The sulphate of an alkaloid, prepared from the powder of various kinds of Cinchona and Remijia bark.

Preparation. - By extraction with spirit after the addition of lime, or by the action of alkali on an acidulated aqueous infusion with subsequent neutralisation of the alkaloid by sulphuric acid and purification of the resulting salt.

Characters. - Filiform, silky, snow-white crystals, of a pure intensely bitter taste.

Solubility. - It is sparingly soluble in water, that is 1 part in 700 or 800 parts, at common temperatures, yet imparting to the water a bluish tint or fluorescent appearance. Entirely soluble in water acidulated by sulphuric acid.

Reactions. - Its solutions give with chloride of barium a white precipitate insoluble in nitric acid. When treated first with solution of chlorine and afterwards with ammonia they become of a splendid emerald-green colour, and solution of ammonia gives with them a white precipitate of quinine soluble in ether, and in excess of the solution of ammonia. It dissolves in pure sulphuric acid with a feeble yellowish tint, and undergoes no further change of colour when gently warmed. For the mode of testing the purity of the salt, vide B.P.

Preparations.

B.P.

Dose.

Ferri er Quininae Citras .............................................................

5-10 gr.

Tinctura Quininae Ammoniata ..................................................

1/2-2 fl. dr.

Vinum Quininae ......................................................................

1/2-1 fl. oz.