RECENT WORK IN AGRICULTURAL SCIENCE. 



AGEICULTURAL CHEMISTRY. 



A wax acid from soils, O. Schreiner and E. C Shorey (Abs. in Science, 

 n. ser., 28 (1008), No. 710, p. 190). — This is an abstract of a paper presented 

 at the recent meeting of the American Chemical Society at New Haven. 



" In the examination of a black clay loam from North Dakota there was 

 obtained by treatment with boiling 95 per cent alcohol a colored extract from 

 which a microcrystalline precipitate separated on cooling. By washing with 

 cold alcohol and recrystallizing, this can be obtained free of color. On drying 

 this pnrifled precipitate and treating with cold ether it is divided into two 

 portions. The other soluble portion crystallizes on evaporation of the ether 

 in minute leaflets, melting at 72-73° C. The physical and chemical properties 

 of this body place it among the fatty acids found in waxes. p]lemeutary 

 analyses correspond with the formula C21H42O3, the hypothetical acid of a 

 lactone found in caruauba wax. The name agroceric acid is proposed for 

 this body." 



The presence of a cholesterol substance in soils — agrosterol, O. Schreiner 

 and E. C. Shorey (Jour. Amer. Cliem. Soc, 31 (1909), No. 1, pp. 116-118; aU. 

 in Science, n. set:, 28 (1908), No. 710, p. 190). — This is a paper presented at 

 the recent meeting of the American Chemical Society at New Haven. It is 

 stated that "when the alcoholic extract of the soil referred to [above! is 

 separated from the precipitate, which forms on cooling, and is evaporated to 

 small volume, a resinous dark-colored mass is obtained. Cold ether dissolves 

 a portion of this, including the coloring matter. Spontaneous evaporation of 

 the ether leaves again a resinous dark-colored mass. Treatment of this with 

 cold absolute alcohol removes the coloring matter and leaves a white crystal- 

 line residue. Purification of this by recrystallization yields a body crystalliz- 

 ing in plates resembling those of phytosterol, melts at 237° and gives the 

 cholesterol reaction with acetic auhydrid and sulphuric acid. Elementary 

 analysis gave figures corresponding to the formula C-6H44O. The name agros- 

 terol is suggested for this compound." 



Critical observations on the Schone and Appiani methods of physical 

 analysis of soils, G. De Lucchi (Ann. R. Staz. Agr. Forli, 1907, No. 36, pp. 

 19-29). — As a result of comparative tests of these methods the author recom- 

 mends the Appiani (decantation) method as preferable to the Schone method 

 on account of its simplicity and rapidity. 



Application of the cobalti-nitrate method to the estimation of potassium 

 in soils, W. A. Drushel (Amer. Jour. ScL, //. ser., 26 ( 1908), No. 15h VP- 329-332; 

 Ztschr. Anorgan. Chem., .59 (1908), No. 1. pp. 97-101 ; abs. in Jour. Chem. Soc. 

 [London], 9J, (1908), No. 550, II, p. 735; Chem. Zentbl, 1908, II, No. 13. p. 

 1126).— In the application of the method already described (E. S. R., 19, p. 808) 

 to the determination of potash in soils, a weighed quantity of soil is extracted 

 on a water bath with 20 per cent hydrochloric acid, the acid removed by evap- 

 oration, and the bases separated by addition of sodium carbonate or ammonia 

 and ammonium oxalate. The ammonium salts and organic matter are removed 



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