WATER-— "II.-. 757 



inir is not indicated as likely to be profitable unless the soil contains certain! 

 than 0.25 percent of chalk. Basic slag is nearly always a better source of phos- 

 phoric acid for pastures than superphosphate, unless perhaps when the soil contains 

 an exceptionally high percentage of chalk. 



"Pastures are not likely to be improved by manuring unless their soil contains fair 

 proportions of both large and small particles, and the effecl of manures is greater the 

 more regularly the various grades of different-sized particles are represented in the 

 stitution of the soil. 



•• Determinations of citric acid, soluble phosphoric acid, and potash, and of calcium 

 carbonate, and mechanical analysis of the soil, together with careful observations of 

 the herbage w hich the land in its unmanured condition is producing, may be expected 

 t>> indicate clearly those soils which are likely to be improved for pasturage by 

 manuring with phosphates and potash." 



Relation of yield to the amount of water-soluble plant food materials in 

 soils, F. II. Kin., Wa \ ...... . US). — The results of 



experiments on this subject are briefly summarized. 



Contributions to the chemical study of soils, waters, and mineral products 

 of the region of Chari and Lake Tchad. A. Hbbi . ,./. Acad, S 



[Farit], ' — A recent mission sent into these regions 



under the leadership of A. Chevalier collected numerous samples of geological, agri- 

 cultural, and industrial interest, including type soils onder cultivation >>r w hich bore 

 il useful plants coffee, cotton, Gossypium anomalum, etc, minerals and mineral 

 products, mineral efSores kali . and waters. 



All the soil- were very sandy and generally rich in nitrogen. There was, how- 

 ever, a considerable proportion of clay and sodium salts, but an almost entire absence 

 of lime, magnesia, potash, and phosphoric acid. The salts resulting from the evapo- 

 ration of the lake water in shallow estuaries were alkaline, emitting an odor of 

 ammonium or methylamin, and were composed largely of sodium sulphate, with 

 some potassium salts. Sulphids and considerable amounts of nitrogenous organic 

 matter were also present 



Preventing- soil washing. A. M. Soule ' South. Agr., 34 I 19 . p. 1). — 



Deep plowing and green manuring are the remedies proposed. 



Utilization of salt land. W. I.. Summ - •. and Ind. Smith Australia, 8 



.—A series of experiments with different crop- on alkali 

 lands in Southern Yorke Peninsula of South Australia is reported. These experi- 

 ments show that with proper methods of culture good yields of such crops as rape, 

 kale, mangels, and saltbush can he produced on these lands. 



Culture of the Landes, E. Leroui (Jour. Agr. PraL, ». aer., 8 [1904), 

 pp. 632-634)- — A brief general discussion is given of the best methods of bringing 

 these - lands under cultivation. 



Studies in nitrification. G. 8. Fraps North <'-n-ufn^i Sta. Rpt. 1903, /-/-. 33-54, 

 figs. t). — A detailed account of investigations briefly reported elsew ! - \\., 



14, p. - 



Nitrifying power of typical North Carolina soils. W. A. Withers and I 

 Frai - roKna >/,/. A'/./. 1903, pp. 57-63). — In this study it was found that ' 



the nitrifying power of 15 North Carolina soils varied from 11 to 106, thus showing 

 a irreat difference in the capacity of different soils to serve as media for the growth of 

 nitrifying organisms; (2) the soils with the lowesl nitrifying power are sands with 

 low water capacity, low humus, low absorptive power for ammonia, low acidity, and 

 a moderate amount of humus: (3) acidity of the soil did not prevent the growth of 

 the nitrifying organisms; (4) a soil \\ ith a low water capacity, low absorptive power, 

 or low bumus does not necessarily have a low nitrifying power." 



Nitrification of different fertilizers. W. A. With Era and G. S. Eraps (North 

 Sto. Rpt. 1903, pp. .:-■•: .—In continuation of investigations reported in a 



