Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: convenience of comparison these results are tabulated, as follows: Mean raw lac Mean for lac hard- Mean for urushic Calculated for dried by heat, ened by enzyme, acid oxidized by C,,H,jOa chromic acid. C 75-47 70.85 71.52 71-79 H 8.97 8.22 8.23 7-69 N o.n 0.092 .... .... Ash 0.21 0.032 0 15.17 20.52 20.25 20.52 He c
...oncludes from the above analyses that the lac when hardened in the usual manner takes up one atom of oxygen for every molecule of urushic acid, becoming C14H18O3. This compound he names Oxyurushic acid. More recently Bertrand13 has worked upon Japanese lac; however he has contributed nothing of importance to the knowledge of the alcohol soluble substance. His principal work was upon the soluble ferment referred to elsewhere. EXPERIMENTAL INVESTIGATION. Three samples of lac were used in the following experiments. The first and second were in glass jars bearing original Japanese labels. The third was in a tin can. Apparently all were identical. The samples were all sent gratuitously to Prof. Tschirch. The first by forester Shirasawa, in Tokio, and others by the Rhus Company in Frankfort, a. M. to whom I here extend thanks. When separated according to the method of Ishimatsu they gave the following results: Parts soluble in alcohol 72.40% Parts soluble in water 4.05% Insoluble residue 2-35% Water and volatile matter 21.20% 1 have found, as will appear later, that Yoshida's Urushic acid may be separated by benzini into Benzin-soluble 78% Benzin-insoluble 22% and that the benzin soluble consists of three substances, one of which is a non-volatile poison, also that the gum and enzyme Ann. chem. phys. ser. XII, 1897, p. 115. (diastatic matter) cannot be separated, also that the lac contains acetic acid. The l...
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