Morphiometric Assay of Opium.
By DR. THEODORE SCHLOSSER.
The author regards Mohr's process, with the improvements suggested by Jakobson and Hager, as the most advantageous. He operates as follows: 200 grains of opium are digested over night in a tared 8 oz. flask with 2 oz. distilled water, until a uniform mixture, free from lumps, is obtained. 50 grs. recently prepared burned lime are slaked with about 20 drops of distilled water, then mixed with 1 oz. of water and added to the opium infusion. Water is now added until the mixture weighs 1850 grains (1600 water, 200 opium, 50 lime). The flask is then kept in boiling water for one hour, and its hot contents poured on a small filter, which has not been previously moistened, but is kept covered with a glass plate. Neither flask nor filter are rinsed with water. The filtrate is then weighed and 3 per cent. deducted therefrom; the remaining figure represents, according to the author's investigations, the weight of pure water contained in the filtrate. If the filtrate weighs 1100 grains, it contains 1067 (1100-33) grs. water, and represents 1600:1067::200:133 grs. opium. The filtrate is heated in a water-bath, 70 grs. granulated chloride of ammonium are dissolved in it by careful agitation, the whole again heated in a water-bath, and, after cooling, 40 grs. ether are mixed in by agitation, and the whole set aside for an hour. Should the ether not have completely prevented the adhesion of the morphia to the glass, warm water is poured upon the outside of the flask, when the alkaloid can be readily detached, and is collected upon a small filter, washed with an ounce of water and dried. Narcotina is removed by washing it three times with 40 grs. of chloroform, after which the filter is again dried. The weight of the morphia represents the amount obtained from 133 grs. of crude opium. If in the meantime another portion of opium, obtained from different parts of the cake, has been thoroughly dried, it is easy to calculate the morphia contained in 100 grs. dry opium.
The assay is finished in 24 hours, and the morphia is obtained in a very pure condition, little colored and in a crystalline form.—Zeitschr. d. Oester. Apoth. Vereins, 1871, 10-12.