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During March 169 applicants were elected members of the Society, bringing the total up to 754. From merely a preliminary survey of the membership, 50 of these 754 have been elected fellows. Balloting for others is in progress. When the Council has agreed on a definite interpretation of the fellowship provisions in the Constitution, further elections will be made.

It is with regret that we announce the death on December 29, 1919, of Major E. W. Crockett, at Washington, D. C. Maj. Crockett was Chief of the Training Section of the Balloon and Airship Division of the Air Service. He was among the first to signify a desire to become a member of the American Meteorological Society. Death was due to apoplexy.


At a meeting of the Council held in Washington, D. C., March 23, 1920, a committee was appointed to determine the best ways to bring before business men the advantages which will accrue to them by having their companies or corporations become members of the Meteorological Society. The committee was started with three members:

Chairman, Robert E. Horton, Consulting Hydraulic Engineer, Voorheesville, N. Y.; Edward H. Bowie, Forecaster, Weather Bureau, Washington, D. C.; Charles F. Brooks, Weather Bureau, Washington, D. C.

The committee plans to increase its membership appreciably in the near future. Suggestions will be gladly received.



The following is taken from a letter received from Professor A. A. Knowlton, Department of Physics, Reed College, Portland, Oregon:

"I have just been looking over the reprint, 'Meteorology as a Subject for Study,' and find myself interested anew in the development of a course in the subject in my own department. I have previously done some of this in a rather elementary way but still from the standpoint of physics-a one semester course following a year of college physics. *** If there is a real opportunity in the Bureau for men, I should be glad to call this to the attention of my students as a possible vocation and to coöperate with the Bureau in the development of a course in this planned on real scientific and engineering lines. Do you think it worth while to undertake a thing of this sort? If the Bureau cannot coöperate in the matter what may one reasonably say to students as to the attractions of meteorology as a life work?"

The Committee on Meteorological Instruction would welcome any comments on these queries which many others have had in mind. After some discussion it may be possible to frame some definite recommendations.

LOCATION OF CORN BELT AS DEPENDENT ON INCLINATION OF EARTH'S AXIS. Dr. Humphreys' "eleventh paradox"-namely, that the south circumpolar region receives more heat during its mid-summer period than does an equal equatorial area, involves a principle that applies to corn growing. Corn is a more prolific crop in the zone which includes Kansas and Nebraska, than in tropical regions. A reason therefor is not hard to find. The following illustration-empiric, let us grant-will make the matter plain. Let us assume that in

equatorial regions a given surface receives an average of 100 heat units per hour; in a 12-hour day it receives a total of 1200 heat units. Now, at the 40th parallel, because of the obliquity of the sun's rays, an equal area receives approximately an average of 93 heat units an hour; but the period of sunshine in midsummer is nearly 15 hours; that is, the same area receives nearly 1400 heat units per day -anyway, a considerably greater insolation than is received within the tropics. Corn is a plant requiring a steady warmth and much of it. The warm days of the 40th parallel are followed by warm nights. Within the tropics the days are not warmer, and the nights are colder than in Kansas, during midsummerand the corn plant responds to this condition. To generalize a proposition: The angle of inclination of the earth's axis determines the location of the corn belt. So far as latitude is concerned the United States is more favorably situated for corn growing than is Europe, and the United States is the world's greatest corn field.-Jacques W. Redway.


IS IT WORTH WHILE TO HUNT FOR PERIODICITIES IN THE WEATHER? The ceaseless change of meteorological conditions from day to day, month to month, and even year to year, presents a complex sequence of phenomena that, as an ignis fatuus, has lured many earnest students to search for definite periodicities. A whole library would probably comprise the mass of literature and contributions to this question. Students prompted to pursue any studies of this character must not, however, fail to qualify themselves properly and guard against pitfalls by carefully studying sound contributions to the analysis of periodicities by means of the Fourier series, periodograms, and like agencies of analysis. A few of these are cited below.

"On the Harmonic Analysis of Sun-spot Relative Numbers," by Hisashi Kimura; also

"On the Harmonic Analysis of Wolf's Sun-spot Numbers, with special reference to Mr. Kimura's paper," by H. H. Turner. Both in Monthly Notices, Royal Astronomical Society, 1912-13; and

"A Periodogram Analysis of the Greenwich Temperature Records," by Capt. D. Brunt. In the Quarterly Journal of the Royal Meteorological Society, October,


The conclusions reached by Brunt with reference to the examinations of the Greenwich temperatures might well be made applicable in a general way concerning periodicities in other meteorological elements:

"One is forced to the conclusion that, except for the annual variation and its submultiples, periods in the astronomical sense do not exist in these temperature records. Some of the periodicities which we find in the Greenwich mean temperatures appear suddenly, hold the field for a time, and die away with equal suddenness. It will probably require an investigation of records extending over several centuries to determine any law in the recurrence of the periodicities. The interval of 65 years treated above is far too short to determine this. In the present state of our knowledge their recurrence appears so arbitrary that even the periodicities derived above can scarcely lead to results of value in forecasting monthly mean temperatures."

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"The investigation of the continuity of the different periods considered above points to the conclusion that there exists no stable periodicity except the annual


If this conclusion is justified, it is clear that the periodogram analysis is not in itself sufficient to deal with temperature variations." C. F. Marvin.


Raingage exposures.-Although the Weather Bureau provides for the inspection of each coöperative station at least once in three years, and although the coöperative observers earnestly desire to have their records accurate, it is difficult in many instances to keep the raingage in a place where it is pretty sure to be free from the effects of surrounding buildings or trees and with its rim in a horizontal position. Therefore, the Committee on Hydrological Meteorology suggests that anyone noticing a raingage poorly placed or on a slant, talk with the observer, in order to improve the exposure. Since the Section Director of the Weather Bureau should know about any rainfall records which may be inaccurate because of misplaced gages he should be informed of the condition found, how long it may have existed, and whether or not the observer corrected the trouble. This suggestion is made wholly in the interest of having our rainfall records as accurate as possible; and is in no wise to be interpreted as a spying system on observers nor as in any way an interference in the close relations between the Section Director and the coöperative observer.


The Weather Bureau has numberless unsolicited testimonials as to the value of its forecasts and warnings and also a great number of letters giving instances of losses, occasioned by injurious conditions, that might have been prevented by taking advantage of the warnings. Only the winter before last, for instance, a cattleman in Texas lost about 1000 head during a severe cold wave and was quite sore at the Bureau for not having warned him if its approach, when the fact was that the Bureau had issued ample advance warnings of the cold wave, and the calamity might have been avoided had he put himself in touch with the Bureau beforehand through the nearest Weather Bureau station and taken heed of the warnings.


If you are engaged in any business or occupation in which the weather is any considerable factor, and especially if you are in charge of any important interests, such as stock, truck or fruit raising on a commercial scale, or the shipment of perishable produce that is liable to be affected by severe and injurious weather conditions, such as cold waves, floods, frosts or freezing weather, or heavy rain or snowfall, you are not an efficient manager if you have not put yourself in touch with the U. S. Weather Bureau and arranged to receive advance warnings of these conditions. Property running into the millions in value is saved annually by attention to these warnings, and unfortunately other millions are lost through failure, either from carelessness or ignorance to take advantage of them. Arrangements to receive the warnings, which are issued from 24 to 48 hours in advance, may be made with the nearest Weather Bureau office, or by addressing the Chief of the Weather Bureau, Washington, D. C.

Editors of agricultural and trade papers: Would not the insertion of the paragraph above in autumn and once or twice during the winter be of value to some of your readers?-H. E. Williams.

THE WORK OF A WEATHER BUREAU OFFICE IN A LARGE CITY. The local office of the Weather Bureau in a large city is the center of a great amount of work of considerable diversity. Here is an informal catalog of the daily service rendered by the force of 12 men at New York City:

4000 forecast cards to print and mail; occasional display of storm warnings. 3000 weather maps to print, wrap and mail.

Make 6 large-scale weather maps on glass, for exchanges, etc.

Answer some 1500 telephone calls.

Take care of probably 50 to 100 callers after meteorological or climatological data embracing the whole earth and air and water.

Coöperate with the Army Air Station at Mitchell Field, Long Island.

Consultation and advice to big concerns who wish to put in meteorological equipment for their own problems.

Answer on an avearge of about two calls to court to testify as to weather conditions at certain times and places, and sometimes to give astronomical information.

At least a dozen newspaper interviews.

Informal talks or lectures to classes from schools, colleges and institutions almost daily (e. g., a class of 50 men and women who are in training for inspectors in the Board of Health).

Maintenance (and occasional change) of two fully-equipped sub-stations, in addition to the observations at the central station.

Records to adjust for an area that equals about six counties, with constant attention to harmonize the records of the three fully-equipped stations.

Compilation and publication of weekly and monthly reports of the Central Park Observatory for the Board of Health and City Record.

THE MONTHLY WEATHER REVIEW, JANUARY, 1920 (ISSUED APRIL 5). The Monthly Weather Bureau begins its 48th year in good style, though somewhat restricted in size and edition because of the Weather Bureau's shortage of printing funds. There are eight contributions and 30 abstracts and notes (dealing mostly with winds, and cooling of the lower air). As perhaps half the membership of the Society receives the Monthly Weather Review, or has direct access to it, and since the Review goes to some 500 public, society, and college libraries in the Western Hemisphere, there will be no attempt in this Bulletin to do more than present abstracts of the original contributions.

Average free-air conditions as observed by means of kites at Drexel Aerological station, Nebraska, during the period November, 1915, to December, 1918, inclusive. W. R. Gregg. 8 figs., pp. 1-II. (Reprints being made.) [Author's note:

Tables and figures show average monthly, seasonal and annual values of air pressure, temperature, humidity and density; average seasonal and annual wind conditions; and the relations between winds in the free air and at the surface. Values are given for various levels up to 5 kilometers. The data are compared with similar results obtained at other places, particularly at Mount Weather, Va., which is in nearly the same latitude; and one of the tables contains summer, winter and annual values of density from sea level to 10 kilometers, as determined by different investigators for various parts of the world. At and near the surface there is, of course, an increase with latitude; at 9 kilometers, however, there is close agreement at all places from the equatorial regions to the highest latitudes at which upper air soundings have been made.

One of the figures of special interest is that showing the turning of winds with altitude. Briefly, the average relations of free-air to surface winds are: (1) Surface easterly to southwesterly winds veer with altitude; (2) west-southwesterly to west-northwesterly winds remain practically constant; (3) northwesterly to north-northeasterly winds back slightly; and (4) northeasterly and east-northeasterly winds change but little up to 2 kilometers, above which level they back and veer, respectively. The figure shows further that the veering or backing of these winds is such that a west component prevails at 3000 meters for

all surface winds; that the convergence continues until at 4000 meters winds are nearly always between northwest and southwest; and that the north or south component in the surface winds still persists at the highest levels explored.

Similar summaries are contemplated for other aerological stations, as soon as sufficient data are available. It will then be possible to furnish charts showing average conditions at various altitudes over different parts of the country east of the Rocky Mountains. Such charts, and studies based thereon, will be of inestimable value in aviation, ballistics and forecasting. Their value would be immeasureably increased by the establishment of additional aerological stations, and it is to be hoped that funds for this purpose will soon be made available. ] Sunshine in the United States. J. B. Kincer. 9 figs., pp. 12-17.

[AUTHOR'S SYNOPSIS.-Sunshine is a very important climatic element, not only from the standpoint of the agriculturist, but also from its physical effect on man and other animals. The depressing influence on human beings of long periods of cloudy and damp weather is noticeable even to the casual observer, while, on the other hand, long periods of successive days with continuous sunshine and high temperature are trying on all animal and plant life. Long, hot periods are usually characterized by few clouds and much sunshine, when, day after day, the amount of insolation received during the daytime results in an accumulation of heat in excess of that lost at night by radiation. Finally a change in pressure conditions results in the breaking up of the stagnant atmosphere, bringing refreshing winds and welcome clouds to relieve the situation.

Sunshine data are recorded and expressed either in values giving the actual amount in hours and tenths, or by indicating the percentage of the possible amount. Each of these methods has advantages not possessed by the other. Owing to the large seasonal variations in the possible amount, the actual duration of sunshine from month to month is not disclosed directly by a statement of the percentage of the possible. For in such a case, a knowledge of the latter is necessary before the actual amount can be determined. For example, along the north-central border of the United States, a day with four hours of sunshine the latter part of December would have 50 per cent. of the possible, while a like amount the latter part of June would be only 25 per cent. of the possible. On the other hand, the percentage of the possible amount gives a better direct indication of the seasonal variations in cloudiness than does data showing the actual number of sunshine hours. Published sunshine data for the United States are given mostly in values showing the percentage of the possible amount.

In view of the advantages possessed by each of these methods of presenting data, they are given in this study in both values and in considerable detail. Charts and graphs are presented showing the mean solar time of sunrise and sunset, and the average length of the day, sunrise to sunset, representing the possible maximum amount of sunshine for different seasons of the year. Included is a series of charts showing for each month the average amount of sunshine in hours per day; also charts and graphs showing the seasonal and annual distribution in percentages of the possible amount. Other charts show the percentage of days clear, partly cloudy, and cloudy, while the diurnal distribution of sunshine is also graphically shown. There is included a table showing for each month and for the year the average percentage of the possible amount of sunshine for all stations where continuous automatic records are made, which include practically all regular reporting stations. The basic data are for the 20-year period from 1895 to 1914, except that the percentages of the possible amount are for the 8-year period from 1905 to 1912.]

(Those wanting reprints of this article should apply to "Chief, U. S. Weather Bureau, Washington, D. C.")

On observations of solar and sky radiations and their importance to climatology and biology and also to geophysics and astronomy. C. Dorno. pp. 18-24. This paper is a good summary of the status of the subject stated in the title. We have come to the point where radiation as a climatic factor is recognized as highly important, and we are witnessing an increasing dependence on actual measurements of radiation instead of on guesses. No climatic element varies so greatly from place to place or from season to season as does radiation. And when we speak of "radiation" this means a complex which must be measured in calorific, luminous, chemical and bactericidal, terms, if we are to know its makeup:

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