AGRICULTURAL CHEMISTRY. 913 



the determination of tlio value of raw materials and jirodncts in stareh making 

 and in the distilling industry. 



Determining' the starch, in barley by means of polarization, Windisch 

 (Ztscfir. Spiritusimlus., 30 (1907), Nos. 35, p. 319; 36, p. 391). — A summary 

 and discussion of data and a comparison of methods. 



Note on the estimation of starch in commercial starch and starchy ma- 

 terials, E. Parow and F. Neumann (Zischr. Spirit imndus., 30 (1907), No. 

 .'*,?, pp. 563, 56.'f). — From a comparative study of methods, the authors suggest 

 the use of a sodiuni-chlorid-liydrocliloric acid solution as a solvent. 



Composition of cacao crude fiber, H. Matthes and F. Streitbekger (Ber. 

 Dent. Chem. Gcsell., J,0 {1907), pp. Jil95-4199; abs. in Vhriii. Zrnthl., 1907, 

 II, No. 22, pp. 1806, 1807).— A critical study of methods. 



A comparison of methods for the determination of the alkalinity of ash. 

 H. C. Lythgoe {A)iii. Rpt. Bd. Health Mass., 38 (1906), pp. .',//-///.'/).— The 

 incinerated ash was extracted successively with cold and boiling water and the 

 extract titrated with decinormal sulphuric acid, using plienolphthalein, methyl 

 orange, cochineal, and litmus as indicators. With phenoli)hthalein an excess 

 of acid was added, the solution boiled until the carbon dioxid was expelled, 

 and the excess of acid determined by titrating with decinormal alkali. Vinegar, 

 lime juice, and raspberry sirup were the materials used. From this work, 

 which is regarded as preliminary, the author concludes that phenol phthalein 

 gives more nearly the correct results. 



New method of separating and determining organic acid in fruits and 

 vegetables, J. M. Alisahary (Voinpt. Rend. Acad. Sci. [Pans], lJf5 (1907), 

 No. 22, pp. 1232, 1233). — Since the direct analysis of plant extracts with water 

 is time-consuming and unsatisfactory, the author extracts successively with 

 chloroform, alcohol, and ether. The free organic acids are recovered in the 

 ethereal and alcoholic extracts. In order to recover the acids present as salts 

 the material is boiled before extraction with alcohol containing hydrochloric 

 acid. 



The determination of tartaric acid in the presence of malic and succinic 

 acids, J. VON Ferentzy {Chem. Ztg.. 31 {1907), No. 90, p. 1118). — A brief note 

 on the determination of tartaric acid as a basic magnesium salt, a method, 

 which, according to the author, gave satisfactory results. 



The determination of tartaric acid in cider, G. A. Le Roy {Compt. Rend. 

 Acad. 8ci. [Paris], 145 {1907), No. 25, p. 1285).— The method outlined depends 

 upon the color reaction between a solution of resorcin and sulphuric acid. 



A method of determining alcohol in wine, M. Duboux and P. Dutoit 

 {Schwciz. Wchnschr. Chem. u. Pharm., //5 {1907), Nos. 48, pp. 753-755; .',9, 

 pp. 773, 77^). — The critical temperature method in which variations are brought 

 about by the proportion of water present. As shown by comparative determina- 

 tions the values obtained agree closely with those by the specific gravity method. 



Benzoic v. cinnamic acid in food analysis, W. L. Scoville {Amer. Jour. 

 Pharm., 79 {1907), No. 12. pp. .5 '/.''-J.T /).— According to the author's experi- 

 ments, it is difficult to differentiate between cinnamic and benzoic acid by 

 the ordinary analytical methods, a matter which is of importance in the analy- 

 sis of goods spiced with cinnamon. 



"The best test found for distinguishing between the two acids is the man- 

 ganous test. Manganous salts give a white precipitate with clnnamates, which 

 gradually becomes crystalline. No precipitate is found with benzoates, even 

 in moderately strong solutions. The precipitate forms slowly with cinnamates, 

 but is quite delicate. The solution should be allowed to stand an hour, at 

 least, with moderately weak solutions." 



