AGRICULTURAL CHEMISTRY AGROTECHNY. 709 



used for pure alkali phosphates, yield I'esults which compare well with the usual 

 gravimetric method. 



Preparation of neutral ammonium citrate solutions by the conductivity 

 method, R. A. Hall {Jour. Indus, and Engin. CJiem., 3 {1911), No. 8, pp. 559- 

 563, figs. 2). — ^The results indicate that the conductivity method of preparing 

 neutral solutions is applicable to the preparation of exactly neutral ammonium 

 citrate solutions of such a density that they cau, after neutralization, be diluted 

 with distilled water and brought to a density of 1.00 at 20°, and this method is 

 recommended for adoption as an Official Method for use in fertilizer analysis, 

 A tub of water may be substituted for the regulated thermostat, but the latter 

 is deemed preferable, as there is then no necessity of the measurements being 

 carried out so quickly. 



Quantitative determination of iron, ammonia, and nitrous acid in water 

 with the Autenrieth-Koenigsberger colorimetric method, K StJPFLE {Arch, 

 llyg., 7'4 {1911), No. jj, pp. 176-lS.'f, figs. 6). — A description of what is repre- 

 sented to be an extraordinarily practical, physically correct colorimetric appa- 

 ratus, with the methods employed for determining the substances mentioned 

 above in water. 



The use of the ester method in metabolism studies, B. O. Pbibbam {Hoppe- 

 Seylcr's Ztschr. Physiol. Chem., 11 {1911), No. 5-6, pp. I,12-ftl8).—lxi order to 

 employ the esterification method in metabolism tests where a mixture of pro- 

 teins and amino acids are concerned, the experiment must be accompanied by 

 blank tests, otherwise the results obtained may lead to serious error. Glycocoll 

 ester is easily saponified, and when this amino acid is not entirely esterified it 

 can be easily missed if present in only small amounts. Proteins were also 

 found to be entirely cleaved in a solution of absolute alcohol by hydrochloric 

 acid. Partial cleavage is present after a short contact. 



The separation and quantitative determination of small amounts of 

 pyridin and ammonia, Delepine and Soknet (A&s. in Chem. Ztg., 35 {1911), 

 No. 95, p. 872; Analyst, 36 {1911), No. 7/27, p. 508 ) .—Ammonia may be separated 

 from pyridin by mercuric chlorid in the presence of sodium carbonate and 

 sodium hydrate. The ammonia is removed from the precipitate obtained with 

 sodium thiosulphate. The pyridin is distilled from the filtrate and weighed as 

 a gold chlorid salt or platinate. 



In regard to the quantitative determination of globulins by precipita- 

 tion with ammonium sulphate and the purification of globulins, H, Wieneb 

 {Hoppe-Scyler's Ztschr. Physiol. Chem., 7Jf {1911), No. 1, pp. 29-66) .—This is a 

 study of methods, with particular reference to the globulins present in blood 

 serum. 



Determination of carbohydrates by oxidation with the aid of potassium 

 permanganate in an alkaline solution, W. Geeifenhagen, J. Konig and A. 

 ScHOLL {Biochem. Ztschr., 35 {1911), No. 3-4, pp. 169-193) .—Yeirious carbo- 

 hydrates, polyhydric alcohols and their aldehydes and ketones, as well as poly- 

 saccharids, can be decomposed quantitatively into oxalic acid and carbon dioxid 

 with potassium permanganate and alkali. From the amount of oxygen utilized 

 for the oxidation process it is also possible to calculate the amount of substance 

 originally employed, providing the solution has been made acid after oxidizing 

 and a standardized solution of potassium permanganate used for the titration. 

 Formic acid could not be detected among the oxidation products. 



The substances considered in this investigation were saccharose, lactose, 

 maltose, glucose, fructose, galactose, raffinose, erythrit, glycol, glycerin, arabi- 

 nose, xylose, rice starch, cassava starch, maunit, and dulcit. 



The determination of lecithin, C. Viechow {Chem. Ztg., 35 {1911), No. 100, 

 pp. 913, 914). — A number of methods are described, including a modified one 



