RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY. 



Technical methods of chemical analysis, edited by G. I.unge et al., trans, 

 and edited by C. A. Keane et al. {London, 190S, vol. 1, pts. 1, pp. XX1V+ 

 1-519, figs. 1J,6; 2, pp. X+520-996, figs. .55).— This is a translation of the latest 

 German edition, adapted to English conditions of manufacture. The sections 

 of the booli of special interest from an agricultural standpoint are those re- 

 lating to potassium salts, calcium compounds, drinking water and water sup- 

 plies, sewage and effluents, soils, and air. The articles on the various subjects 

 included in this book have been prepared by specialists in the different lines. 



Colorimetric determination of phosphoric acid, I. Pouget and D. Chouchak 

 (Ann. Chim. Anulyt., U, (1909), No. J,, pp. 125-129; Zhur. Opuitn. Agron. [Russ. 

 Jour. Expt. Land.], 10 {1909), No. 2, pp. 129-134; abs. in Analyst, 34 (1909), 

 No. 397, pp. 17S, 179; Ztschr. Angeiv. Chem., 22 (1909), No. 16, p. 738).— These 

 are further references to accounts of a method already noted (E. S. R., 20, 

 p. 703), which is based upon the turbidity produced when an alkaloid (strych- 

 nin) is added to a solution containing sodium molybdate, nitric acid, and phos- 

 phoric acid. 



The colorimetric estimation of phosphates in solution "with other salts, 

 C. EsTES {Jour. Amcr. CItcm. Soc, 31 (1909), No. 2, pp. 2'i7-250; aha. in Jour. 

 Soc. Chem. Indus., 28 (1909), No. 5, p. 261; Analyst, 34 (1909), No. 397, p. 179; 

 Jour. Chem. Soc. [London], 96 (1909), No. 557, II, p. 266').- Investigations of 

 the influence of different salts upon the color obtained in the use of the ammo- 

 nium molybdate colorimetric method showed that the error in reading does not 

 exceed 5 per cent with a maximum of 5 parts of sodium sulphate. 10 parts of 

 potassium nitrate or magnesium sulphate, 15 parts of potassium hydrogen sul- 

 phate, 20 parts of calcium nitrate, magnesium nitrate, or sodium chlorid, 30 

 parts of potassium ethyl sulphate, or 50 parts of sodium nitrate per 10.000 

 of the solution. 



Gravimetric determination of phosphorus in cast iron and steel as ammo- 

 nium phosphomolybdate, G. Ohesneau (Rev. Metal., 5. pp. 237-269; abs. in 

 Chem. Abs., 3 (1909), No. 7, pp. 760, 761).— A somewhat detailed study of the 

 conditions affecting the accui'acy of this method is reported, and the precau- 

 tions to be observed in order to obtain precise results are described. 



The determination of phosphoric acid by weighing the ammonium phos- 

 phomolybdate, II. Pellet (Ann. Chim. Anulyt., 14 (1909), No. 1. pp. 7-11; 

 abs. in Jour. Chem. Soc. [London], 96 (1909), No. 556, II, p. 182; Ztschr. 

 Angew. Chem., 22 (1909), No. 22, p. 1026; Chem. Zentbl., 1909, I, No. 18, p. 

 1504). — This is a review of the article by Chesneau, noted above. The condi- 

 tions affecting the accuracy of this method of determination as applied by 

 Chesneau to iron and steel and by the author to soils, fertilizers, etc., are dis- 



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