506 EXPERIMENT STATION EECORD. 



added, and the mixture shaken again. After standing from 24 to 48 hours the 

 clear petroleum ether layer is removed, the solvent dispelled by distillation, and 

 the residue dried at 100° C. 



Determination of unsaponifiable matter in oils and fats, H. Salomon (Ber. 

 Deut. Pharm. Gesell., 24 {19U), No. 3, pp. 189-193).— It is stated that the 

 modification of the Marcusson and Schilling method proposed by Klostermann 

 can be extended so as to allow at the same time the estimation of unsaponi- 

 fiable matter. 



From 50 to 100 gm. of oil or fat is saponified with alcoholic potash solution 

 and the resulting soap dissolved in water, extracted with ether, and after dis- 

 pelling the ether from the extract drying and weighing the residue. The crude 

 phytosterol is dissolved in hot alcohol and precipitated with an excess of digi- 

 tonin solution, 1 gm. of crystalline digitonin being required for each 0.4 gm. of 

 unsaponifiable matter. The precipitate resulting is collected, acetylated, and 

 the phytosterol acetate recrystallized according to the Klostermann procedure. 

 The unsaponifiable material in the filtrate can be determined by adding water, 

 extracting with ether, and weighing the ether extract after removing the ether. 

 Some tabulated results are given. 



Rice oil and rice fat, J. Davidsohn (Seifenfabrikant, 34 {1914), PP- ns, 

 179; ahs. in Ztschr. Angew. Chem., 27 {1914), No. 66-69, Referatenteil, p. 518).— 

 The rice oil obtained from rice bran by extracting or pressing is a mixture of 

 solid and fluid substances. The portion of the substances solid at room tem- 

 perature melts at 24° C. Freshly ground bran yields an oil with only a small 

 amount of fatty acids, but when old contains a large amount of these acids. 

 Rice oil has a specific gravity of 0.8907 at 99°, a saponification number of 193.2, 

 and an iodin number of 96.4 according to Smethan or of 91.65 according to 

 Browne. On storage the oil separates into a compact fat and a supernatant 

 clear oil of dark-greenish color, which can be saponified very easily. Its value 

 for the manufacture of soap is pointed out. 



The estimation of hydrocyanic acid in feeding stuffs and its occurrence in 

 millet and guinea corn, J. R. Furlong {Analyst, 39 {1914), No. 463, pp. 430- 

 432; ahs. in Jour. Soc. Chem. Indus., 33 {1914), No. 21, p. 1069) .—According to 

 this method 100 gm. of the ground material under examination is placed in a 

 Soxhlet apparatus and extracted for three hours with 10 per cent alcohol. The 

 extract, after removing the alcohol by distillation, is distilled with 150 cc. of 

 10 per cent sulphuric acid, the distillate being collected in 5 cc. of 10 per cent 

 potassium hydroxid solution. At the end of one hour the receiver is changed, 

 water added to the distillation flask, and the distillation continued. This opera- 

 tion is repeated until no more hydrocyanic acid is evolved. 



" The distillate is concentrated to 15 cc, boiled for 10 minutes after the addi- 

 tion of 1 cc. of a 20 per cent solution of ferrous sulphate containing also 1 per 

 cent of ferric chlorid, cooled, acidifled with hydrochloric acid, and 10 cc. of 

 glycerol added. After standing for about 18 hours the mixture is transferred 

 to a graduated cylinder, diluted to 50 cc. with water, and the blue coloration 

 compared in tubes of 1 in. diameter with standards prepared from known quan- 

 tities of hydrocyanic acid. When the amount of hydrocyanic acid present is not 

 less than 0.001 gm. the standards may be made up directly, but with smaller 

 quantities it is necessary to dilute to 150 cc. and then concentrate as in the 

 preparation of the solution from the plant material. 



" From determinations of hydrocyanic acid in millet and guinea corn plants 

 of various ages it was found that all the young plants contained a cyanogenetic 

 glucosid, while the full-grown plants were free from this substance. In the 

 case of guinea corn the yield of hydi'ocyanic acid reached a maximum (0.01 

 per cent) in the 12-in. plants and decreased as growth proceeded. With millet 



