RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY. 



On the quantitative volatilization of phosphoric acid from phosphates in 

 a current of chlorin and carbon tetrachlorid or of tetrachlorid alone, P. 

 JannxVSCh and W. Jilke {Bci: Dcut. Chan. GescU., J,0 (,1901), 'No. 13, pp. 

 3605-3608, fig. 1; Jour. Pralct. Chem., n. ser., 78 (1908), No. 1, pp. 21-28; abs. 

 in Ztschr. AnaJyt. Chem., 1,1 (1908), No. 2-3, p. 162; Chem. Zentbl., 1908, II, 

 No. 4, pp. 3^8, 3ji9; Chem. Ztg., 32 {1908), No. 65, Repert., p. ^H).— This is an 

 account of a continuation of the worli by Jannasch and Heimann (E. S. R., 18, 

 p. 522), who found that phosphoric acid could be quantitatively volatilized by 

 heating with sugar and concentrated sulphuric acid in a stream of chlorin. The 

 later investigations show that the same result can be more easily obtained with 

 all kinds of phosphates by heating in a current of chlorin charged with carbon 

 tetrachlorid or of tetrachlorid alone. The apparatus required in the process is 

 described. 



A study of the solubility of potassium chloroplatinate, E. H. Archibald, 

 W. G. Wilcox, and B. G. Buckley {Jour. Amer. Chem. Soc, 30 {1908), No. 5, 

 pp. 747-760, figs. 3). — Studies of the solubility of potassium chloroplatinate in 

 water, potassium and sodium chlorid solutions, and different alcohols are re- 

 ported. It was found in these studies that : 



"(1; Small amounts of potassium chloroplatinate In solution can be esti- 

 mated colorimetrically with considerable accuracy. This will be true of any 

 salt which gives the PtCU anion, provided the color of the cathion is not such 

 as to interfere. 



" (2) The chloroplatinate is less soluble in solutions of ethyl alcohol and 

 water than in water solutions of either methyl or isobutyl alcohol. Only 

 0.0007 gm. of the salt dissolves in 100 cc. of ethyl alcohol at 20°. 



" (3) The solubility of the chloroplatinate in potassium chlorid solutions de- 

 creases with the increase in concentration of the potassium chlorid until a con- 

 centration of 1 gm. molecule per liter is reached. Beyond this point, increasing 

 the concentration of the potassium chlorid has practically no effect. 



" (4) The solubility of the chloroplatinate in solutions of sodium chlorid in- 

 creases rapidly until a concentration of 0.05 gm. molecules per liter is reached. 

 For more concentrated solutions the increase in solubility is small and almost 

 proportional to the increase in concentration of the sodium chlorid." 



The destruction of org'anic matter by electricity in the analysis of foods 

 and agricultural products, F. Scurti and O. Gasparina {Ann. R. Stuz. Chim. 

 Agr. Sper. Roma, 2. ser., 1 {1906-7), pp. 150-155). — The use of electricity for 

 the destruction of organic matter is, according to the authors, simple and gives 

 satisfactory results. 



The volumetric determination of hardness in potable waters, U. Milone 

 (Am 6. Cong. Internaz. Chim. AppL, 1 (1906), pp. 258-260).— A new degree 

 of hardness, viz, centigram of calcium per liter of water, is proposed, and the 



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