A vegetable alkali obtained from cinchona (bark.) It is procured by the following process: a pound of bruised bark is boiled in about a gallon of water, containing three fluid drachms of sulphuric acid. A similar decoction is repeated with about half the quantity of liquid, and so on till all the soluble matter is extracted. The decections are then mixed together and strained, when powdered slaked lime is aided in a proportion somewhat greater than necessary to saturate the acid; the precipitate that ensues, a mixture of quinine and sulphate of lime, is collected, dried, and boiled for some minutes in strong alcohol, which is then decanted while still hot, and fresh portions succes sively added for the repetition of the same operation, until it ceases to act on the residuum, which is then merely sulphate of lime. The different alcoholic solutions are then put into a vessel, and considerably evaporated; during which, and especially on cooling, transparent plates of quinine are deposited. It is very insoluble in water, and its taste is very bitter. It unites with the acids, forming crystallizable salts. The sulphate is of a dull white colour, silky and flexible: it is, like the alkali, soluble in alcohol; and burns away without leaving any residuum.

M. Pelletier and Caventon state its component parts to be

Quinine ....................................................

100

Sulphuric acid ...........................................

10.9147

The acetate is remarkable for the manner in which it crystallizes. Its crystals are flat needles of a pearly lustre grouped in silky bundles, or in stars.