* (a) It has since come more into use in flatulent and spasmodic complaints, the gout in the stomach, nervous asthmas, and the like. Though it will not mix with water, it may be diffused in a sufficient quantity of it so as to be taken without much difficulty.

Liquor aethe-reus vitrio-licus Ph. Ed.

aether vitriolic. Ph Lond,

The vitriolic acid saturates a larger quantity of fixt alkaline salts than any of the other acids, and dislodges therefrom such other acids as have been previously combined with them: of the strong spirit or oil of vitriol, about five parts are sufficient for eight of the common vegetable fixt alkalies. The neutral salt resulting from its coalition with this kind of alkali, is of a bitterifh taste, very difficultly soluble in water, and scarcely fusible in the fire: in small doses, as a scruple or half a dram, it is an useful aperient; in larger ones, as four or five drams, a mild cathartic, which does not pass off so hastily as the sal catbarticus, and seems to perform its office more thoroughly. This salt has been commonly prepared with the alkali obtained from tartar, and is hence called vitriolated tartar: some dilute the oil of vitriol with six times the quantity of warm water, and drop into it a solution of the alkaline salt till a fresh addition occasions no further effervescence; others direct it to be made from the residuum after extracting the nitrous acid from nitre by means of the vitriolic (see Nitrum), but in order to get rid of the superfluous acid the matter is first to be ex-posed to a strong heat, and then dissolved in boiling water, and the salt crystallised.

With the mineral fixt alkali, and the earth called magnesia, this acid forms compound salts of a bitterer taste, somewhat less purgative, and much easier of solution, than that with vegetable alkalies: with volatile alkalies a very pungent ammoniacal salt, whose medicinal effects are not well known. The strong acid, boiled on argillaceous earths to dryness, corrodes a portion of them, and concretes therewith into an austere styptic salt. Calcareous earths it does not dissolve into a liquid state, but may be combined with them, by precipitation from other acids, into an indissoluble concrete seem-ingly of no medicinal activity. Among metallic bodies, it dissolves zinc and iron readily; copper, silver, quick-silvcr, lead, and tin, very difficultly: it is fitted for acting on the two first by dilution with three or four times its quantity of water: the others require the undiluted acid, and a heat sufficient to make it boil; when, the more phlegmatic parts exhaling, so much of the pure acid matter remains combined with the metals, as to render them, in part at lest, dissoluble in water; see the respective metals.

Sal enixum & Arcanum duplicatum quibusdam.

Alcal. fix. veget. vitriol, vulgo tarta-rum vitrio-latum Ph, Ed.

Kali vitrio-lat. Ph. Lond.

The medical qualities of the acid in its vola-tile state are very little known, and those of the combinations thereof with alkalies not at all, though they should seem to deserve inquiry. The volatile acid of burning brimstone may be commodiously transferred into fixt alkalies, by dipping linen cloths in a strong solution of the alkali and suspending them over the fumes, of which they will quickly imbibe so much as to neutralize the alkali: this neutral salt being rubbed off, the cloths may be again moistened with the alkaline lye, exposed to the acid fumes, and these processes alternately repeated (a). The neutral salt thus obtained differs greatly in its taste and other properties, and doubtless also in its medical virtues, from that which is produced by the coalition of the fixt acid with the same alkali, that is, from vitriolated tartar. It dissolves more easily in water, and shoots, not into octangular crystals, but into small slender ones like short needles. On adding to it the fixt vitriolic acid (or even the weaker acids of nitre or sea-salt) the volatile acid is disengaged from the alkali; and though, in the compound salt, its pungent smell was wholly suppressed, it now rises in distillation as pungent and suffo-cating as the original fumes of the brimstone. The neutral salt, in a dry form, may be kept unchanged for years: dissolved in water, and exposed for some time to the air, or if roasted with a gentle heat, it becomes the same with vitriolated tartar,

(a) Vide Stahlii Experimenta & animadverfiones ccc.