Note 417 — MINERAL POISONS. (continued 3)

It may be obtained from opium by the following process, invented by Robiquet. Three hundred parts of pure opium are to be macerated during five days, in one thousand parts of common water; to the filtered solution, fifteen parts of perfectly pure magnesia (carefully avoiding the carbonate) are to be added; boil this mixture (A) for ten minutes, and separate the sediment (B) by a filter, washing it with cold water until the water passes off clear; after which, treat it alternately with hot and cold alcohol (12, 22. Bé) as long as the menstruum takes up any colouring matter; the residue is then to be treated with boiling alcohol (22, 32, Bé) on cooling, the solution will deposit the Morphia in crystals.

Rationale of the process. A soluble meconiate of magnesia is, in the first place, formed; (A) while the sediment (B) consists of morphia, in the state of mixture, with the excess of magnesia; the boiling alcohol, with which this residuum is treated, exerts no action upon the magnesia, but dissolves the morphia, and, on cooling, surrenders it in a crystalline state.