VITRIOL (derived from the Latin ritrurn, glass) is a term which the early chemists applied to glass-like salts, distinguishing them by their colors into blue vitriol, green vitriol, and white vitriol. Blue vitriol is still the popular name for sulpha;:e of copper, which may be obtained on a large scale in various ways, but most simply by boiling copper in an iron pot with dilute sulphuric acid, by which means we obtain a salt hav ing the formula, 5Aq, and crystallizing in oblique prisms of a clear blue color, which arc soluble in four parts of cold, and two of boiling water, and when moistened. redden litmus paper. In large doses, it acts as a powerful irritant poison, unless, as is frequently the case, it is rejected by vomiting. In small but repeated doses (as from half a grain, gradually increased to two grains, made into pills with conserve of roses), it acts as a tonic and astringent, and will often check the discharges in cases of chronic diarrhea and dysentery, when other medicines have failed; and according to Neligan, it has been found serviceable in croup by checking excessive bronchial secre tion. It has been much employed in cases of epilepsy, and is a valuable remedy in chorea and other spasmodic diseases, especially when they occur in weak constitutions about the period of puberty. Its use in doses of from 10 to 15 grains as an active emetic is mentioned in all works on materia medica; but sulphate of zinc in a dose of a scruple, is as efficacious, and safer. Externally, this salt ..in solution (varying from one to ten
grains in au ounce of water) forms a good application to indolent ulcers, aphthm, can crum iris, and the sore throat in scarlatina; it is also used in chronic ophthalmia, and as an injection in eases of urethral or vaginal 'discharges. In the solid state, it. is used as a caustic to repress excessive granulations (proud flesh), to destroy warts, and to excite indolent ulcers.
Green vitriol is the popillar name for sulphate of iron. Its characters, the method of obtaining it, and its therapeutic uses, are sufficientiy noticed in the article Ilion. • White will be described in the article Zrsc.
Oil of vitriol is the old name given to commercial sulphuric acid, in consequence of its oily appearance, and of its being formerly obtained from green vitriol.
Elixir of vitriol is the old name for the aromatic sulphuric acid of the pharmaeopceia. It is a mixture of three ounces of sulphuric acid and two pints of rectified spirit, in which powdered cinnamon and ginger have been digested. Its uses in doses of from ten to thirty minims, in a wine-glassful of water, are much the same as those of dilute sulphuric acid, but it is more agreeable to the taste, and sits more lightly on the stomach,