304 EXPERIMENT STATION RECORD. 



ceiitrations (loss than 1/200 uioleculo for the usual magnesia mixture or less 

 than 1/50 molecule when much anunonia salt is used) a qualitative separation 

 can be had, but on the other hand the dilution must not be carried so far as 

 to get beyond the detection point of the arsenic ion. 



The carbonates of copper and the cupricarbonates, S. IT. Pickering (Jour. 

 Chcm. Soc. [London], .9,7 (190!)), No. 562, pp. U09-l-',29, chart i).— This work 

 has some reference to the copper compounds as they might exist in Bordeaux 

 mixture. 



Phenolphthalein as a reagent for hydrocyanic acid, P. Dobriner and A. 

 Oswald (Zt.schr. Annli/t. Client., .',8 {1909), No. 11, pp. 109, 7i0).— By adding 

 to hydrocyanic acid Ji few drops of an alkaline hydroxid phenolphthalein solution, 

 and then coiiper sulphate solution (1: 2,000) a red coloration is obtained, which 

 is due to the oxidation of the phenolphthalein. It is sensitive to 1 : 500,000. 

 Paper impregnated with phenolphthalein copper solution is also colored red by 

 hydrocyanic acid. 



A characteristic reaction for free tartaric acid, A. Tagliarini {Bol. Chim. 

 Farm., 46 (1907). pp. 49S-Jf95 ; abs. in Ztschr. Untersuch. Nalir. u. Genussmtl.. 

 18 (1909), No. 8, p. JfTO). — The author reports that the reaction proposed by 

 Ganassiui for tartaric acid can also be obtained with oxalic and citric acids, but 

 not with formic, acetic, and succinic acids. 



Formaldehyde, J. E. Orloff, trans, by C. Kietaibl (Forinaldehyd. Leipsic, 

 1909, pp. VIII-\-327, pis. 3, figs. 9). — This is a comprehensive volume of most of 

 the important facts pertaining to formaldehyde, and includes the various 

 processes of production, the reactions for formaldehyde, its uses, analyses, the 

 conversion of methyl alcohol into formaldehyde, the new condensation products 

 of formaldehyde, the pyrogenetic contact reactions, and the methods for the 

 detection of formaldehyde. 



[Methods of analysis of fertilizers and feeding stuffs for 1908 by the 

 Board of Agriculture and Fisheries] (Analyst, 34 (1909), No. 403, pp. 461- 

 468). — This is a description of the methods of analysis of fertilizers and feed- 

 ing stuffs agreed upon by the Board of Agriculture and Fisheries. 



Note on a rapid method of analysis of waters, L. Marcotte (Ann. Observ. 

 Munic. (Observ. Montsouris) [Paris], 9 (1908), No. 3-4. pp. 339, 340).— A quick 

 fermentation method is described. 



The determination of chlorid of magnesium in water, H. Emde and R. 

 Senst (Ztschr. Angnr. Vlicni., 22 (1909), No. ',2, pp. 2038-2040).— The: authors 

 find that Pfeiffer's method for determining magnesium chlorid by noting the 

 content of chlorin in the water before and after incineration of the ash does not 

 give satisfactory results, and conclude that the only way to obtain correct re- 

 sults is to make the usual analysis. 



[The determination of chlorid of magnesium in water], Pfeiffer (Ztschr. 

 Angrir. Chrm.. 22 ( 1909). No. ',2. p. 20)0). —\ reply to the above. 



The determination of magnesium chlorid in water, H. Emde and 1\. Senst 

 (Ztschr. Angciv. Chcm., 22 (1909), No. 46. pp. 2236-2238) .—A reply to Pfeiffer 

 (see above), with some tests to prove the authors' former conclusions. 



The interpretation of chemical water analysis, H. Klut, trans, by E. A. 

 Gieseler (Engin.. Rec, 60 (1909), No. 18, pp. 498-500). — This is a translation 

 of an article already noted from another source (E. S. R., 21, p. 521). 



Colorimetric method for the determination of molecular weights of car- 

 bohydrates (starch, glycogen, dextrins), L. Wacker (Bcr. Dent. Chem. 

 Gesell., 42 (1909), No. 12, pp. 2675-2680; abs. in Jour. 8oc. Chcm. Indus., 28 

 (1909), No. 16, p. 898). — The basis of the method is the coloration produced by 

 an alkaline solution of phenylhydrazinsulphonic acid, this being constant for 

 equimolecular concentrations of various carbohydrates. The color standards 



