De Sussex’s process for the manufacture of nitrate of potash is as follows:—A solution is made of 166 pounds of nitrate of lead, and another of 76 pounds of chloride of potassium. The two solutions are then mixed, when double decomposition takes place, chloride of lead being precipitated, and nitrate of potash obtained in solution. In order to avoid the presence of lead in the nitrate of potash, a small portion of caustic or carbonated lime or magnesia is added, by which means any portion of the chloride of lead remaining in solution is precipitated. The solution of nitrate of potash is then evaporated and crystallized.
Nitrate of soda is obtained in the same way, by substituting sixty-six pounds of chloride of sodium for the chloride of potassium above mentioned.—Pharmaceutical Journal and Transactions, July 1, 1852.
ON TINCTURE OF OPIUM.
The Pharmaceutical Society of Antwerp has employed a commission composed of its members to determine the best menstruum for the preparation of tincture of opium. It has arrived at the following results:—
1. Good opium gives, when treated with water, less extract than bad or adulterated.
2. By warm digestion, a stronger solution is obtained than by cold infusion.
3. Alcohol must be preferred to wine in the preparation of tincture of opium.
4. Narcotine, although alone insoluble in water, becomes partially extracted with the other ingredients of opium. When it is advisable to avoid the removal of narcotine, proceed {280} as follows:—Treat carefully prepared aqueous extract of opium with, boiling alcohol; this dissolves out the narcotine and morphine, from which solution, when cold, the narcotine separates.
After the precipitation, whatever ingredients are necessary to form the tincture are to be added to the alcoholic solution.