256 abstracts: agricultural chemistry 



105° has little depressing action. Various inorganic substances and 

 several organic compounds, especially those in a state of partial oxida- 

 tion, have the power of decomposing hydrogen peroxide, while several 

 organic compounds increase the catalytic power of manganese cUoxide. 

 In general the catalytic power of soils seems to be due not to an en- 

 zyme, such as catalase, but rather to the inorganic and organic matter 

 working separately, conjointly, or in activating combination. 



M. X. S. 



AGRICULTURAL CHEMISTRY.— Some organic soil constituents. E. 

 C. Shorey. Bulletin of the Bureau of Soils, No. 88. 1912. 



The isolation of 15 organic compounds is described, 14 of which have 

 been identified. These together with those previously isolated and 

 described make 35 organic compounds isolated from soils. The sub- 

 stances here described belong to six classes of organic compounds, 

 three of which, 'aldehydes, organic sulfur, and organic phosphorus com- 

 pounds are classes not represented among those isolated and described 

 before. 



The compounds isolated have been classified as follows: 13 organic 

 acids, 9 organic bases, 3 sugars, 2 aldehydes, 2 alcohols, and 1 each, 

 hydrocarbon, glyceride, resin ester, sulfur compound, phosphorus com- 

 pound and an acid anhydride. The relationship between these groups 

 as well as that between the isolated compounds and the organic matter 

 in general is discussed. The compounds isolated and described here 

 are oxalic acid, succinic acid, saccharic acid, acrylic acid, lysine, aden- 

 ine, choline, trimethylamine, salicylic aldehyde, mannite, rhamnose, 

 trithiobenzaldehyde, nucleic acid, of unloiown constitution, and an 

 unidentified aldehyde. 



The conclusion is reached that the work, like that previously reported, 

 while it emphasizes the complex character of the organic matter of soils, 

 bears out the contention that this complexity is not so great but that 

 the chemical nature of all of the organic matter of soils can be deter- 

 mined by modern methods of research. M. X. Sullivan. 



AGRICULTURAL CHEMISTRY.— T/ie chemistry of steam-heated soils. 



Oswald Schreiner and Elbert C. Lathrop. Bulletin of the 



Bureau of Soils, No. 89. 1912. 

 This bulletin deals with the chemical changes involved when soils 

 are steam heated, as in the process of sterilization. The results may 

 be summarized as follows: (1) In accord with the work of other inves- 



