AGEICULTURAL CHEMISTRY. Ill 



upon the analysis of lemonade goods containing apple juice is discussed with 

 special reference to the detection of added coloring matter. 



The determination of carbon, I. Pouget and D. Chouchak {Bui, Soc. Chiin. 

 France, 4. ser., 3 (1908), So. 2, pp. 75-80; ahs. in Chem. Ahs., 2 (1908), No. 8, 

 p. 1105; Analyst, 33 (1908), Xo. 385, p. 1^2).— In the method described carbon 

 is determined in soils by combustion with lead chromate and potassium 

 bichromate, the carbon dioxid and nitrogen evolved being collected in a gas 

 holder over mercury upon which floats a measured quantity of one hundredth- 

 normal barium hydrate, the barium hydrate being finally titrated with one 

 hundredth-normal sulphuric acid. 



Determination of phosphoric acid, W. Pawlenko ( Vycstnik Sakh. Promuish., 

 1906, Xo. 37, p. 417; abs. in Cenibl. Zuckerindus., 16 (1908), Xo. 21, p. 582).— 

 Comparative tests are reported which indicate that alkaline magnesia mixture 

 gives as accurate results as the neutral mixture recommended by Jiirvinen. 



Alkalimetric estimation of phosphoric acid by Neumann's method, J. I*. 

 Gregersen (Ztschr. Physiol. Chem., 53 {1907), Xo. 6, pp. 453-463; abs. in Jour. 

 Chem. Soc. [London], 9^ {1908), Xo. 543, II, p. 64; Ztschr. Angcw. Chem., 21 

 {1908), Xo. 11, p. 498). — As a result of his investigations the author prescribes 

 the following precautions as necessary to the best results with the Neumann 

 method : In the destruction of the organic matter and the incineration of the 

 material use 20 ec. of Neumann's acid mixture, adding from time to time during 

 the process small amounts of concentrated nitric acid instead of the mixed 

 acids. In precipitation use 250 cc. of liquid containing 15 per cent of 

 ammonium nitrate, heat to TO to 80° C, and add a slight excess of 10 per cent 

 ammonium molybdate. In the final titration add a slight excess of standard 

 acid, boil to remove carbon dioxid. and titrate back with one-half normal 

 sodium hydroxid. 



Determination of free sulphuric acid in superphosphates, A. Pomaski 

 {Yyestnik Sakh. Promuish., 1907, Xo. 50, p. 765; abs. in Cenibl. Zuckcrindus., 

 16 {1908), Xo. 20, p. 552).— The method is in brief as follows: Shake 30 to 

 50 gm. of a finely ground superphosphate with 150 cc. of water-free ethyl 

 alcohol for ^15 to 20 minutes at room temperature with exclusion of air. 

 Neutralize an aliquot of the solution thus obtained with sodium hydroxid and 

 evaporate to dryness. Take up the residue in a little water, strongly acidify 

 with hydrochloric acid, and determine sulphuric acid with barium chlorid in 

 the usual way. 



Industrialization of analysis. Methods and apparatus used in the deter- 

 mination of nitrog'en and phosphoric acid in fertilizers, H. Rousset {Rev. 

 Gen. Chim., 10 {1907), Xo. 6, pp. 105-113; abs. in Chem. Abs., 1 {1907), Xo. 12, 

 p. 1601). — It is stated that the industrial chemist is as a rule intei-ested mainly 

 in matters of routine and desires chiefly knowledge of apparatus and methods. 

 This article gives a general account of apparatus and methods used at the Aisne 

 agricultural station in a large number of routine determinations of nitrogen 

 and phosphoric acid in fertilizers. 



On the determination of hardness, as well as free, partly combined, and 

 combined carbon dioxid in waters, H. Noll {Ztschr. Angeic. Chem., 21 {1908), 

 Xo. 14, pp. 640, 641; abs. in Chem. Abs., 2 {1908), Xo. I4, p. 1942).— A compari- 

 son is reported of Lunge's method of determining combined carbon dioxid in 

 water by titrating with hydrochloric acid in the cold, using methyl orange as 

 an indicator, with the method in which a given volume of water is boiled with 

 a measured amount of standard sulphuric acid and the carbon dioxid calculated 

 from the amount of unused sulphuric acid. The Lunge method was found to 

 give accurate results for the combined carbon dioxid, while the other method 

 gave results nearly a third too low. 



