METEOROLOGY WATER. 



509 



of stream action in normally moist lands. At any rate, erosionally, its world's 

 worlv is probably surpassed ueitlier by that of lij^drasiou nor by that of glacia- 

 tion." 



Nitrogen in rain and snow, N. Knight (Abs. in Science, n. set:, 33 (1911), 

 No. 862, p. 28). — Tliis is an abstract of a paper read before the Iowa Academy 

 of Science, as follows : 



" SeAenteen samples of rain and snow were collected on the college campus at 

 Mount Vernon, Iowa, during nine months of the year 1909-10. The nitrogen in 

 the free and albuminoid ammonia and in the nitrates and nitrites was deter- 

 mined. Comparisons were made of the relative amounts of nitrogen precipitated 

 with the rain and snow. According to the experiments, each acre would receive 

 in the nine months between 13 and 14 pounds of nitrogen from the rains and 

 snows." 



Cannonading against hail, .7. M. Ouillon (Jour. Agr. Prat., n. ser., 21 

 (1911), No. Ui, p. H2). — This is a brief account of organized efforts in France 

 to prevent hailstorms by cannonading. 



The climatic requirements for fruit culture, P. Holdefleiss (Ber. Landw. 

 licich-sumte liincrn [(Jcrinaiii/], 1010, No. 11, pp. 18-8(i). — This article discusses 

 the moistui-e, temperature, and sunshine conditions best suited to fruit culture. 



Rainfall distribution over the growing period of wheat, A. J. Perkins and 

 W. J. Spaffokd (Jour. Dept. Agr. So. Aust., Uf (1911), No. 10, pp. 96-'f-966).— 

 The distribution of rainfall and the yield of wheat from 1905 to 1910 on the 

 experimental field of the Roseworthy Agricultural College, South Australia, 

 are shown in the following table: 



Rainfall dintrlbatioti and yield of wheat at Roseworthy Agricultural College, 



1905-1910. 



The author concludes from his observations that the ultimate success of the 

 wheat harvest depends primarily on the existence of normal conditions at 

 seeding time followed by good growing winter weather. When the rainfall 

 during this i>eriod falls decidedly below the 6.35 in. shown in the table as the 

 mean of 27 years the ultimate yield is likely to suffer. 



The agricultural duty of water, W J McGee (U. S. Dept. Agr. Yearbook 

 1910, pp. 169-176). — The author discusses the relation of the soil to soil water, 

 soil-plant circulation, the ratio of crop to water supply, and the duty of water, 

 and finally reaches the conclusion that " in a broad way it may be said that the 

 final duty of water is to sustain a human life a year for each 5 acre-feet used 

 effectively in agriculture." 



Daily river stages at river gauge stations on the principal rivers of the 

 United States. Part X, For the years 1909 and 1910, H. C. Fkankenfield 

 (U. S. Dept. Agr., Weather Bur. Doc. 453, pp. 397).— This is the tenth of the 



