410 EXPERIMENT STATION EECORD. 



sition of these clays bears no relation to the chemical composition of kaolin, 

 because much of It consists of quartz particles. The claim made for the uni- 

 formity of these products obtained by this method Is, therefore, not justified. 



In regard to a precipitin with which it is possible to differentiate boiled 

 insoluble protein, W. A. Schmidt (Ztschr. Immunitdtsf. ti. Expt. Ther., I, Orig., 

 13 (1912), No. 2, pp. 166-185). — Blood serum heated for 30 minutes at a tem- 

 perature of 70° C, then treated with dilute sodium hydrate, and heated for 

 15 to 20 minutes more in order to make it nonreacting to either native or heat 

 precipitin, when injected into an animal will yield a serum which contains 

 a heat-alkaliue-protein precipitin. This serum will react with a serum which 

 has been boiled for 3 hours and dissolved in a decinormal sodium hydrate solu- 

 tion. The serum is a positive test for differentiating insoluble proteins. 



In regard to the utility of the ester method for detecting monoaniino acids 

 when polypeptids are present, E. Abderhalden and R. Hanslian (Iloppe- 

 Seyler's Ztschr^ Physiol. Chem., 77 {1912), No. 4, pp. 285-288) .—The method is 

 deemed perfectly reliable for this purpose, providing the necessary precautions 

 are taken. 



A comparative study of some analytic methods for determining phos- 

 phorus in vegetable products, A. Ponte (Staz-. Sper. Agr. Ital., J/Jf (1191). No. 

 5-6, pp. 459-.'i61). — Comparing the results obtained for phosphorus when incin- 

 erating by the oi-dinary ashing and the electrical methods (E. S. R., 20, p. 

 207), it is noted that the former has losses which vary between 2 and 11 per 

 cent. The methods which incinerate in the presence of calcium oxid yield figures 

 about similar to those obtained with the electrical method. 



The ash of vinegar, R. E. Remington (North Dakota Sta. Spec. Bui., 2 

 (1912), No. 5, pp. 92-9. )). — In determining the phosphoric acid content of vine- 

 gar considerable difficulty was always experienced in obtaining duplicate re- 

 sults for the soluble and insoluble portion, although concordant results for total 

 phosphoric acid were practically always obtained. In order to determine if the 

 method of ashing used was accountable for these variations, 3 samples of 

 cider vinegar were ashed in platinum dishes over Bunsen burners, which in each 

 ease wore adjusted to give various degrees of heat. Some of the samples were 

 finished with a blast lamp. 



" While the temperature seems to exert little or no influence upon the total 

 amount of phosphoric acid recovered, in all cases the soluble portion increases 

 with increasing temperature. Expecting that higher temperature would favor 

 the formation of more or less insoluble pyrophosphates, the results obtained are 

 surprising. The alkalinity of the soluble ash increases with the temperature 

 so long as it does not rise above the fusing point of the ash. But when the 

 blast lamp was used, a decrease in alkalinity was noted, due to the loss of po- 

 tassium salts by volatilization. That this is so was shown by ashing dupHcate 

 portions of vinegar, in one case blasting only long enough to obtain complete 

 fusion, in the other for 30 minutes. ... If the ash data are to continue of 

 value in the interpretation of vinegar analysis, the ashing must be done under 

 more carefully specified conditions than heretofore — say in an electric muffle, 

 with accurate temperature control and for a definite time. Otherwise no two 

 chemists can expect to obtain concordant results." 



The Fiehe reaction for the examination of honey, L. Stcecklin (Ann 

 Falsif., 5 (1912), No. .',1, pp. 116-121). — ^This is a discussion of the reasons for 

 some of the failures obtained with the Fiehe reaction, and a description of a 

 procedure which will give better results. 



The occurrence of boric acid in honey, (i. BiJTTNER (Ztschr. Untersuch. Nahr. 

 V. aenussmtl., 23 (1912), No. 4, pp. 139, J^O).— Pure honey often contains boric 

 acid. 



