212 EXPERIMENT STATION RECORD. 



to South Australian conditions the author briefly discusses rainfall, its use 

 and loss, artesian water, artesian basins, the salt content of rain, ground 

 water, well types, factors determining quantity and quality of water, well loca- 

 tion and protection, tanks, and the use of the divining rod. Observations made 

 in New Zealand are said to prove that every inch of rain falling over an acre of 

 ground deposited 4f lbs. of salt. 



The advice of a geologist is considered preferable to that of a diviner in 

 locating underground water supplies. 



SOILS— FEETILIZEES. 



The geology of soils and substrata with special reference to agriculture, 

 estates, and sanitation, H. B. Woodward {London and New York, 1912, pp. 

 XVI -{-366, pis. Jf, figs. U; rev. in Science, n. ser., 38 (1913), Wo. 983, pp. 626, 

 627). — This book gives an outline of geology in its broader relations with agri- 

 culture and sanitation, and discusses the preparation of geological maps and 

 soil surveys; soils, subsoils, and substrata; weathering of rocks and subsi- 

 dences; the climatic conditions affecting soils and their handling; chemical 

 composition and physical properties of soils; the use of mineral fertilizers and 

 amendments; forests and woodlands, and their associated geological features; 

 orchards, gardens, and vineyards ; geological considerations concerning minerals 

 and other economic materials ; house sites, water supply, sewage, and drainage ; 

 and geological formations of England in their relation to the above subjects. 



The object of the book is stated to be " to provide such information relating 

 to the land-surface as will be useful to students and teachers of agriculture, to 

 those occupied in the management of estates and farms, or in sanitary and 

 engineerng works, wherein it is important to consider the geological nature of 

 different sites for residences and other purposes." Special emphasis is laid on 

 the importance of a knowledge of the underlying formations in the study of 

 soils. It is maintained that a soil map to be of most value must deal not only 

 with the surface soil, but must take into account the subsoil and show the 

 depth as well as the nature of the soil. "A map of the surface soils alone 

 would give a very imperfect idea of the capabilities of the land. ... A good 

 subsoil map which shows the variations in the strata, whether drifts or the 

 more regularly stratified formations, will always indicate the general distribu- 

 tion of the surface soils." 



The germs of pedology in antiquity, A. Jaeilow {Internat. Mitt. Bodenk., 

 3 {1913), No. 2-S, pp. 240-256). — This article reviews the ancient ideas regarding 

 biology and physics of soils. 



Progress in agricultural chemistry (especially soil chemistry) since the 

 use of the newer results of physical chemistry, especially colloid chemistry, 

 H. Beehm {Kolloid Ztschr., 13 {1913), No. 1, pp. 19-35).— This article discusses 

 in some detail the significance of colloid chemistry 'in relation to soils, 

 mineralogy, and geology. The chief soil colloids enumerated are humus, slime 

 organisms, colloidal iron and aluminum hydroxids, weathered amorphous 

 silicates, and bacteria and micro-organisms held in suspension. The chemistry 

 of colloidal humus in soils and the influence of lime and humus on the 

 adsorptive power of cultivated soils are taken up in turn, followed by reviews 

 of numerous works on the quantitative determination of soil and decomposed 

 rock colloids. 



It is thought that colloids play an important part in the exchange of bases 

 when plant food is added to the soil by entering into the so-called adsorption 

 combinations which are essentially different from ordinary chemical combi- 

 nations. These colloidal cementing substances or adsorption combinations are 



