718 EXPERIMENT STATION RECORD. F Vol. 43 



" In all the Kooky Mountain region it becomes niore dinicult to establish a 

 ratio between the annual precipitation and rate of grazing because of seasonal 

 distribution of precipitation, temperature variations, the topography, soil, 

 evaporation, snow cover, nature of the vegetation, and differences in the length 

 of the grazing period. In the central and upper Rockies the grazing rate is 

 slightly greater with small rainfall amounts than farther east, because of the 

 shorter gi-azing period, but less than in the Great Thiins with heavier precipi- 

 tation, because of the relatively less grazing areas in the higher mountains, 

 where the greatest precipitation occurs." 



Agricultural meteorology, .1. W. Smith {U. .S'. Mo. Wcatltei- Ret:, .'/S {1920), 

 No. 5, pp. 2S1-2S3). — The historical development of agricultural meteorology or, 

 as it may be broadly termed, meteorology in its relation to agricultui'e, is 

 briefly revie\Aed, the present work of the Division of Agricultural Meteorology 

 in the U. S. Weather Bureau is described, and future lines of development of 

 such work are discussed. The more important contributions to the subject 

 are indicated and a bibliography is given. 



The bioclimatic law, A. D. Hopkins (Jour. Wash. Acad. Sci., JO (1920), 

 No. 2, pp. SJf-JfO; ahs. in U. S. Mo. Weather Rev., 48 {1920), No. G, p. 355). — 

 This is a brief exposition of the bioclimatic law whieli has been more fully ex- 

 plained, particularly in its relation to various phenological events, in articles 

 noted (E. S. R., 43, p. 509). 



Intensity of nocturnal radiation at high altitudes, A. Botjtauic {Com pi. 

 Rend. Acad. Sri. [Paris], 170 {1920), No. 20, pp. 1195, 1196; ahs. in U. S. Mo. 

 Weather Rev., ^8 {1920), No. 5, p. 284; Rev. Sci. [Paris], 58 {1920), No. 11, p. 

 348). — Observations on Pic du Midi at an elevation of 2,859 meters, and at Mont- 

 pelier, practically at sea level, are cited to show that the intensity of nocturnal 

 radiation is independent of altitude when the temperature and vapor pressure 

 are the same. 



Monthly Weather Review {U. S. Mo. Weather Rev., 48 {1920). Nos. 5, pp. 

 251-310, pis. 16, flf/s. 20; 6, pp. 311-377, pis. 13, figs. //J).— In addition to de- 

 tailed sunnnaries of meteorological, climatological, and seismological data and 

 weather conditions for May and June, 1920, and bibliographical information, 

 reprints, reviews, abstracts, and minor notes, the.se numbers contain the follow- 

 ing contributions : 



A"o. 5. — Preliminary Steps in the Making of Free-air Pressure and Wind 

 Charts (illus.). by C. L. IMeisinger ; Detection of Storms and Their Travel by 

 Radio Equipment, by G. N. Keyser ; Aerological Observations in the West Indiio; 

 The Measurement of Temperature, With Some Remarks on other Physical Meas- 

 urements, and Applications to Meteorology, by E. W. Woolard ; Shading Instru- 

 ment Shelters (illus.), by S. D. Flora; The Standard Atmosphere, by W. R. 

 Gregg ; Intervals Between Beginning of Rainfall in West and Central France ; 

 The Most Intense Rainfall on Record, by B. C. Kadel; Sunshina and Cloudiness 

 in the Canal Zone (illus.), by H. G. Cornthwaite; Humidity and Hot Weather, 

 l)y H. G. Cornthwaite; Note on Dr. Griffith Taylor's Climograph Charts; and 

 Agricultural Meteorology, by J. W. Smith (see above). 



No. 6. — Relation Between the Annual Precipitation and the Number of Head 

 of Stock Grazed Per Square Mile, by J. W. Smith (see p. 717) ; New Aerological 

 Apparatus (illus.), by S. P. Fergusson; A General Theory of Halos (illus.), by 

 C. S. Hastings; Beautiful Halo Display Observed at Ellendale, N. Dak. (illus.), 

 by F. J. Bavendick; The Boulder Halo of January 10, 1918 (illus.), by E. W. 

 Woolard ; The Grand Junction Halo of March C, 1906 (illus.), by E. W. Woolard; 

 Outline Showing the Formation of the Elements of a Halo Complex, by E. W. 

 Woolard ; Iridescent Clouds, by C. F. Brooks ; Some Observations on a Free- 



