AGRICULTURAL CHEMISTRY — AGROTECHNY. 613 



(1914), ^0. 91, Rcfcratenteil, p. 625). — The methods worked out can be divided 

 into three groups: (1) A modification of the Gayon and Dubourg metliod ; (2) 

 separation of niannit compounds of definite composition, when appropriate com- 

 pounds can be obtained with Ijetones and aldeliydes ; and (3) indirect methods 

 which do not involve the separation of mannit. 



Determination of the amino acid and polypeptid nitrog-en in barley, malt, 

 and beer by the formaldehyde titration method, L. Adleb (Ztschr. Oesam. 

 Brauic, 37 (1914), Nos. 9, pp. 105-108, fig. 1; 10, pp. 117-121; U, pp. 129-133).— 

 The method described is based on principles similar to those set down by 

 Sorensen et al. (E. S. R., 19, p. 808; 23, p. 217). Phenolphthalein was used 

 as an indicator. See also a note by Schjerning (E. S. R., 32, p. 23). 



The presence of citric acid in nntural wines, Blarez. Denig£s, and Gayon 

 (Ann. Falsi/., 7 (1914), No. 63, pp. 9-11).— Certain countries do not admit wines 

 which contain citric acid, and this study was made for the purpose of de- 

 termining whether French wines, especially Sauternes, contain this acid 

 naturally. The method used in the investigation was Denig6s. 



In 25 wines made in the years 1893, 1903, 1906, 1907, 1908, and 1912 the 

 percentage varied from 0.01 to 0.045. Wines taken from Montbazillac, Anjou, 

 and on the Rhine (1904 to 1911, 13 samples) contained from 0.005 to 0.03 per 

 cent. The juices of 16 samples of red and white grapes were found to contain, 

 before fermentation, from 0.012 to 0.05 per cent and after fermentation, from 

 0.008 to 0.05 per cent. 



Analysis of milk, G. MeillSre (Jour. Pharm. et Chim., 7. scr., 9 (1914), Nos. 

 10, pp. 489-493; 11, pp. 559-563, fig. 1). — ^After discussing in a general way the 

 physical methods for density, freezing point, and electrical coaductivity, the 

 methods for making quantitative determinations of the components of milk, 

 especialy fat, are considered. A modification of Armand Adam's /uethod, which 

 allows the determination of fat, dry matter, lactose, and casein, but not the 

 salts, in the same sample, is proposed. This requires two hours at the longest 

 for making a chemical examination of milk without special apparatus. It 

 separates the milk by means of a mixture consisting of 1,000 cc. of 75 per cent 

 alcohol and 1,100 cc. of ether into a layer of fat and a layer of nonfatty sub- 

 stances. Ammonia is added in sufficient quantity to insure a good separation 

 of liquids. The ethereal layer is drawn off and evaporated on the water bath. 



The specific weight of milk serum in the detection of water adulteration, 

 Herramhof (Molk. Ztg. [Hildesheiin], 28 (1914), No. 7, pp. 115-118).— It was 

 found that the specific weight of milk serum from different cows shows less 

 variation than does that of the entire milk, that it is corre.spondingly lowered 

 as the water content increases, and that it remains unchanged after three days' 

 coagulation. It is stated that clouded milk serum may be made clear by filtering 

 through bone charcoal. 



Lime-sulphur sprays, their composition and analysis, A. A. Ramsay (Jour, 

 Agr. Sci. [Etwland], 6 (1914), No. 4, PP- 476-483).— In a previous paper (E. S. R., 

 31, p. 541) it was stated that the monosulphid sulphur present in lime-sulphur 

 sprays appears to be essentially calcium hydroxy hydrosulphid (CaHSOH) 

 with very minute quantities as calcium hydrosulphid (CaH2S2). "The solu- 

 tion of lime sulphur then appears to consist of calcium hydroxyhydrosulphid, 

 calcium thiosulphate, calcium sulphate with sulphur held in solution." This is 

 now amended by adding calcium disulphid. 



The method of analysis is now as follows : Dilute 50 cc. of the concentrated 

 lime sulphur to 500 cc. with water. (1) Titrate 25 cc. of the diluted mixture 

 with decinormal iodin solution till the yellow color is discharged. The num- 

 ber of cubic centimeters used multiplied by 0.0016=sulphur by 0.0028=lime. 



