RECENT WORK IN AGRICULTURAL SCIENCE. 



CHEMISTRY. 



Comparison of methods of sugar analysis as applied to grape 

 juice (musts), Gr. PI Colby {California Sta. Ept. liiO:-> and 1894, 2>P- 

 326,327). — A coniparisou is given ou 3 samj^les of grape juice of the 

 voUimetric and gravimetric methods described in the Proceedings of 

 the Association of Official Agricultural Chemists for 1892.^ The results 

 by the volumetric method and the electrolytic gravimetric method 

 agreed quite closely, but the method of reducing the cuprous oxid in 

 hydrogen gave results somewhat higher. 



The unreliability of the Kjeldahl method for determining nitrogen in chloro- 

 platinates, Dklkpixk (Bid. Soc. Chim. Pariti, lS-14 {1S'9J), A"'o. 4, p. £.<j).— TriaLs of 

 this method ou chloroplatiiuite of triiiiethj'Iainin gave results iu uo way approach- 

 ing the theoretical percentages of nitrogen. This was due to the escape of free 

 nitrogen. 



Researches on the separation of free hydrochloric acid from chlorids, espe- 

 cially in analysis of the gastric juice, H. LKSCffiUR (Bid. Soc. Cliim. Paris, 13-14 

 {1S95), No. 3, pp. l4j-l.',r>,f.g. 1). 



The transformation of starch into sugar, Duclaux {Ann. Inst. Pasteur, 9 (1895), 

 No. 1, pp. 56-64). — A critical review. 



Rapid determination of starch, P. L. Hibisard (Nene Zlschr. EUhenz. Ind., S4 

 {1895), No. 7, pp. Si:.S7). 



The action of ammonia iipon dextrose, W. E. Stone {Amo: Chem. Jour., 17 

 {1895), No. 3, pp. 191-r.tH). 



The carbohydrates of the gum of Acacia decurrens, W. E. Stoxe {Amer. 

 Chem. Jour., 17 {1S95), No. 3, pp. 196-199). — This gum " does not esseutially differ from 

 gum arabic or peach gum or cherrj^ gum. It furnishes an additional example of the 

 occurrence of a galacto-araljau complex." 



On the composition and analysis of brandy, X. Rocqu]:s {Compi. Rend., 120 

 {1895), No. 7, pp. 372-374). 



The oxidation of tannin in cider, L. Lixdet {Compt. Bend., 120 {1895), No. 7, 

 pp. 370-372). — It is claimed, as pointed out by Bertrand {Compt. Rend., 120 {1895), No. 

 5, p. 266), that the brown coloration of the cider and marc is due to the energetic 

 oxidation of the tannin ])resent by a fernunt similar to diastase which is designated 

 laccasc. 



The determination of tannin in wines, A. Vigxa {Staz. Sjyer. Agr. Hal., 28 {1895), 

 No. 1, pp. 19-22). 



On the analysis of tannin compounds, A. (tIkard {Compt. Rend., 120 {1895), 

 No. 7, pp. 358-360). — The discordant results obtained by different chemists with the 

 author's method {Compt. Rend., 95 {1892), p. 185), are explained by variations iu the 

 character of the intestinal membrane used. The difficulty is removed by carefully 

 purifyiug the membrane. 



lU. S. Dept. Agr., Div. of Chem. Bill. 35 (E. S. II., 4, p. 580). 



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