512 EXPERIMENT STATION RECORD. 



Progress in systematic qualitative organic analysis, S. P. Mxtlliken (Jour. 

 Amer. Chem. Soc, 32 {1910), No. 9, pp. 10^9-1057). — A discussion as to the 

 value of various methods of classifying organic substances for identification. 



Researches in regard to the precipitins of honey, B. Galli-Valeeio and M. 

 BoRNAND {Ztschr. Immunitatsf. u. Expt. Ther., I, Orig., 7 {1910), No. 3, pp. 

 331-341 ) . — The results show that by injecting the protein of honey from various 

 sources into rabbits a serum could be obtained which was specific for the honey 

 from which the protein was derived. The method is of particular value for 

 detecting adulteration with artificial honey. 



Detection of invert sugar in commercial honey, H. Quantin {Ann. Chim. 

 Analyt., 15 {1910), No. 8, pp. 299-301).— From this work the author concludes 

 that the presence of the furfurol reaction in honey prepared by expression but 

 without heat always indicates an adulteration. On the other hand, the presence 

 of the furfurol reaction in honey extracted by heat does not indicate adulter- 

 ation with certainty because the possibility exists of the production of furfurol 

 during the heating process. 



The use of the refractometer in the analysis of jams and jellies, marma- 

 lades and confections, W. Clacher {Internat. Sugar Jour., 12 {1910), No. 

 U2, pp. 509-520).— The method is as follows: 



" Two gm. of the finely powdered sweet are weighed in a dry neckless stop- 

 pered weighing bottle 20 to 40 cc. capacity ; 2 cc. of hot water are added and 

 the sweet digested for a few minutes. Then the bottle with contents is cooled 

 to 20° C, water added to make exactly 4 gm. of water and sweet, the emulsion 

 shaken, and a portion transferred to another small dry stoppered weighing 

 bottle for future reading with the refractometer ; the bottle with the remanider 

 of the emulsion is weighed, and to it added water at 20° to make the amount of 

 water added to 1 gm. of sweetmeat of 5 gm. weight. The refractometric read- 

 ings of these solutions are then read at 20° and from these the percentage sugars 

 is calculated from the tables," which are given. 



The estimation of small quantities of essential oil in spices, etc., J. A. 

 Brown {Anali/st, 35 {1910), No. J,]-'t, pp. 392-396, fig. 2).— This method is based 

 upon the same principle as the method for total volatile matter, previously de- 

 scribed (E. S. R., 22, p. 513), with the exception that the gaseous products are 

 conducted through an ordinary heated combustion tube containing copper oxid, 

 and the carbon dioxid and water which are formed are collected and weighed. 

 The volatile carbon was found to have a sufiiciently close relation to the amount 

 of volatile oil present. 



A method for the detennination of tin in canned foods, H. Schreiber and 

 W. C. Taber {U. 8. Dept. Agr., Bur. Chcm. Circ. 67, pp. 9). — As the various 

 methods, with the exception of Schryver's (E. S. R., 20, p. 11.55), heretofore 

 proposed for estimating the tin in canned foods yielded nonconcordant results, the 

 authors elaborated an alkali fusion method for which the following advantages 

 over the Schryver wet method are claimed: "(1) It decreases the errors of 

 sampling; (2) it decreases the errors due to multiplication when calculating 

 to milligrams per kilogram; (3) there need be no loss of samples if the mate- 

 rial is properly ground and not heated too rapidly on the hot plate; (4) in the 

 wet ashing methods it is necessary to neutralize a large amount of acid before 

 precipitating with hydrogen sulphid." 



The proposed method is conducted as follows : Weigh out 100 gm. of the 

 sample with 10 gm. of magnesium oxid into an 8-oz. wrought-iron crucible, add 

 50 cc. of an alkaline solution containing 150 gm. of sodium hydrate and 100 

 gm. of sodium carbonate per liter, stir well, add 75 cc. of 95 per cent alcohol, 

 and stir again. Then place on a steam bath, and apply a gentle gradual heat 



