December 1919 issue of the Monthly Weather Review, copies of which at 25c. each may be obtained from the Superintendent of Documents, Washington, D. C. Three others are scheduled for later issues of the Review.

Progress of American meteorology in 1919. Charles F. Brooks, Weather Bureau.

[An important advance in 1919 has been the firm establishment of an aeronautical forecasting service, by the Weather Bureau, based primarily on wind data for various levels telegraphed from a score of pilot balloon stations and 6 kite stations. The efficient aerological methods evolved during the war have formed the basis for further advances. The aerological chart used by the forecaster is in three dimensions. The papers summarized below give a view of the diverse lines of current meteorological progress.]

[American Year Book, 1919; contents of Monthly Weather Review, Nov., 1918 to Oct., 1919.]

Some meteorological paradoxes. W. J. Humphreys, Weather Bureau. [The most striking paradox is that more air goes up than ever comes down: considered by volume, this is due to the fact that warm air rises as cold, denser air comes down; considered by mass, it is true, for some of the rising air is water vapor which comes down in liquid or solid form.]

[Journal of the Washington Academy of Sciences, 1920.]

How the American Meteorological Society can serve geography teachers. Charles F. Brooks, Weather Bureau.

[The publication of meteorological and climatological notes and bibliography in the Bulletin of the Society, and of longer articles in the Monthly Weather Review, Journal of Geography, and, perhaps, School Science and Mathematics, will provide teachers with up-to-date material, and discussions of methods. Furthermore, teacher members of the Society can correspond with one another and learn to take full advantage of the opportunity to question meteorologists on different points, and about sources of information, class-room material, etc.] [Journal of Geography, (?), 1920.]

Use of laws in teaching climatology. Stephen S. Visher, Indiana University. [The complexity of climate can be made less disheartening by the use of summaries of the generalized facts of climate and their underlying physical principles. If the students know the essentials, say, "laws," the details may easily be added as needed.]

[Monthly Weather Review, 1920.]

Motion pictures of weather maps: a report of progress. J. Warren Smith, Weather Bureau.

[Scenarios have been outlined to show [1] the movement of a West Indian hurricane from beginning to end; [2] the movement of cold waves; [3] heavy rainfall and floods; [4] heavy snow storms; [5] local thunderstorms and tornadoes, and [6] comparisons of climate of different sections of the country. Scenes of storm damage, orchard heating, etc., and the work of the Weather Bureau will be included, as well as weather maps at short intervals.]

The work of the Weather Bureau in the West Indies. Oliver L. Fassig. Weather Bureau.

[The Weather Bureau maintains an extensive system of land stations and vessel radio-reporting stations for the purpose of finding and keeping track of West Indian hurricanes.]

Aims and achievements of the Blue Hill Observatory. Alexander McAdie, Harvard University.

[Annals. Astr. Obs. Harvard College, (?) 1920.]

Aerological work in the U. S. Navy. C. N. Keyser, U. S. N.

[The aerological work of the Navy is primarily for the purpose of providing detailed weather information for naval aviators and aeronauts, and for training the aerological officers enough to enable them to make local weather forecasts when they may be so situated as not to have access to Weather Bureau reports.] Plans for establishing a network of meteorological stations in Palestine. P. W. Etkes, New York.

[Funds have been set aside for the establishment of several first-order meteorological stations, and for a considerable number of secondary ones, mostly for the observation of rainfall.]

Determination of the normal temperature by means of the equation of the seasonal temperature variation and of a modified thermograph record. Frank L. West, N. E. Edlefsen, and S. P. Ewing, Utah Agricultural College.

[Daily and monthly march of normal temperature in the arid West may be approximated from a pair of formulas where bulky tables are not convenient.] [Jour. Agr. Research, Feb., 1920.]

The roaring of the mountain, and associated phenomena. W. J. Humphreys, Weather Bureau.

[In a West Virginia mountain region, the inception of a southeast, cross-ridge wind so focusses sound waves that sounds in a valley to windward and on the mountain top are magnified. A crest cloud forms and grows; the wind descends abruptly on a belt near the mountain, rebounds and forms a cloud roll; and after a few hours, precipitation ensues, verifying the prognostic of the "roaring" of the mountain.]

[Physics of the air, [revised], Franklin Institute, 1920.]

Some applications of radio-telegraphy to meteorology. J. C. Jensen, Nebraska, Wesleyan University.

[Not only can forecasts be transmitted easily by radio, but also the variations in the number of "strays" and in the sending radii of stations are so closely related to weather conditions as to suggest their use in making forecasts a few hours in advance.]

Sunshine in the United States. Robert DeC. Ward. Harvard University. [Two types of sunshine charts have been made: one showing the results of sunshine recorders and the other showing the reciprocal of cloudiness.] [Monthly Weather Review, Nov., 1919.]

Cloudiness in the United States. Robert DeC. Ward, Harvard University. [New cloudiness maps, generalized for classroom use, were presented. Cloudiness is at a maximum on the north Pacific coast, on the lee shores of the Great Lakes and in the north Atlantic States, and is much greater in winter than in summer.]

[Geogr. Review, 1919, vol. 8.]

The effect of a "lid" on the temperature and transparency of the lower air. Jacques W. Redway, Mount Vernon, N. Y.

[A warm stratum of air may act as a "lid" or ceiling at which convectional currents from below must stop and spread laterally. The presence of a "lid," therefore, tends to confine the haze and to make the daytime heating of the lower air easier, and, on account of the haze, the night time cooling more difficult.]

Weather conditions in the orchard regions of the North Carolina mountain slopes. H. J. Cox, Weather Bureau.

[Cold valley bottoms as well as cold mountain tops are normal. The warmest "thermal belts," between these two extremes are found where the mountain mass is small, the slope steep, and the opposite valley wall not close.] [Monthly Weather Review, Supplement, 1920(?).]

Preliminary steps in making free-air pressure and wind charts. C. LeRoy Meisinger, Weather Bureau.

[After a study of kite data from three stations it seems feasible to use surface wind-direction and surface temperature as indices to the mean temperature of the air column to the 1 or 2 kilometer level. From this and the surface pressure the pressures at the 1 or 2 kilometer level may be computed and used to construct accurate pressure (and wind] charts.]

[Monthly Weather Review, 1920.]

The prevailing winds of the north Pacific coast. A. E. Caswell, University of Oregon.

[The directions of the prevailing winds on the Pacific coast show where the center of the belt of highest pressure crosses the coast and where most of the low-pressure areas cross the shore-line. There are seasonal fluctuations, northward in spring and southward in autumn.]

Evaporative capacity. Robert E. Horton, Consulting hydraulic engineer, Voorheesville, N. Y.

[Experimental measurements of evaporation rates under different conditions of exposure and weather have made it possible to construct from temperature

and wind data maps showing the distribution of the "evaporative capacity" of the air in the United States.]

Device for obtaining maximum and minimum water surface temperatures. Robert E. Horton, Voorheesville, N. Y.

[A simple wooden framework is used to carry maximum and minimum thermometers with their bulbs just under water.]

Clouds and their significance. Charles F. Brooks, Weather Bureau.

[Clouds are our best indicators of atmospheric processes and movements. The cloud transformations during the passage of a winter cyclone give a fairly clear picture of the internal dynamics of such a storm.]

[Monthly Weather Review, 1920.]

Difficulties in the theory of rain formation. W. J. Humphreys, Weather Bureau.

[Rain is formed not by the falling of droplets and growth by collision with cloud particles, but by the condensational filtering of rising air at the cloud base, so that in the body of the cloud there are relatively few drops on which further condensation can take place.]

Cultivation does not increase rainfall. J. Warren Smith, Weather Bureau. [A study of the rainfall of the Great Plains during the last fifty years shows that wide fluctuations of rainfall have occurred, but the average of the first 25 years' rainfall is practically the same as that of the last 25 years. This indicates that the increased cultivation of the Great Plains has not altered the rainfall.]

Predicting minimum temperatures. J. Warren Smith, Weather Bureau. [When the relative humidity in middle or late afternoon is compared with the divergence of the minimum temperature during the coming night from the afternoon dewpoint, in clear and relatively calm weather, there is evident a welldefined relation for each place, which can be expressed by a parabolic curve. With such curves it is possible, as is now done in fruit regions, to predict the minimum temperatures with surprising accuracy.]

[Monthly Weather Review, Supplement 16, 1920.]

Seasonal distribution of maximum floods in the United States. A. J. Henry, Weather Bureau.

[The maximum flood is conditioned primarily upon the intensity and distribution of the precipitation, and the varying magnitudes from time to time. The absolute maximum flood on a stream is generally 1/4 to 1/4 times as great as the average of the annual maximum floods. The flood season in any region is usually that of heaviest rains, especially if they come in the snow-melting period.]

Weather and business. A. W. Douglas, Simmons Hardware Co., St. Louis. [The fact that the probable weather of a coming season can be computed somewhat better than it can be simply guessed at is worth recognizing in those businesses, such as the wholesale hardware, which depend closely on the weather. Also, it pays to watch day-to-day forecasts for impending important and widespread changes of weather.]

[Two U. S. Chamber of Commerce Bulletins, 1919.]

Explanation of peculiarities in flying in the wind. J. G. Coffin, Curtiss Engineering Corporation, Garden City, L. I., N. Y.

[As there is usually an increase of wind with altitude, climbing against the wind is much favored. This increase of wind aloft also affects the turning of an airplane in consequence of one wing being in a wind stronger than that blowing on the other wing.]

[Aviation, New York, Dec. 1, 1919, vol. 7, p. 383-385.]

Determination of meteorological corrections on the ranges of guns. Waldemar Noll, Aberdeen Proving Ground.

[Observations of wind direction, velocity, pressures and temperatures at various heights must be converted into terms of ballistic wind, ballistic density, and even ballistic temperature. The temperature effect is directly involved when the projectile has approximately the speed of sound, which changes with the temperature. During rainfall even the water content of the air per cubic meter and its velocity of fall must be considered.]

Evidence of climatic effect in the annual rings of trees. A. E. Douglass, University of Arizona.

[The rings of the yellow pine in northern Arizona show varying thickness in marked correlation with rainfall. The sequoias of California show similar

characteristics. In less degree, climatic effects may also be detected by finding similarity in ring growth of trees over large areas.]

[See "Climatic cycles and tree growth. A study of the annual rings of trees in relation to climate and solar activity." Carnegie Institution of Washington, D. C., 1919. 127 pp. illus. plates. 26 cm.]

CONTENTS OF THE MONTHLY WEATHER REVIEW.

Each month there are published in the Monthly Weather Review (Government Printing Office, Washington, D. C., printed for the Weather Bureau) (a) 40 or 50 quarto pages of original meteorological articles, abstracts, reviews, and notes, (b) two or three pages of current meteorological bibliography, divided into publications received by the Weather Bureau Library, and recent papers bearing on meteorology and seismology, (c) a page or two of observations of solar radiation intensities, including daily values of the "solar constant of radiation," (d) 10 pages of text, 5 of tables and 10 or 15 charts dealing with the weather of the month in the Pacific Ocean, North America (especially the United States), the Atlantic Ocean (for which some weather maps are published), and scattered portions of the world, and with weather warnings, rivers and floods, and weather and crops, in the United States, and (e) about 5 pages of earthquake information. The original articles published in the November 1919 issue of the Monthly Weather Review, just issued are as follows:

Variation in the total and luminous solar radiation with geographical position in the United States. H. H. Kimball. (23 figs.)

[AUTHOR'S SYNOPSIS.-The measurements of solar radiation intensity at normal incidence made at Washington, D. C., Madison, Wis., Lincoln, Nebr., and Santa Fe, N. Mex., have been utilized in determinations of the intensities for the Atlantic Coast States, the Plains States, and the Rocky Mountain plateau, at latitudes 30°, 36°, 42° and 48° N., at hourly intervals, on the 21st day of each month. Corresponding determinations of the intensity of the radiation received on a horizontal surface, and of the total radiation per day, have been made from the vertical component of the normal intensities, and measurements by the Callendar recording pyrheliometer of the diffuse radiation received on a horizontal surface from the sky. The variations in the daily totals with altitude and with cloudiness have also been determined.

From the relation between the total solar or heat radiation and the visible or luminous radiation, determined by means of synchronous pyrheliometric measurements made at Mount Weather, Va., in 1913-14, the solar radiation intensities at normal incidence above described have been converted into illumination intensities at normal incidence, and on vertical surfaces facing S., Sw., W., NW., N., NE., E., and SE. Also, the total illumination on a horizontal surface from the sun and sky has been determined for clear sky and completely overcast sky conditions.

Most of the results are shown in both tables and charts, the latter consisting of isopleths of heat or of luminous solar radiation, with hour angles of the sun as ordinates and days of the successive months as abscissas, except that the daily totals of radiation on a horizontal surface on the 21st of each month are shown by means of radiation isograms on outline maps of the United States.

The effect of surface slope on solar radiation intensities is brieby considered.] [Requests for separates may now be addressed to the Chief, U. S. Weather Bureau, Washington, D. C., and will be honored as far as limited supply permits.]

Bibliographic note on sunshine in the United States. R. DeC. Ward.

Note on comparisons between pyrheliometers and on the difference between Ångström standard and the Smithsonian Standard. A. Ångström.

A new instrument for measuring sky radiation. A. Ångström. (2 figs.) Some problems relating to the scattered radiation from the sky. A. Ångström. (Fig.)

Temperatures in New York Subways. (2 figs.)

[Temperatures after the beginning of operation were 11 to 20° F. higher than before. Could this have been due to the combined effect of human and mechanical heat? Before operation the average temperature, about 54° F. nearly coincided with the mean annual temperature of the air at New York City, 52° F. The range of average temperature 39° to 69° F. in the subways is only two-thirds the range of mean monthly air temperature at New York City. Cold days outside are cold days in the subways and warm days are warm outside and in: evidently the ventilation is good. The temperature variability is less than half as great in the subways as outside.]

Parade ground temperatures at College Station, Tex. C. F. Brooks.

[On the afternoon of a sunny June day when the air temperature was 101° F., the temperature of the dry dust in the sun was 142° F. and that of short, green grass, 120° F.]

Forecasting tide stages in the harbor at Portland, Oregon. E. L. Wells (2 fi s.)

[When the water in the Willamette River is low, tides are felt at Portland about 6 hours after the corresponding phases pass the mouth of the Columbia R. With high on-shore winds unusually high tides are sometimes experienced.]

An interesting observation of atmospheric ozone. H. I. Baldwin.

[On the summit of Haystack Mountain [4918 ft.], Sept. 8, 1919, a very strong, pungent odor [probably ozone] was smelt in passing wisps of cloud. The ozone (?) seems to have been formed by silent electrical discharges.]

There are also 24 abstracts or notes, many of them on topics closely associated with the original articles mentioned.

SOME WEATHER BUREAU PROJECTS.

The Congressional document giving an account of the Agricultural Appropriations Committee hearings relative to the Weather Bureau estimates for the coming fiscal year brings out some interesting developments of Weather Bureau work which may begin July 1.

Aerological work. The largest item is an increase of $200,000

"For the establishment and maintenance of additional aerological stations, for observing, measuring, and investigating atmospheric phenomena, and the issuing of weather forecasts, advices and warnings in the aid of military, naval, and civil aeronautics, and in the development of the navigation of the air, including salaries, travel, and all other expenses in the city of Washington and elsewhere."

Marine meteorology.-The next largest item is for $50,000 "For the extension of marine meteorological work, the collection of weather and water temperature reports at sea, the preparation of charts, the determining of fog zones, the distribution of marine meteorological information in the aid of navigation, and to carry out the provisions of the act of Congress approved June 17, 1910 (36 Stat. L., p. 508), for the collecting and furnishing of meteorological information to the Hydrographic Office of the Navy Department for use in the preparation of pilot charts, including salaries, travel, and other expenses in the city of Washington and elsewhere." Forest-fire warnings.—$15,000 is asked

"For the establishment and maintenance of special stations in national forests and elsewhere, the collection of reports and issuing of forecasts and warnings in connection with th protection of forests from fires, in coöperation with the Forest Service, State and other organizations, including salaries, travel, and other expenses in the city of Washington and elsewhere." Miscellaneous.-A number of other items for which additional funds may be appropriated are as follows: