1919] AGRICULTURAL CHEMISTRY — AGROTECHNY. 415 



Biochemistry of Bacillus acetoethylicum with reference to the formation 

 of acetone, J. H. Northrop, L. H. Ashe, and J. K. Senior (Jour. Biol. Chem., 39 

 {1919), No. 1, pp. 1-21, fig. 1). — The biochemical studies leading to the develop- 

 ment of the process noted above are described in detail. 



The production of acetone and butyl alcohol by a bacteriological process, 

 H. B. Speakman (Jour. Soc. Chem. Indus., 38 (1919), No. 12, pp. 155T-161T, 

 figs. 7). — This paper deals with the production on a factory scale of acetone and 

 butyl alcoliol by the bacterial fermentation of a concentrated corn mash. 



Contribution to the bacteriology and technology of the preservation of 

 meat, A. Kossowicz and R. Nassau (Wiener- Tierdrztl. Monatsschr., 3 (1916), 

 No. 3, pp. 81-102, figs. 2; abs. in Chem. Abs., 11 (1911), No. 17, pp. 2508, 2509).— 

 This is a discussion of the methods of canning meat commonly employed in 

 Germany and of the causes of spoilage in the canned products. 



Proteus vulgare and Bacillus putrificus are the two organisms considered by 

 the authors to be the most important causes of spoilage. Perfect sterilization 

 of the cans is said to be attained with a temperature of approximately 120° C. 

 for 60 minutes. 



Studies on the preparation of vegetable decolorizing carbons for the cane 

 sugar industry, F. W. Zerban, E. C. Freeland, and D. D. Sullivant (Louisiana 

 Stas. Bui. 167 (1919), pp. 44). — The investigation reported in this bulletin com- 

 prised three phases : The preparation of decolorizing carbons from organic ma- 

 terials by impregnation with mineral substances and a comparative study of 

 the resulting efficiency ; the preparation of decolorizing carbons from materials 

 impregnated by nature or by some manufacturing process ; and the preparation 

 of carbons from by-products and similar materials. 



For the first study, the raw material generally employed was the sawdust of 

 long-leaf yellow pine (Pinus palustris) and the impregnating material, well- 

 defined chemical compounds — acids, bases, halids, and other salts. A definite 

 amount of the sawdust was mixed with the different impregnating compounds 

 in chemically equivalent quantities and subjected to similar methods of treat- 

 ment, involving a final heating for two hours in a muffle furnace at about 900° C. 

 After leaching with suitable solvents and washing with dilute hydrochloric acid 

 and finally with water, the resulting carbon was dried at 105°. The decolor- 

 izing effect for sugar products of the carbons thus prepared was determined 

 by adding 5 gm. of the carbon to 200 cc. of a standard molasses solution con- 

 taining 30 gm. per liter of a final molasses. The mixture was brought to the 

 boiling point, filtered through a folded filter, and the color determined by the 

 use of the tint-photometer as described in a previous bulletin (E. S. R., 41, p. 

 203). The efficiency of each carbon was calculated from the color remaining in 

 the treated solution in terms of Norit used as a standard. From the results 

 of the impregnation tests, which are given in tabular form, the following con- 

 clusions may be drawn : 



Organic nitrogen added to or present in the raw material increases the de- 

 colorizing power of the resulting carbon. Materials which are either gaseous or 

 solid at the temperature of final heating produce effective carbons, while those 

 which are liquid give poor ones. Compounds which attack carbohydrates most 

 vigorously give effective carbons if liquids are not formed at the temperature 

 of final heating. The fineness of division of both raw material and impreg- 

 nating substance has a favorable effect on the resulting carbon. The decolor- 

 izing power of the carbon increases directly with the quantity of impregnating 

 substance used per unit of raw material. The method of preliminary carbon- 

 ization and the temperature of final heating influence the decolorizing power of 

 the carbon. The first heating should be conducted in such a way that the 



