. Contributions from the Botanical Laboratory, vol. 1. Botany; Botany. 54 Trimble- Mangrove Taufiin, composition with ether, and, after removing the latter, dis- solving in water, and applying the usual reagents, a catechol tannin was indicated. Hydrolysis.— gramme, after boiling for three hours with a two per cent, solution of hydrochloric acid (absolute HCl), yielded a red insoluble decomposition product, and a sub- stance capable of reducing Fehling's solution to an extent which indicated P^r cent, of glucose. The above red product was readily oxidized by nitric acid yielding a red
. Contributions from the Botanical Laboratory, vol. 1. Botany; Botany. 54 Trimble- Mangrove Taufiin, composition with ether, and, after removing the latter, dis- solving in water, and applying the usual reagents, a catechol tannin was indicated. Hydrolysis.— gramme, after boiling for three hours with a two per cent, solution of hydrochloric acid (absolute HCl), yielded a red insoluble decomposition product, and a sub- stance capable of reducing Fehling's solution to an extent which indicated P^r cent, of glucose. The above red product was readily oxidized by nitric acid yielding a red- brown solution which rapidly faded, and which with water became paler, precipitation taking place at the same time. The original product was not completely soluble in cold or hot alcohol nor in ammonium hydrate. That which did dis- solve in alcohol was not precipitated by a large quantity of water. These properties indicated the presence of gallic acid, ellagic acid and phlobaphenes. Composition. After repeated precipitation of the tannin until it was of a light reddish-yellow color, it was dried at 120° and sub- mitted to elementary analysis with the following results : (i) .2353 gramme gave .5188 CO2 and .1023 H2O. (2) .2475 " " .5414 CO2 and .1027 H2O. (3) -2556 " " .5577 CO2 and .1070 H2O. indicating the following percentages : (I) (2) (3) Average. c. 59-66 59-51 59-76 H. 4-65 4-69 0. 35-04 35-73 35-84 35-55 , Calculated for v C25H25O11 C20H20O9 C27H24O11 59-4° 4-99 4-95 4-68 35-13 35-65 The formula C25H25O,, comes the nearest to representing the average percentages obtained; the formula C20H20O9 is that given by Dragendorff for rhatania-tannin; and the for- mula C^eH^^Ox, is the one given by Rochleder for horsechest- [Vol. I, Plate VII.] Bot, Cont. Univ. Pennsylvania. \. ON Mangrove Tannin. I!. Please note that these images are extracted from scanned page images that may have been digitally enhanced for r
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