METEOROLOGY — WATER. 815 



the flow of streams, and the color of the water. These observations to be of 

 interest to agriculture must be accompanieil by a precise knowledge of the 

 physical character of the soil studied. 



Is the earth drying- up? J. W. Gbegory (Gcogr. Jour., Jf3 (1914), Nos. 2, pp. 

 148-172, figs. 3; S, pp. 29S-31S). — The evidence bearing on this subject is sum- 

 marized in this article from a great variety of sources and for various parts 

 of the world. 



The general conclusion Is that " there have teen many widespread climatic 

 changes in late geologic times, while in historic times there has been no world- 

 wide change of climate." 



An extensive bibliography of the subject Is appended. 



Is South Africa drying upP R. von Gernet (Agr. Jour. Union So. Africa, 

 7 {1914), No. 1, pp. 47-50). — The author maintains that South Africa has been 

 undergoing a process of desiccation, not only for the last 30 or 40 years but for 

 thousands of years. He states "that the water courses cany less water than 

 of old, springs and si)ruitK give out even before the water has boon taken out 

 for irrigation, soft rains of long duration are rare, instead of which we are 

 getting torrential and short downpours doing a lot of harm by erosions while 

 the water is running to waste." 



This condition is attributed to slow geologic processes resulting in the uplift 

 of the land and the more recent influences of deforestation. The construction of a 

 system of dams and resor\-oIrs to store flood waters is urged as a remedy for 

 the unfavorable conditions. 



Secular variation of precipitation in the United States, A. J. Henry (Bui. 

 Amer. Geogr. Soc, 46 {1914), No. 3, pp. 192-201, figs. 3).— The available pre- 

 cipitation data for the past 40 or 50 years are summarized in tables and dia- 

 grams and are discussed with reference to the country as a whole and to 

 •various districts. The author concludes that the data lend "no color to the 

 theory of a cycle in precipitation . . . but in practically every case con- 

 firm the conclusion that the occurrence of wet and dry years seems to be 

 wholly fortuitous so far as the United States are concerned." 



The observations are thought to show that the probability that heavy rains 

 will occur in all parts of the country in one and the same year is very small. 

 " On the other hand, diminished precipitation over great areas seems to occur 

 with much greater frequency than increased precipitation. The tendency in 

 nature, as shown by the summary of the last quarter of a century, seems to be 

 toward years of lean rainfall, while years of fat rainfall seem to bo due to 

 an extraordinary deflection or disturbance in one or more of the dominant 

 members of the atmospheric circulation." The figures make it clear In general 

 that precipitation varies not only from year to year but also as between the 

 different parts of the country. 



The snowfall about the Great Lakes, C. F. Brooks {Abs. in Science, n. ser., 

 89 {1914), No. 1003, pp. 429, 4S0).— This is an abstract of a paper read at the 

 tenth annual meeting of the Association of American Geographers at Princeton, 

 N. J. It is explained that " the snowfall in this region is heavy because of 

 much moisture precipitated at low temperature by the many winter cyclones. 

 On account of the cooling action of land on the prevailing west winds blowing 

 across the lakes, the east shores got more snow than the west. Ice on the 

 lakes, by diminishing evaporation, reduces the snowfall of the leeward shores. 

 Thus the heaviest snowfall comes early in winter on the east shores, in marked 

 contrast with the late winter maximum on the west shores." 



Nitrogen and chlorin in rain and snow, G. II. Wiesner {Chcm. Xeivs, 109 

 {1914), No. 2830, pp. 85-87).— The nitrogen and chlorin content of 22 Siimples of 

 rain and 9 of snow collected at Mount Vernon, Iowa, from February 22 to 



