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ound to contain saccharic acid: the acid from C and B contained a dibasic acid which appeared to be tartaric acid. The isolation of (1) isosaccharinic and (2) dioxybutyric acid from the products of digestion of the oxycelluloses with lime-milk at 100 deg. was effected by the separation of their respective calcium salts, (1) by direct crystallisation, (2) by precipitation alcohol after separation of the former. CELLULOSES, HYDRO- AND OXYCELLULOSES, AND CELLULOSE ESTERS. L. VIGNON (Bull. Soc. Chim., 1901 [3], 25, 130). (a) _Oxycelluloses from cotton, hemp, flax, and ramie._--The comparative oxidation of these celluloses, by treatment with HClO_{3} at 100 deg., gave remarkably uniform results, as shown by the following numbers, showing extreme variations: yields, 68-70 p.ct.; hydrazine reaction, N fixed 1.58-1.69; fixation of basic colouring matters (relative numbers), saffranine, 100-200, methylene blue, 100-106. The only points of difference noted were (1) hemp is somewhat more resistant to the acid oxidation; (2) the cotton oxycellulose shows a somewhat higher (25 p.ct.) cupric reduction. (b) _'Saccharification' of cellulose, cellulose hydrates, and hydrocellulose._--The products were digested with dilute hydrochloric acid six hours at 100 deg., and the cupric reduction of the soluble products determined and calculated to dextrose. 100 grms. of gave reducing products equal to Dextrose Purified cotton 3.29 " Hydrocellulose 9.70 Cotton mercerised (NaOH 30 deg. B.) 4.39 Cotton mercerised (NaOH 40 deg. B.) 3.51 Cellulose reprecipitated from cuprammonium 4.39 Oxycellulose 14.70 Starch 98.6 These numbers show that cellulose may be hydrated both by mercerisation and solution, without affecting the constitutional relationships of the CO groups. The results also differentiate the cellulose series from starch in regard to hydrolysis. (c) _Cellulose and oxycellulose nitrates._--The nitric esters of cellulose have a strong reducting action on alkaline copper solutions. The author has studied this reaction quantitatively for the esters both of cellulose and oxycellulose, at two
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