AGRICULTURAL CHEMISTRY. 305 



study of niothods from which geiun-al conclusions nro drawn rcf^ardins tho de- 

 It'rniination of orpniic acids in wine. 



The estimation of succinic acid in wine, C. von df.r Heidi: and II. Steiner 

 (Ztschr. Untcrsuch. Niihr. n. (Jnuissmtl, 11 {1909), No. (!, pp. 291-307).— A 

 critical study of methods. The authors state that they i)urpose continuing 

 studies of the formation of succinic acid in fermenting musts. 



The volumetric determination of sulphuric acid in wine, C. Blarez and 

 L. CiiELLE (Bid. Assoc. Cliiiii. Sucr. ct Distill., 26 (1909), No. 8, pp. 690-693).— 

 Tho method described is preferred by the authors to the gravimetric method, as 

 they consider it quicker and just as reliable. 



Determination of tartaric acid in wines, Mestrezat {Jour. Pharm. et Chim., 

 6. so:, 29 (1909). No. 1, pp. 9-1,',; abs. in Analyst, S'f {1909), No. 396, p. 10.^).— 

 The author has obtained better results with the evaporation methods than with 

 the precipitation methods. A metliod is described in which duplicate analyses 

 are concordant to 0.5 i;er cent and in which the presence of'malic acid, succinic 

 acid, and sugar has been proved to be without influence on the result. 



Studies on stout, N. Van Laer and J. D. Wilson {Wchnschr. Bran., 26 

 {1909), No. 1, pp. 6-9; ahs. in Jour. Soc. Chem. Indus., 28 {1909), No. 3, p. 

 1.^)5). — The authors have found lactic-acid bacteria in stout, but they differ 

 from those found in milk, as they soon die in the presence of the acid which 

 they have produced. 



Progress in the chemistry of fermentation industries for the year 1908, 

 O. MoiiR {Ztschr. Angcic. Vlicni., 22 {1909). Nos. 77/, pp. 625-630; 15, pp. 61',- 

 616). — This is a digest of the literature on the subject. 



Contribution to the judging of milk by means of the refractive power of 

 milk serum, T. Henkel {Moll;. Ztg. Berlin, IS {1908), No. 52, pp. 613-616; abs. 

 in Milclnc. Zentbl., 5 (1909), No. 3, pp. 131, 132). — The author deiermined tha 

 refractive power of 2,093 samples of milk serum. There appear to be many 

 factors which influence the result, but as a rule the refractive power is a correct 

 indication of the amount of solids-not-fat. 



Comparison of some methods of determining the fat content of milk, 

 A. Stein {Milchic. Zentbl., 5 {1909), No. 5, pp. 209-211). — The average percent- 

 age of fat in 34 samples of raw milk as determined by the Gerber method was 

 3.636, by the Liebermann-Szekely method 3.5SS. and by the Soxhlet method 

 3.509. In milk preserved with formaldehyde the corresponding figures were 

 3.649. 3.597, and 3.491 jier cent, resjiectivc-ly. 



The determination of the fat content of milk by the Rose-Gottlieb method, 

 C. HuYGE {Rev. Gen. Lait, 1 {1909), No. 12, pp. 265-212).— Thv author found 

 that in determining the percentage of milk fat by this method the upper layers 

 of the ether- fat solution were richer in fat than the lower layers. 



The determination of milk fat and coconut fat, M. Monhaupt {Chem. Ztg., 

 33 {1900), No. 3J,, pp. 305, 306; abs. in Analyst, 3', {1909), No. 398, p. 212).— The 

 author made a comparison of the Kirschner method of separating the volatile 

 insoluble fatty acids with the Reichert-Meissl and Polenske values, and thinks 

 that the Kirschner and the new Keichert-Meissl values promise to be of great 

 service in testing butter mixtures. 



Calorimetric constant of Argentina butter, E. II. and L. H. Duci.oux {Rev. 

 Facult. Agron. y \ et. La Plata, 2. ser., 5 (1909), pp. 93-105, map /).— The heaf 

 of combustion of a number of samples of butter was determined and compared 

 with other constants. As a result of their investigations the authors cimclude 

 that the heat of combustion is a constant which is of value for the judging of 

 the purity of butter. 



On the application of the Gottlieb method for the determination of fat in 

 cheese, A. G. Palmquist {Svensk Kern. Tidskr., 21 (1909), No. .',, pp. 92-95).— 



