JAL′APIN. C34H56O16. Syn. Jalapina. Jalap resin is commonly sold under this name, but pure jalapin is prepared by one or other of the following formulæ:—
Prep. 1. The liquid filtered from the jalapate of lead in preparing jalapic acid is a solution of acetate of jalapin, which, after any trace of lead is removed, by adding a few drops of dilute sulphuric acid, and filtration, yields the whole of its jalapin, as a precipitate, on the addition of 5 or 6 times its volume of water; this is collected, washed with a little cold distilled water, and dried by exposure to a current of warm dry air.
2. (Hume.) Coarsely powdered jalap is digested in strong acetic acid for 14 days, the tincture filtered ammonia added in excess, and the whole agitated strongly; the mixture is then filtered, the deposit washed in cold water, redissolved in acetic acid, reprecipitated by ammonia, and again washed and dried.
3. (Kayser.) Pure jalap resin, in powder, is digested for some time in boiling ether, by which means the jalapic acid is removed, and pure jalapin remains undissolved.
Prop., &c. A transparent, colourless, scentless, insipid resin, very soluble in alcohol, but insoluble in ether. It is the active purgative principle of crude jalap resin.
JAMAI′CINE. Syn. Jamaicina. A peculiar alkaloid obtained by Huttenschmidt from the bark of the Cabbage-tree (Andira inermis).
Prep. The aqueous solution of cabbage-tree bark, treated with sulphuretted hydrogen and evaporated.
Prop. Yellow crystals soluble in water and, to a limited extent, in alcohol; fusible, and very bitter tasted. It forms salts with the acids, which, in small doses, produce restlessness and trembling; and in larger ones, purging. It is said to be vermifuge.
JAMES’S POWDER. See Powders.
JAMS. Syn. Preserves. Conserves of fruit with sugar, prepared by boiling. In the latter respect they differ from the conserves of the apothecary.