526 EXPERIMENT STATION RECORD. 



Rollers at Mount Pleasniit, Mich, (illus.). by R. D. Calkins; Progress of 

 Meteorology in Australia; George J. Fleck; Physical Societies and Journals; 

 and Weather Bureau Men as Educators. 



No. 8. — The International Synilwls, by H. H. Clayton ; The Meteorological 

 Optics of Prof. J. M. Pernter (illus.), by R. W. Wood; Eiffel's "Etudes Pra- 

 tiques ; ■' Studies on the Therniodynanilcs of the Atmosphere — VII, The 

 Meteorological Conditions Associated with the Cottage City Waterspout (illus.), 

 by F. H. P>igelo\v : Variation in Temperature Over a Limited Area (illus.), by 

 W. I. Milham; The First Daily Weather Maps from China (illus.), by C. F. 

 Talman ; What is Research ; The International Seismological Association ; 

 and Astronomy versus jMeteorology. 



Climatology of Porto Rico from 1867 to 1905, inclusive, W. II. Alexander 

 (I/O. Wcatlicr Rev., 3.>t (1006), No. 7, pp. 31o-32-'i).— This article supplements a 

 previous report on the same subject, giving additional data regarding toi)ogra- 

 phy, which is based upon a bidletin of the U. S. Geological Survey, previously 

 noted (E. S. R.. 12, p. 795), and tabulated summaries of observations on tem- 

 perature, rainfall, etc.. at a number of places in Porto Rico, observations at San 

 Juan, Canovanas, and Perla being given in some detail. 



The data show a very uniform temperature, with no excessi^■e extremes, the 

 annual range rarely being 50°. January shows the coldest mean temperature 

 and August the hottest, the difference between the two, however, being only 

 5.1°. The extreme maxinmm temperature usually occurs in May. The mean 

 temperature of the period from December to April is below the annual mean of 

 the rest of the year above. The average daily range of temperature at San Juan 

 is between 11 and 12°, although at interior stations a much greater range is 

 recorded. The minimum daily temperature occurs about 5 a. m.. the maxinmm 

 from 10 a. m. to 2 p. m. The temperature decreases about 4° for each 1,000 ft. 

 of elevation. 



A well-defined dry season occurs from about November 2U to April 15, Febru- 

 ary being the dries*, month. The average number of rainy days is. 194 at Cano- 

 vanas, 208 at San Juan, and 2t)0 at Perla. The average rainfall for the east 

 coast is 92 in., for the north and west sides 80, for the south side 57. The rain- 

 fall in general decreases westward to the middle of the Island and then rapidly 

 increases. The south side is subject to long droughts, making irrigation 

 necessary. 



The steady northeast trade winds, light at night and fresh during the day. 

 make the evenings cool and even the hottest days less oppressive. The island is 

 out of the usual path of hurricanes and these are comparatively rare. Thun- 

 derstoruis :ind hailstorms are infreciuent and rarely violent. 



Climatological atlas of India, J. Eliot {[Calcutta]: Indian Met. Dcpt., 

 1906. pp. XXXII. pis. 120; rcr. in Nature [London], 75 (1907), No. 1941, pp. 

 2.'il-2.'iJt). — This atlas consists of 120 colored maps showing in great detail the 

 distribution of the meteorological elements over the Indian Empire, with an 

 introduction giving " a brief history of the progress of the work of meteorological 

 observation in India and hence of the growth of the Meteorological Department, 

 a list of the observatories contributing observations that have been utilized in 

 the preparation of the atlas with their position and elevation, and a brief 

 explanation of the charts." 



The maps are based upon the results of observations during the first 25 years' 

 operation of the Meteorological Department of India, be.ginning with the year 

 1875-76 and covering the incumbency of Sir John Eliot, and are classed as gen- 

 eral, pressure and wind charts, temperature maps, humidity chax'ts, cloud plates, 

 rainfall mai)s. and storm track charts. The work is reviewed in Nature by J. 



