CHEMISTRY. 8o7 



sulphate, a process wliicli rendered the gliadin iiisohible in the strong 

 sohition in which the proteids were subsecineiitly rcdissolved. . . . 

 The proteose which we described we separated as such Ironi the extracts, 

 and couhl, therefore, by no possibility have mistaken gliadin for it." 



Preparation of soluble starch and starch solution, O. Foekster 

 {(Item. Zt<j., ;21 (JS97), Xo. C. p. 11). — SoIkIjIc slarch. — In n deep i)<>rce- 

 lain dish heat to boiling 200 to 300 cc. of water to which has been 

 added 5 cc. of hydrochloric acid (sp. gr. 1.124). Ivemove from the 

 llame and add gradually, with stirring, 20 to 25 gm. of starch made into 

 a uniform i)aste with a little water, continuing until the liquid becomes 

 of uniform consistency and tolerably thin. Now heat, with constant 

 stirring, until the solution becomes as thin as water and clear. Cool 

 and filter, precipitate with alcohol, and wash the precipitate with 

 alcohol until free from chlorin, and finally with ether; then dry, first in 

 the air and afterwards with gentle heat, or, better, over sulphuric acid. 



Starch soIiitio)i. — Dissolve 20 gm. of starch in the manjier above 

 described, with this difterence, that the hydrochloric acid is accurately 

 measured out and its acid content accurately determined with a view 

 to subsequent neutralization. The accurately neutralized solution of 

 starch is filtered and made to 1 liter with glycerin. 



To both of these i)reparations, the soluble starch as well as the solu- 

 tion in glycerin, iodin imparts a fjiultless blue. — J. t. Anderson. 



A ne^v method for the quantitative determination of crude 

 fiber, Lebbin {Arch. Hyg., i'8 (1897), No. 3, irp. 213-243).— Th^i author 

 enumerates over 30 methods which have been proposed for determining- 

 crude fiber, and describes experiments by himself to devise an improved 

 method, especially for grains and materials rich in carbohydrates. He 

 tried a long list of reagents, including water, potash solution, Schulze's 

 reagent, bisulphite solution, i)epsin-hydrochloric acid, and peroxid of 

 hydrogen, and gives the results with each. He finally settled upcm 

 peroxid of hydrogen, using a solution containing about 20 per cent bf 

 H2O2. Alone this had very little action on gelatinized starch, but when 

 a little ammonia was added the starch was rapidly dissolved t(» a clear 

 solution, oxygen and carbon dioxid being given off. Potato starch 

 was completely dissolved, but with starch from corn, rice, and wheat 

 small residues of intercellular tissue remained undissolved, and in the 

 case of wheat starch the hairs of the kernel were also found in the 

 residue. This latter point is said to furnish a convenient means of 

 distinguishing between wheat fiour and rice fiour. 



Filter paper treated with the reagent showed losses ranging from 

 2.725 to 5.65 per cent, and a samjile treated a second time showed a loss 

 of 1.46 per cent. The same paper lost 9.75 per cent by the Lange 

 method and 14.62 per cent by the glycerin -alkali method. Cotton 

 wadding showed a loss of 13.41 percent by the new method and 12.475 

 per cent by the Weende method; a finer quality lost 2.33 ])er cent by 

 the new method and 2.225 per cent by the Weende method ; and " wood- 



