bureau is interested in making
an authentic record of the climatic conditions of the country
and in distinguishing between an apparent change in the cli-
mate and the variability of the weather. If an appreciable
climatic change should be discovered, Prof. Willis L. Moore,
Chief of the Weather Bureau, would be prompt in publishing
the fact, but as he stated' before the Committee on Agriculture
of the House of Representatives, at Washington, D. C.:
It is my duty to publish the simple, ungarnished facta in regard to the ollmatic conditions of the United States. Our people want the truth
so that they may not be misled either by those who honestly, but never- theless ignorantly, claim that hot winds and droughts will never again come, or by those who, when periods of deflcient rainfall occur, as they have in the past and as they certainly will in the future, preach dis-
couragement and the abandoning ob lands which, on the average of a
long period of years, it would be profitable to cultivate.
.
But they were exceptional.
1 See Monthly Weather Beview January, 1907, Vol. XXSV, p. 13.