RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



Organic chemistry for advanced students. — I, Reactions. II, Structure. 

 Ill, Synthesis, J. B. Cohen (New York: Longmans, Green d Co., 1918, 2. »■■/.. 

 pts. 1, pp. VIII+S66, fin*. ■',: 2, pp. VII+J,35, figs. 65; 3, pp. V// +378). —In the 

 second edition of this work, which is intended to furnish a general survey of 

 the fundamental principles which underlie the modern developments of organic 

 chemistry, the former two volumes have been rearranged in throe parts in 

 order to group together allied subjects. The subject matter has been revised 

 and brought up to date. 



An introduction to chemical German, E. V. Greenfield {Bo$ton: D. C. 

 Heath <£ Co., 1918, pp. XXIII+88/f). — This book consists of a series of selections 

 from German chemical literature with accompanying notes and vocabulary, 

 prefaced by an introductory chapter in which the peculiarities in German par- 

 ticipial construction and word composition are explained and a list of 500 words 

 recurring constantly in German chemical literature is given. 



New laboratory apparatus, H. Vigreux (Atm. Falaif., 11 (1918), No. ltl- 

 1..'.?, pp. 8S5-387, figs. 5). — Three forms of apparatus are described and illus- 

 trated by diagrams: (1) A distilling apparatus for ammonia determinations in 

 which large surfaces for condensation of moisture are provided by a tube and 

 condenser set with glass points, (2) a glass safety valve which has the advan- 

 tage of being demountable, and (3) a new condenser by means of which dis- 

 tillation can be carried on rapidly without resulting loss. 



Solubility of slag in weak organic acids, M. Rirot and G. Joret (Aim. Chim. 

 Analyt., 2. ser., 1 (1919), No. 3, pp. 80-85). — Determinations are reported of the 

 solubility of the different constituents of slag — phosphoric acid, carbonates, 

 iron, magnesium, and sulphur — in very dilute organic acids, such as are secrete | 

 by the roots of plants. The results, which are reported in tabular form, show 

 that all of these constituents as they exist in the slag are more or less readily 

 soluble in the dilute organic acids employed, and that to a certain extent slag 

 can serve as a composite fertilizer. 



Note on the electrolytic preparation of dilute sodium hypochlorite solu- 

 tions (Dakin's solution), G. E. CtJIXEN and R. S. Hrr.it.wii> {Jour. Hiol. Chcm., 

 37 (1919), No. If, pp. 519-52.1. figs. 8). — The strength of electrolytieally prepared 

 solutions of sodium hypochlorite is shown to depend upon temperature and salt 

 concentration. The recommendation is made that from experimental runs 

 curves showing the influence of these factors be constructed for each cell. 

 From the initial temperature of the solutions, the time required for a solution 

 of given concentration may then be determined. Ordinary 3 per cent sodium 

 chlorid (or sea water) is said to be satisfactory, but if necessary to operate 

 with relatively warm solution the salt concentrations should be increased. The 

 solution should be stabilized as soon as it comes from the cell by one of the 



methods noted above. 



To; i 



