Preparation. - From the mother-liquors of the crystallisation of the sulphates of quinine, cinchonidine, and quinidine, by precipitating with caustic soda, washing with spirit until free from other alkaloids, dissolving in sulphuric acid, purifying with animal charcoal, and allowing to crystallise.

Characters. - Hard, colourless, short, prismatic crystals, with a vitreous lustre. The aqueous solution has a bitter taste; the acidified solution is not fluorescent (p. 941).

Solubility. - Soluble in water and in chloroform, almost insoluble in ether and in solution of ammonia, readily soluble in rectified spirit and in diluted acids.