AGRICULTURAL CHEMISTRY — AGROTECHNY. 13 



Estimation of phosphoric acid in cidei's and vinegars, F. F. Hasbbouck 

 (Pure Products, (J (PJJO), No. JO, iip. oS3~o8o). — The author describes a com- 

 posite volumetric method, in which either acid and alliali or ammonia and 

 potassium pormaneauate are employed as the titratiuf^ agents. 



Honey fermentation and some notes in regard to the chemical composi- 

 tion of honey, T. Nussbaumeb (Ztschr. Untersuch. Nahr. u. Genussmtl., 20 

 (JUJO), Xo. J, i)p. 272-277). — The author found several species of zj-gosaccharo- 

 mycetes in numerous samples of honeys and from different sources, the origin of 

 which could not be determined. Natural honeys did not generally give the 

 Fiehe reaction. Foreign honeys gave a lesser pi'otein precipitate (Lund) than 

 European honeys. 



Identification test for caramel, G. II. P. Lichthardt (Jour. Indus, and 

 Engin. Chcm., 2 (1010), No. 9, p. 389).— The following reagent for detecting 

 caramel in vinegars, liquor, and flavoring extracts has given good results in 

 the hands of the author: Tannic acid 1 gm., sulphuric acid (specific gravity 

 1.84) 0.75 gm., and enough water to make 50 gm. 



Saffron and its adulteration, E. Collin (Ann. Falsif., 3 (1910), No. 23, pp. 

 3'j3'-3(j'.), fif/fi. JJf). — This article describes the usual microscopical appearance of 

 saffron and discusses the normal and abnormal impurities in the commercial 

 article. 



Distilled liquors: Whisky (rye, Bourbon, and Scotch), brandy (cognac), 

 and gin, W. O. Holmes (Philippine Jour. Sci., A. Chem. and Geol. Sci., 5 

 (19 JO), No. 1, pp. 23-28). — A study of methods, with some recommendations, 

 and analyses of distilled liquors which entered the port of Manila. 



The bitter acid content of Hungarian hops, G. Bir6 (KisC'rIet Kozlem., 13 

 (1910), No. .'i, pp. .'il9-.i27). — The author examined 33 samples of Hungarian 

 hops and found the average bitter acid content to be 3.38 per cent, the maximum 

 4.89 per cent, and the minimum 1.70 per cent. 



The sources of error in the Folin method for the estimation of creatinin, 

 A. E. Taylos (Jour. Biol. Chcm., 9 (J Oil), No. 1, pp. 19, 20). — Among the sources 

 of error in this method (E. S. R., 17, p. 165) pointed out by this author are 

 the range of concentration (5 to 15 mg. in the volume to be tested), the varying 

 intensity and quantity of normal and abnormal urinary pigments, dilution in 

 its relation to the amount of picric acid employed, the eye in the absence of 

 standardized light, and the kind of light used. " Under ideal conditions, the 

 method will enable one to estimate 10 mg. of creatinin with an accuracy of plus 

 or minus 0.1 mg." 



A modified guaiac test with sodium peroxid, B. Bakdach and S. Silbeb- 

 STEiN (Ztschr. Physiol. Chem., 65 (1910), No. 5-6, pp. 511, 512; ahs. in Zentbl. 

 Biochcm. u. Biophys., 10 (1910), No. 9-10, p. 462). — The test is carried out as 

 follows : 



To 5 cc. of the fluid to be examined add a freshly prepared alcoholic solution 

 of guaiac dropwise until the fluid begins to become opaque, and then a knife 

 point of sodium peroxid, following quickly with 2 cc. of a 30 per cent acetic 

 acid solution, and covering the mixture with a layer of alcohol. Even when small 

 traces of the blood or other reacting substance are present a blue ring is 

 obtained. 



The chemical processes involved in the coagulation of milk by rennet, 

 I. Bang (Skand. Arch. Physiol., 25 (1911), No. 1-3, pp. i05-i 7/4). —The results 

 of these extensive experiments show that the processes involved in the coagula- 

 tion of milk are exceedingly complex. 



In the case of the calcium salts it could be noted that these are distributed 

 among the organic and inorganic acids, lactalbumin, lactglobulin, and casein. • 



