AGRICULTURAL CHEMISTRY AGROTECHNY. 9 



A new acidimetric method employing' lime water, A. de Geegoeio Rocaso- 

 LANo (Rev. R. Acad. Cien. Madrid, 7 {1908), No. 6, pp. 375-382, figs. 2; abs. in 

 Chein. Ztg., S3 (1909), No. 89, Repert., pp. 386, 387).— The volumetric limewater 

 solutiou method can be employed for hydrochloric, sulphuric, nitric, phosphoric, 

 oxalic, citric, and tartaric acids. The solution, prepared by saturating water 

 with lime, is siphoned off through a filter paper or membrane attached to the 

 proximal end of a wide bored siphon, and the siphon is in turn connected with 

 a burette. At each reading of the burette the temperature of the solution must 

 be taken and compared with a table appended by the author. The general for- 

 mula for calculation is also given. 



The accuracy of the Volhard method for the determination of chlorin, V. 

 Rothmund and A. Burgstaller {Ztsclir. Anoryan. Clicm., 63 (1909), No. J/, pp. 

 330-336). — According to the authors the Volhard method without filtering off 

 the silver chlorid is only accurate when rather lai'ge amounts of chlorid are 

 present and the solution is not too dilute. The addition of an excess of silver 

 nitrate has a favorable influence upon the reaction, but an excess of thio- 

 cyanate solutiou must be avoided in titratiug back. 



Aluminum as an impurity in barium sulphate precipitate, H. J. M. 

 Creigiiton (Ztschr. Anorgan. Clicin., 63 {1909). No. 1, p/). .JJ-.J.S, fig. 1). — The 

 presence of small amounts of aluminum salts in a solution has a tendency to 

 increase the weight of the barium sulphate precipitate. 



A new method for the rapid determination of phosphoric acid in alkaline 

 phosphates, M. E. Pozzi-Escot {Bui. Assoc. Chim. Sucr. ct Distill., 26 {1909), 

 No. 12, pp. 1162, 1163). — The method is a volumetric one and consists in taking 

 10 cc. of the phosphorus solution, adding 2 drops of a 0.2 i)er cent solution of 

 heliauthiue and 5 drops of a 1 per cent solution of phenolphthalein, and then 

 just so much dilute sulphuric acid as will give the solution a reddish tint. 

 The color of the solution is brought back to yellow, which is the neutral point of 

 the helianthine, by the addition of soda solution, and then titrated with tenth- 

 normal alkaline solution until the pink tint is obtained. Each cubic centimeter 

 of the tenth-normal alkaline solution employed is equivalent to 0.0071 gm. 

 phosphoric acid. 



Moisture discrepancies in phosphate rock of the Pacific, C. C. James {Jour. 

 Indus, and Engin. Chem., 1 {1909), No. 9, pp. 657-659). — Phosphate rock when 

 ground for analysis shows a perceptible loss in moisture. Tests were made to 

 demonstrate this. Stress is laid upon the proper selection of representative 

 samples. 



Limitations of starch as an accelerator, C. K. Francis {Jour. Indus, and 

 Engin. Chem., 1 {1909), No. 9, pp. 678, 679). — In a soil analysis it was found 

 that the blank containing starch and sodium peroxid gave the same percent- 

 ages of phosphorus as some of the soil samples. An examination of several 

 samples of starch revealed a phosphoric acid content, ranging between 0.169 

 and 0.0.S6 per cent. The author has substituted sugar for starch in this work. 



The determination of phosphoric acid in metabolism experiments by the 

 Neumann method, H. Schaumann (Ztschr. Analyt. Chem., ^8 {1909), No. 10, pp. 

 612-617, figs. 3). — A description of Neumann's method as employed by the 

 author in metabolism work is given. The filtering apparatus used is shown. 



The determination of phosphorus in flesh, P. F. Trowbridge {Jour. Indus, 

 and Engin. Chem., 1 {1909), No. 9, pp. 675, 676).— With 72 samples of flesh the 

 percentage of phosphorus by ashing was 0.0028 higher on an average than that 

 obtained by digestion with sulphuric acid. 



Handbook of biochemical methods, E. Abderhalden {Handbuch der bio- 

 chemischen Arbcitsmethodcn. Berlin and Vienna [1909], vol. 1, pt. 1; rev. in 

 18556—10 2 



