a semimetal. For a description of the ores of this metal, the method of extracting it from these ores, and for its properties, see CALAMINE; CHEMISTRY-index; MINERALOGY, Vol. XII. page 128; METALLURGY, Part II. sect. xii.
Zinc, besides its medical qualities (for which see PHARMACY-index), is of great use in the arts: united with copper in different proportions, it forms brass and pinchbeck; and united with tin, it forms a kind of pewter.
Brass is formed by mixing two parts of copper with one of zinc; pinchbeck by mixing three or four parts of copper to one of zinc: when the metals are mixed in equal quantities they form a very exact imitation of gold. Its inflammable property renders zinc a useful ingredient in fire-works.
It has been proposed to substitute this semimetal instead of tin in the lining of copper vessels; the latter being thought insufficient to prevent the dangerous effects of the copper. Mr Malouin, who has made many experiments on the lining of vessels in this manner, affirms that it spreads more evenly on the copper than tin itself; that it is much harder and less fusible, and consequently more durable than tin. Mr Macquer owns these advantages; but thinks it dangerous to be used in culinary vessels, as it is soluble in vegetable acids, and the combination of it with the vitriolic acid is known to be a strong emetic. Gaubius also mentions a celebrated remedy for convulsive disorders, named luna fixa tude-manic which Macquer affirms to be strongly emetic in very small doses. "But, may it not be presumed (says Foucroy), that properties which are applicable only to the vitriol and flower zinc, cannot be applied to the semimetal itself, nor even, without farther experiments, to the salts formed by its combination with the vegetable acids." Mr de la Plaudie, doctor in medicine of the faculty of Paris, has changed this presumption into certainty by experiments made with great care on himself. He took the salts of zinc, formed by its combination with vegetable acids, in a much stronger dose than the aliments prepared in copper covered with zinc can possibly contain them, and found no dangerous effects to follow. However, since objects which relate to the health and lives of mankind cannot be treated with too much circumspection, it appears to be prudent, and even necessary, not to decide on the subject till after a great number of experiments, and that the action of zinc combined with the vegetable acids used in cookery have been fully ascertained. The flowers of zinc have been used as an antipathodic, and are an article of our present materia medica; but it does not clearly appear what success may be expected from them.