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in August, 57 per cent. This distribution made ideal conditions for the cultivation of the crops. Then again, the dry weather in the early part of the season caused the corn to make extensive root-growth, so that the later rains produced large stalks and ears, which were permitted to mature under highly favorable weather conditions in September. The thermal constant was also generally favorable throughout the growing season and because of two abnormally warm months, February and March, immediately preceding seeding time, the soil was in a most excellent condition at planting time, and although the weather was persistently cool during the blossoming time this lack of heat was fully compensated for by an abnormal amount of sunshine. This abundant sunshine during the preceding fall, winter and spring was of incalculable value both to soil and plant in the quiet, secret processes of transforming plant food gathered from the soil and air first into plant tissue and later into seed or fruit.

We conclude, therefore, that the bumper crops in Ohio in 1925 were the result of an unusually fortuitous combination and distribution of the major climatic elements, such as rainfall, temperature, sunshine, winds, etc., to excellent cultivation and to the complete absence of all climatic misfortunes.

Discussion-Mr. Reed mentioned a similar year, 1895, in Iowa, that was dry, but produced bumper crops, and stated that correlation between rainfall and corn yield in Iowa was difficult. Prof. C. J. Posey remarked that many complex elements entered into corn yield and conditions favorable at one stage of the crop might be unfavorable at another stage. Mr. Reed stated one of the greatest handicaps in correlating weather and crop growth was lack of phenological observations.

The discussion that followed brought from Prof. Marvin the statement that, while phenological observations were valuable, the Weather Bureau was not considered the proper bureau to gather them, and some other bureau should take over this work. "Science must be divided somehow between the various Government bureaus."

As this concluded the forenoon's program, Dr. Milham announced the meeting would adjourn until 2 P. M., stating no arrangements had been provided for lunch in the building. Upon the suggestion of Mr. P. Connor, tellers were appointed to canvass the mailed ballot for officers for the ensuing year, Dr. Milham naming A. M. Hamrick and G. W. Pitman, to act as tellers, to report at the business meeting the following morning. Dr. Milham also announced the meeting of the Council immediately following the afternoon session, asking that the two temporary secre. taries attend.

SPRING MEETING OF THE SOCIETY

The Society will meet in Washington, at the central office of the Weather Bureau, 24th and M Streets, N.W., on Friday, April 30, and Saturday, May 1. The Friday session will be held in the evening, beginning at 7.30, for the presentation of papers requiring lantern illustration. The Saturday sessions will be: 9.30-12.30, and 2.00-5.00.

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Members who have attended the past Washington meetings will recall the very excellent papers and discussions, and especially the symposium last year, the success of which led to the adoption of a resolution favoring the holding of others. Let us keep the example of that last meeting before us in preparing for this one-an example not only to be followed, but to be improved upon. To allow the maximum co-ordination of papers and the best content, those who may be able to attend should begin now to plan, and should send to the Secretary or to Dr. Varney at least a tentative statement concerning any subject or subjects they may wish to present, or to have discussed. Several interesting papers are already in contemplation, on such diverse subjects as The Climate of the Earth's Cold Pole; The Shippers' Forecast Service of the Weather Bureau; Gulf Stream Temperatures and Eastern American Weather, January to March, 1924; A New Chart of Equal Annua Ranges of Temperature for the United States; The Climates of the Virginias.

The various scientific meetings held in Washington toward the close of April should prove an additional incentive to the attendance of our members. Several of the meetings will be of direct meteorological interest, others of collateral interest to all who would keep in touch with scientific progress outside their own specialty.

The meetings of the American Geophysical Union should perhaps be especially mentioned. They will be held, with one exception as noted, in the building of the National Academy of Science, 21st and B Streets, N.W., as follows: Thursday, April 29, Section of Geodesy, 9.30 A. M.; Section of Volcanology and Oceanography, 2.30 P. M. The Section of Terrestrial Magnetism will meet at the Carnegie Institution Building, 16th and P. Streets, N.W., 8 P. M. Friday, April 30, Section of Meteorology and Seismology, 9.30 A. M.; General Meeting of the Union, 2.30 P. M.

STRONGEST WIND ON RECORD IN THE UNITED STATES In response to a request for more information concerning the records of extremely high wind velocities on Mt. Washington, (See BULLETIN, Dec., 1925, p. 184), Mr. S. P. Fergusson has kindly supplied the following note:

I am indebted to Dr. P. C. Day, Chief of the Climatological Division of the Weather Bureau, for the following data of very high winds on Mount Washington:

1876, December, 180 miles an hour
1878, January, 186 miles an hour
1879, April, 182 miles an hour
1883, January, 180 miles an hour

Dr. Day states that the maximum velocity of 186 miles an hour was not recorded, but was read from the dial of an anemometer held by hand out of a window. It appears probable that the instrument was too near the building to be well exposed, consequently indicated less than the true velocity; also, there is some uncertainty in computing when the period of exposure is short. Recent studies of this anemometer show that the velocities quoted are about 25 per cent too high; but since brief gusts may vary 50 per cent above or below the average during a period of several minutes, it is possible that, after correcting these data, the maxima during periods exceeding one second may have exceeded 190 or 200 miles an hour.

The circumstances of the gale of the 10th and 11th of January, 1878, may be of interest: Between the 1st and 4th and the 5th and 11th, there occurred two examples of the merging, near the North Atlantic Coast, of northern and southern cyclones of unusual length of life and energy, followed by high temperature, excessive precipitation (mostly rain) and severe gales. In both, the energy of the single cyclone was greater than that of the two it replaced, and the second example was conspicuous for the unusual intensity of the cyclones before their union and for the rapid increase of energy afterward. The cyclones of the second example, respectively, appeared first over the Pacific coast near Vancouver and over Mexico, south of Brownsville, Texas, on the 5th. Both developed slowly and were nearly stationary until 7.35 A. М. on the 8th, after which time they moved rapidly eastward and northeastward, increasing in intensity. At 4.35 P. M. on the 10th, the northern cyclone, which had increased in area, was central over Lake Huron, having moved southeastward from near Winnipeg, while the southern cyclone had reached the coast of New Jersey. The minimum pressures, respectively, at this time were 29.73 and 29.34 inches. At 11 P. M. the two cyclones had joined on the coast near Nantucket, and the pressure had fallen to 29.07. At 7.35 A. M. on the 11th the new cyclone was off the coast south of Portland where the pressure had fallen to 28.90; after this time it decreased in intensity and its direction, which had been from the southwest, changed to west. The following notes of the observer on Mount Washington during this storm are copied from the Monthly Weather Review of January,

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The station was on a spur about 100 metres south of and 5 metres lower than the highest point about which the hotel and other buildings were grouped and which obstructed the wind when the direction was between N.N.W. and N.E. The exposure was good in other directions, hence, except for the uncertainties referred to, the velocities quoted may be accepted as approximately correct. But the wind on mountains appears to be invariably higher, sometimes 50 per cent higher than at the same level in the free air, as shown by the following comparisons obtained by me in 1905 and 1907. The stationary anemometer was well exposed on the highest building on the summit and the velocities in the free air were recorded by a Robinson anemometer carried by a kite flown 18 kilometres west of Mount Washington:

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The gale of July 27, 1907, was remarkable for the time of year, the velocity sometimes reaching 50 m/s (112 miles an hour) or 140 miles an hour on the incorrect scale in general use. The light kites used were driven down at a height of 1200 metres, and the free-air velocity of 26 m/s was extrapolated through the upper 300 metres of height, but is be lieved to be correct within 1 m/s.

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RADIO RIVER FORECASTS DAILY

(From The Official Record, U. S. Dept., of Agriculture, Jan. 6, 1926) The success of radio reception and distribution of weather reports and forecasts and of storm, cold wave, and other warnings throughout the entire country has been so marked and its value so evident that steps were recently taken by the Weather Bureau to extend the radio service to cover the dissemination of daily river stage data, river forecasts, and flood warnings.

Cincinnati, Ohio, by virtue of its pre-eminently strategic position for river purposes, was selected as the starting point. The operation of the great system of locks and dams on the Ohio River for the benefit of navigation is under the control of the United States Army Engineer office at Cincinnati and the cordial and effective co-operation of the Corps of Engineers forms an essential feature of the river radio work. The engineers furnish daily to the Weather Bureau a large volume of river data and likewise assist very greatly in the dissemination of available river information, all without cost to the Weather Bureau.

On December 2, 1925, the Weather Bureau office at Cincinnati began the daily broadcasting at 10.40 A. M., central time, through the Crosley Radio Corporation (WLW), of the new river bulletin. This bulletin contains the morning stages of the Ohio River at 20 or more stations, the condition of the river, whether rising or falling, the position of the movable dams, whether up or down, the 24-hour precipitation at all sta tions, the river forecasts for the Ohio River and its principal tributaries, and a general weather forecast.

The success of the new service was immediate and a great many letters of commendation and appreciation were received. The service is, of course, free to all, and is given daily, including Sundays and holidays. As it was well expressed by Maj. A. K. B. Lyman, Corps of Engineers, Cincinnati, "If you do not feel like going to the office Sunday morning the message will be handed to you at the breakfast table."

Similar service of a more limited character has been furnished for some time past at Pittsburg, Pa., St. Louis, Mo., and Davenport, Iowa, and the success thus far attained has encouraged officials interested to take steps for its further expansion, as well as for its extension to other important river centers. There can be no doubt that both will be successfully accomplished.

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NOTES ON PUBLICATIONS
Thermodynamics for the Meteorologist

By EDGAR W. WOOLARD

Meteorology, in the strict sense of the term, is, as has often been emphasized1, the study of the dynamics and the thermodynamics of the earth's atmosphere. The earlier investigations in theoretical meteorology were concerned almost entirely with the dynamical aspect of the problems involved; but the study of the energy of winds and storms was initiated early in the twentieth century by Margules, and in recent years the thermodynamics of atmospheric phenomena has been receiving more and more attention. In order to follow the important investigations in physical meteorology now being reported in the journals and incorporated in modern meteorological treatises, and to be able himself to contribute to the solution of current fundamental problems, the meteorologist must include in his equipment a knowledge of the principles of thermodynamics.

1 Cf. Woolard, BULL. AMER, MET'L. Soc., 6, 78-81 (1925); Hann-Süring, Lehrbuch, 4te aufl., pp. 1-2.

An obstacle to this accomplishment has hitherto been the remarkable dearth of text books suited to this particular purpose. There are many appropriate treatises on the general subject of Heat; but neither the existing works on engineering and chemical thermodynamics, nor the standard expositions of abstract thermodynamics meet the needs of one whose major interests lie elsewhere and who desires a brief and simple exposition of the essentials from which he may easily and quickly acquire a practical working knowledge of the fundamental laws and principles.5 It is therefore of especial and timely interest to meteorologists that there has appeared an interesting and exceptionally lucid exposition of the difficult subject of thermodynamics, written expressly to set out the fundamental principles and their applications to other sciences for the use of those whose major interest may lie in any one of the latter, and which fulfills this purpose admirably. We refer to G. Birtwistle's Principles of Thermodynamics (Cambridge Press, 1925), a small, inexpensive, and refreshing volume, which will equip the reader either to follow the literature of his own special subject at once, or to pursue further such special thermodynamical topics as he may find necessary.6

2 E.g., Sir Napier Shaw and H. Fahmy, Energy of saturated air in a natural environment, Quar. Jour. Roy. Met'l Soc., 51, 205-228, 1925 (and the other references cited therein); G. C. Simpson, The new ideas in meteorology, Nature, 116, 361-365, 1925; D. Brunt, An outstanding problem of meteorology, Met'l Mag., 60, 253-256, 1925; L. F. Richardson, Supply of energy from and to atmospheric eddies, Proc. Roy. Soc. Lond., A97, 354-373, 1920; J. E. Fjeldstad, Graphische Methoden zur Ermittelung adiabatischer Zustandsänderungen feuchter Luft, Geofys. Pub., vol. III, No. 13, Oslo, 1925.

The most suitable, perhaps, being Maxwell's classic Theory of Heat. Such as Planck's Vorlesungen über Thermodynamik (6te aufl., Berlin, 1921), or Poincaré's Thermodynamique (Paris, 1892). Cf. Nature, vol. 110, p. 207 (1922).

Perhaps Edgar Buckingham's Outline of the theory of thermodynamics (New York, 1900) came nearest to meeting this need.

Attention may also be called to P. W. Bridgman's convenient Collection of Thermo dynamic Formulae (Harvard Press, 1925).

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