METEOROLOGY WATER. 509 



hydrochloric acid. During the first 2 minutes the suction must be conducted 

 cautiously, because strong suction is required for the succeeding 8 minutes. 



The solution containing the absorbed ammonia is diluted to about 60 cc., to 

 which is added 5 cc. of diluted Nessler solution (5 cc. plus 25 cc. of water). 

 As a control a solution containing 1 mg. of pure ammonium sulphate in about 

 60 cc. of water and contained in a Nessler tube is used. Both solutions are 

 then filled up to the 100-cc. mark and compared in a Duboscq colorimeter. The 

 ammonia can also be determined by titration, using alizarin red as an indicator. 



The distribution of amyg'dalin, L. Rosenthaler (Ar-ch. Pharm., 250 (1912), 

 pp. 298-301). — For the purpose of finding out whether amygdalin from various 

 sources (apricot, peach, plum, cherry, apple, and quince) was stereo-isomeric, 

 the melting point, specific rotation, molecular weight, percentage of nitrogen, 

 and the rotation of the mandelic acid obtained by hydrolysis of the amygdalin 

 were determined. They were found identical with the amygdalin obtained 

 from the bitter almond. 



It is also pointed out that in Bourquelot's method the changes produced by 

 emulsin are noted with the polariscope after clearing the solution with lead 

 subacetate. It is claimed that correct results can only be obtained with such 

 a method when the emulsin solution has been rendered optically inactive by 

 the clarification process. This was found not to be the case with the emulsin 

 solutions clarified with the lead subacetate process, and a left-hand rotation 

 was obtained. 



Choice of yeasts in the biochemical detection of sugars and glucosids, 

 E. BouRQUELOT and H. Herissey (Jour. Pharm. et Chim., 7. ser., 6 {1912), No. 

 6, pp. 2Jt6-253; al)S. in Jour. Chem. Soc. [London], 102 (1912), No. 601, II, p. 

 llO-'i). — In reply to the abstract above, it is pointed out that the enzym which 

 attacks amygdalin and produces mandelonitrile glucosid is amygdalase and not 

 invertase. The second factor mentioned by Rosenthaler, that emulsin prepara- 

 tions are often levorotatory, has not been noted, but if such is the case, allow- 

 ance can easily be made for it in the calculation. 



In reg-ard to the technical-scientific work in potato drying', E. Parow 

 (Ahs. in Ztschr. Angeio. Chem., 25 (1912), No. 16, pp. 777-779).— This is & sum- 

 mary of the work conducted in the laboratories of the Society of German Potato 

 Driers. It includes reports on the comparative analyses of potato chips, flakes, 

 and meal, which show that there is only a little difference in their composition. 

 The results of some tests of machinery installed in potato-drying factories are 

 discussed, as well as some new drying apparatus and the yields. 



Conducting fermentation processes in breweries, distilleries and yeast 

 factories, M. Delbruck and F. Hayduck (Die Gdrungsfuhrung in Brauerei, 

 Brennerei und PrefshcfefabrUc. Berlin, 1911, pp. X+225, figs. 6). — This book 

 is based upon the work and results obtained at the Institute for the Fermenta- 

 tion Industi"y at Berlin, Germany. 



METEOaOLOGY— WATEU. 



Agricultural meteorological contributions (Trudy Selsk. Khoz. Met., 1912, 

 No. 10, pp. 11+173, figs. 5). — This number of the contributions from the 

 Meteorological Bureau of the Scientific Committee of the Ministry of Agricul- 

 ture of Russia contains, among others, the following articles (in the Russian 

 language) : The Dependence of the Yield of Oats on the More Important 

 Meteorological Conditions During 190S and 1909, by A. P. Chernyi; Meteoro- 

 logical Conditions Affecting the Growth of Oats, by M. A. Evstifeeva; and In- 

 structions for Carrying on Agricultural Meteorological Observations at Garden 

 and Tobacco Stations, by V. O. Askinazi. 



