116 EXPERIMENT STATION RECORD. 



Forests and rainfall, E. Henry (Indian Forester, 3-} (1908), No. 2, pp. GO- 

 SI). — This is an English translation of the original French article. A previous 

 article in the same series dealt with the levels of underground water in and 

 outside of forests (E, S. R., 18, p. 942). 



The present article discusses the moisture content of the air over forests and 

 open laud, and the influence of forests upon rainfall and the flow of springs. In 

 the previous article it was shown that the ground water level was much lower 

 under forests than under adjacent open land. The conclusion is drawn from 

 the data reported in this article tliat the moisture content and the chances of 

 lain are much greater over forests than over open land. It is stated that obser- 

 vations made in various localities show that forests increase the rainfall 8 to 15 

 per cent above normal. Forests also exert a beneficial influence in maintaining 

 a more uniform flow of springs. The foregoing conclusions, liowever, apply- 

 more particularly to level country. The pi-oblem is more complicated in hilly 

 or mountainous areas. It is i-ecognized that the chief factor affecting i-ainfall 

 is the conflguration of the ground, but it is maintained that other conditions 

 being equal wooded hills are better agents for promoting precipitation than bare 

 hills. Experimental data on this point are, however, deficient. 



The level of underground water in forests and in the open, P. Ototzky 

 iAn7i. Sci. Agron., 3. ser., 2 {1901), I, pp. 116-119). — This is a review of the 

 contents of a 2-volume book by Ototzky on Underground Waters, Their Origin, 

 Regime, and Distribution, which contains an account of investigations on the 

 subject of this article made in Gascony in 1902, showing, as many other obser- 

 vations had done, that the level of the ground water is lower under forests than 

 in the open. (See also E. S. R., 16, p. 672.) 



The level of subsoil waters with regard to forest, R, S. Pearson (Ann. 

 Sci. Agron., 3. ser., 2 (1907), I, pp. 10-'f-115). — A French translation of an 

 article already noted (E. S. R., 18, p. 942). 



Recent changes of methods and equipment in the water resources work of 

 the United , States Geological Survey, J. C. Hoyt (Engin. Xeics, 60 (1908), 

 Wo. 1, pp. 15, 16, figs. 2). — Several changes in the instruments and methods used 

 in stream gaging by the Water Resources Branch of the U. S. Geological Survey 

 are described. 



Effect of low temperature on bacteria in ice, J. C. Sparks (Sci. Amer. Sup., 

 65 (1908), Xo. 1695, pp. JflO, Jtll). — Tests are reported in this article from which 

 the conclusion is drawn " that ice, even when cut from water which may contain 

 pathogenic bacilli, is utterly incapable of passing on disease if it is stored for 

 some time before being distributed." 



Sewage purification works of the State Agricultural School, St. Anthony 

 Park, Minn., F. II. Bass (Engin. News, 59 (1908), No. 26, pp. 685, 686, figs. 

 Jf). — The consti'uction and efficiency of these works, which consist of a septic 

 tank, a percolating filter, and a sand filter and cost about $9,000, are described. 



SOILS— FERTILIZERS. 



Soil Studies, II: Acid soils, A. W. Blair and E. J. Macy (Florida Sta. Bui. 

 93, pp. 45-69, figs. 2). — This bulletin reports the results of an investigation 

 which was undertaken to find out to what extent acid soils are distributed in 

 Florida and discusses the origin and nature of Florida soils with reference to 

 the causes of acidity. 



Of 189 samples of soils and subsoils, representing 17 counties of the State, 

 68.22 per cent of the soils and 51.35 per cent of the subsoils were found to be 

 more or less acid when tested by A'eitch's limewater method (E. S. R., 16, p. 14). 

 ' With only one or two exceptions the soils are more acid than the subsoils, 



