Magistery, a name given to almost every precipitate obtained by solution, as opposed to calx, which is procured wholly by calcination : it is chiefly employed to denote such precipitates as are used in medicine ; for instance, the magistery of bismuth, coral, crabs-eyes, etc.
Magistery of Bismuth is a fine powder, prepared by dissolving bismuth in nitrous acid, and pouring on it a large quantity of pure water, which precipitates the magistery to the bottom of the vessel. It is chiefly employed as a cosmetic by the gay and giddy, on account of the superior beauty and dazzling whiteness which it imparts ; but it is very pernicious to health, and eventually injures the skin.—See Bismuth.
Magistery of Coral, crabs-eyes, pearl, shells, chalk, and other absorbent matters, is prepared by dissolving any of these substances in the nitrous acid ; when they must be precipitated by fixed alkali, and repeatedly washed fa pure water, till the latter is per-feclly tasteless.
Magistery of Lead is the calx of that metal, dissolved in aqua-fortis, and precipitated with filtred saltwater, by which means the powder acquires a beautiful white colour. It is softened by repeated ablutions, and then mixed with pomatums for improving the skin and complexion of the face.—Like all other preparations of lead, this magistery is a slow poison, and will therefore never be used by those who have the least regard for their health.