Imágenes de páginas

"The solar radiation is by no means always similarly composed; the low sun is much richer in long-wave radiations (much redder) than the high sun, as every one knows from experience. Also with the same elevation of the sun there exists a pronounced yearly march. The spring sunlight is—at least on the Alpine heights-much richer in heat rays, that of autumn much richer in the ultraviolet ones. The difference between sunlight and shadow light increases in marked degree with elevation of the sun and still more so with the color of the light, since the sky as appearance teaches, is much richer in short-wave (blue) light than the sun with its long-wave rays (infra-red, red, and yellow). With middle sun elevations and cloudless sky the red light of the sun falling on the horizontal surface is found to be 14 times stronger than that from the sky, while its brightness is only 11 times stronger, its chemical rays only 4.4 times, its pure ultra-violet (bactericidal) rays even less strong than (only about half so powerful) those of the sky."

C. F. B.

Smoke formations in air drainage. C. Hollenbeck; with an introduction by J. Warren Smith. Fig. p. 21-25.

[In the Roswell, N. Mex., fruit district, during cold nights, the tops of fruit trees may be frozen, but not the bottoms. This happens when air cooled over the dry, open plains during a clear night, slides in a thin sheet out over the air in the valley. The movement of smoke early in the morning, Dec. 9, 1919, showed this process in operation.]

A cloud cross-section of a winter cyclone. C. F. Brooks. 2 figs., pp. 26-28. [Excerpted from the paper, Clouds and their significance, presented at the first meeting of the Society-mentioned in the Bulletin, Jan., p. 9.]

Snow crystals from the crystallographic standpoint. E. T. Wherry. 32 figs.

Pp. 29-31.

[AUTHOR'S SYNOPSIS.-The magnificent photographs of snow crystals taken by Mr. W. A. Bentley and recently published by Prof. J. C. Shedd, a few of which are reproduced here (together with some additional ones recently submitted by Mr. Bentley to the writer) bring out interesting and important facts not only in the domains of meteorology and physics, but also in that of crystallography. They confirm the view that ice is ditrigonal-pyramidal in crystallization, and yield considerable information as to the course of the crystallization process under different external conditions.]

Would a large reservoir increase rainfall? A. J. Henry. pp. 31-32. [The reply of the Weather Bureau to the inquiry of a tropical Government is outlined, indicating that since lack of rainfall is due to lack of cooling processes rather than to lack of moisture in the air, and since reservoirs elsewhere do not seem to have affected local rainfall, the outcome of engineering projects designed to increase rainfall is likely to be disappointing.]

How rainfall data may be used for determining road conditions. T. G. Ship

man. p. 33.

[When a report of road condition is not to be had, but the recent rainfall amounts are known, some idea of road condition may be had, if from previous comparisons of rainfall with road conditions the factors are known. Arkansas roads are cited.]


The Senate, on March 24, passed the Weather Bureau increased appropriations as mentioned in the February Bulletin.

A year ago, the Signal Corps meteorologists at Camp Knox were singing: "O, we won our fights

"With theodolites;

"We broke the Kaiser's wide rule

"With every sort

"Of weather report

"Sing ho! the shining slide-rule!" (Received from) R. A. Simon.

When the Hotel Chamberlain burned at Old Point Comfort, Va., on March 7, 1920, a cloud formed over the smoke column. The wind blew in toward the fire from all sides. (Several articles on clouds over fires have been published in the Monthly Weather Review, March, 1919; some reprints are still on hand at the Weather Bureau, Washington, D. C.)-I. R. Tannehill.

The council of the Scottish Meteorological Society proposes to hold a series of meetings, mainly in Edinburgh, at which lectures on popular lines will be given or discussions opened on questions of meterological interest. The first of these lectures, has, indeed, already been given in Glasgow by Capt. Franklin, who opened the winter session of the Royal Philosophical Society of Glasgow by an address on "The Study of Meteorology in Schools and Universities."-Nature (London), Jan. 1, 1920, p. 444.


Descriptions of the auroras of March 22–25, 1920, wanted.—The Weather Bureau is collecting descriptions of the magnificent aurora which was observed practically throughout the eastern half of the United States on the night of March 22-23, 1920. The latitude of greatest brilliance seems to have been 41° or 42o, and as far south as Augusta, Ga., the streamers reached to about 45° above the northern horizon. The time of greatest brilliance was from 10 to 10.05 p.m., 75th meridian time. As in the case of previous great auroras, e. g., March 7-8, 1918 (Monthly Weather Review, June, 1919), the Weather Bureau hopes to publish a compilation of the descriptions of this display. At Washington, a faint aurora was seen on the evening of March 23, and a peculiar spot-light display was observed practically throughout the following night. Descriptions of these auroras as seen elsewhere will also be welcome.-C. F. Brooks.

Designs for a seal for the Society solicited. The Council at its meeting on March 23 tentatively approved Prof. Talman's suggestion of "Am. Met'l Soc." for the official abbreviation of the Society's name, but decided to ask for suggestions from members of the Society, and also to ask for designs for a seal, without, however, obligating itself to adopting one.

Price of the Bulletin to non-members, including libraries, colleges and educational institutions, is $1 per year.


In the February Bulletin, p. 27, the high-speed pilot balloon flight observed from Lansing, Mich. was said to have been at a Signal Corps station, whereas the aerological station there is in charge of the Weather Bureau.

Application pending for entry as second-class matter at the Post Office at Easton, Pa.




Vol. 1

Published Monthly by the American Meteorological Society
Publication office: 207 Church Street, Easton, Pa.

APRIL, 1920


No. 4

As this issue of the BULLETIN goes to the printer, the Washington meeting of the Society is in progress with well-attended sessions. A detailed report of it will be given in the May issue of the BULLETIN.

A. A. A. S. MEETING IN SEATTLE, WASHINGTON, JUNE 17-19, 1920. The Pacific Division of the American Association for the Advancement of Science will hold its usual annual meeting at the University of Washington, Seattle, June 17-19, 1920. Members of the American Meteorological Society who expect to attend should communicate with Prof. E. J. Saunders, Dept. of Geology, University of Washington, Seattle, in order to have at least an informal meeting to get acquainted and perhaps to discuss the possibility of forming a Pacific Section of the American Meteorological Society. Any meteorological papers which the members of the Society may wish to present should on this occasion be given at the sessions of the Physics Section or Geology and Geography Section of the A. A. A. S., as there is not sufficient organization of the Society in the Pacific region to justify a separate program for this meeting.



Professional meteorologists are frequently consulted by prospective purchasers of meteorological instruments. Officials in charge of section centers of the Weather Bureau receive many requests for advice concerning instruments, and their recommendations carry considerable weight. Instrument dealers recognize this fact, and cordially coöperate with such officials.

The point to be made here is the fact that such recommendations should invariably urge upon the prospective purchasers the desirability of securing standard equipment. This is especially true of thermometers, thermometer shelters, rain gages, and apparatus for measuring evaporation. Those about to purchase equipment of their own should be told that in order that the data obtained may be comparable with similar data secured at 5000 or more Weather Bureau stations in the United States, it is extremely desirable that standard equipment be purchased, and the same installed under standard conditions of exposure.

The importance of this fact may be illustrated by a statement of conditions the writer has encountered in California. Many years ago the Southern Pacific Railroad supplied every station agent in California with a common mercury thermometer and a rain gage which was 3 inches in diameter and 12 inches long. The thermometer was nailed to the railroad station, with no enclosing shelter of

any kind, and occasionally in a place where the sun shone upon it during a portion of the day. Though the railroad agents have many and varied duties, they were required in addition to take readings of the thermometer at three specified times during the day, and to measure the water which accumulated from time to time in the rain gage. For many years worthless meteorological data have been accumulating in the headquarters of the Southern Pacific Company in San Francisco. The rain gage used is faulty in that it registers a deficient catch during precipitation, and, moreover, in the mountain regions, where 25 to 30 feet of snow sometimes accumulates on the ground, the small gage is of little more value than a toy.

Nothing smaller than an 8-inch standard rain gage should be recommended to prospective purchasers of a gage. Standard thermometers, though they cost more than ordinary thermometers, are the only kind worth purchasing. The coöperation of the instrument maker and the retail dealer will aid materially in securing the installation of standard equipment.-A. H. Palmer.


Sun kinks in barograms and thermograms are not so rare as to be a subject of especial comment. The record of a thermograph in a shelter not very fortunately situated on account of the reflection of sunlight at times during the winter months, shows a sun kink (2° F. upward hump) at 9.00 A.M. each day, due to the reflection of strong sunlight, on Monday (Mar. 8, 1920), Tuesday and Wednesday. On Thursday the sky was overcast with high clouds, but the sunshine recorder was registering at the time. On Friday and Saturday there was no sunshine registration, but the sun kink is noticeable on all three days. On Sunday there was strong sunshine, but the fact that a considerable snow had blown into the shelter, half burying the thermograph, may possibly account for the feeble sun kink.

The fact to be emphasized is the persistence of solar radiation through a thick cloud blanket. The occasional exposure of a black-bulb thermometer has shown that high temperatures may occur when the sky is overcast and the temperature of the air is below the freezing-point.-J. W. Redway (Meteorological Laboratory, Mount Vernon, N. Y.).


In the advertising portions of several well-known magazines there appear each month calls for agents to sell advertising thermometers. The latter consist of glass thermometers, four to ten feet long, mounted in a groove of a board on which space is available for advertisements. The agent goes to a small town, sells the spaces to local merchants, paints the advertisements in the alloted spaces, nails up the thermometer in some conspicuous place, and passes to the next town, perhaps never to return. It is needless to add that these thermometers are often badly exposed, they are usually unreliable, and they receive little attention after once being installed.

The unfortunate fact in connection with this matter is the confidence which the public places in the temperatures indicated by these thermometers. With few exceptions, the instruments are found displayed in small towns only. The temperature data are sometimes published in the local newspapers. In traveling about California the writer has discovered a number of these thermometers in public places. Several were found so exposed that the sun shone directly upon them during a large portion of each clear day. In one case it was found that the

glass thermometer tube had slipped along the groove in the wood, making the indicated readings inaccurate, as the scale marks were painted upon the wooden background. Most surprising of all was the caption "Weather Bureau" found on several of these instruments. It was subsequently learned that legally the use of this caption cannot be denied so long as the "U. S." was not used also. Needless to say, the U. S. Weather Bureau is not connected in any way with the display of these instruments.

It is unfortunate that such defective and badly exposed thermometers are tolerated by the local authorities. Such abuse of public confidence is to be deplored. Most newspaper editors recognize the faulty character of such temperature data when the matter is presented to them in a sympathetic spirit. Here is a field of education in which the American Meteorological Society may render valuable service.-A. H. Palmer.


Saranac Lake, New York, Winter 1919-20.

In the comparison of 197 outdoor household thermometers with a sling thermometer at temperatures ranging from o to -30 degrees Fahrenheit, it was found that there was a mean error of 3.2 degrees Fahrenheit as compared with the sling thermometer. Of this number 120 gave a reading too high, and 68 a reading too low, while 9 were correct at the observed temperature. The greatest error found was 30 degrees.-H. I. Baldwin.

Weather by the Rule of Thumb.

From the Philadelphia Ledger.

That the mass of people refuse to believe that meteorology is an exact science is shown in that the long-range prophets of the weather to come during the next four months are now busily at their predictions. This indifference to a science which is quite as orderly, so far as a grasp on causation goes, as astronomy, is one of the mysteries of modern education. For it is more than a generation ago that all the school books that deal with physical geography set out the real facts about weather phenomena. And yet, while every one accepts as final all statements as to astronomical facts, weather lore is ignored and a ready recourse is had to any gray-bearded loon who pretends to read the signs of the times. Moreover, few seem to see the grotesque absurdity in the fact that the long-range forecasters who live within a few miles of each other predict absolutely opposite kinds of weather for the days to come. Old Bill Billkins, the squirrel hunter, tells you that the squirrels haven't stored up any nuts, and that the winter is, therefore, to be "open" and "without snow,' "while his neighbor, Squire Blower, assures the same gaping public that the buttonwood bark is thicker than ever before, because the trees anticipate a severe winter, while the pelt on the small game is heavier, in view of the zero temperatures that impend.

So it goes on with all sorts of addlepated conjecture tying up certain admitted incidents to effects with which they have nothing whatever to do. Yet the gullibility of the public is such that "prophets" who contradict each other flatly seem to be able to keep a local reputation and a name without any trouble, and even make money at the game. Of course, the real fact is that the condition of vegetation or of animal life in the autumn only reflects past influences and tells in some measure what the seasonal conditions have been through which the plant life and the animal life have just passed. But neither twig nor tree, neither goose, nor gopher, has any insight into the future, nor can any one of them anticipate the weather to come. If leaves be luxuriant and linger long on the trees, if the bark be thick, if the animals be fat and the fur sleek and glossy and abundant, all these things relate wholly and unqualifiedly to the weather experienced in the winter, spring and summer preceding the present state of the objects whose condition is utilized by the would-be forecasters.

« AnteriorContinuar »