SALT. A term commonly used in chemistry, to denote a compound in definite proportions, formed by the union of an acid with an alkaline, earthy, or metallic base. We have already given • brief enumeration of some of the most remarkable, under the article Cranaseity. In consequence, however, of the progressive discoveries which for the last half century have been continually made, and are still making, in chemistry, many deductions, which, at the time they were made, were .considered as conclusive facts, have since been either wholly abandoned, or subjected to considerable modifications. A salt has usually been denominated by chemists a neutral salt, when the proportions of the constituents are so adjusted, that the resulting substance does not afflict the colour of infusion of litmus or red cabbage. When the predominancy of acid is evinced by the reddening of these infheions, the salt is said to be acidulous, and the prefix or bi, h used to indicate the excess of acid thus we call one particular salt ;uperLtarbate of potash, and another, hi-sulphate of lime, where the acid Mete m excess. But when, on the contrary, the acid Matter is in too small a quantity to completely neutralise the alkalinity of the base, the salt is said to be with an Wm of base, and the prefix sub is attached to be name: thus we have the sub-phraphate of bismuth, &e.. We are indebted to Dr. Pearson for the introduction of these very convenient distinctions ; but, as Dr, Ure justly observes, "the discoveries of Sir H. Davy have taught us to modify our opinions condeiting saline constitution. Many bodies, such as culinary salt and muriate of linty, to which the appellation of salt cannot be refused, have not been proved to contain either acid or alkaline matter ; but must, according to the strict logic of chemistry, be regarded as compounds of ehlorine with made Dr. Ure further remarks, in stating the opinion of Sit H. Davy on the subject, "that very few of the substances which have always been considered as neutral salts, really contain in their dry state the acids and alkalies from which they were ft.m4 ; " and he instances the muriate and dudes, neither-of which, he says, contains either an acid or an alkali ; and, according to Gay Lune, the same may be inferred of the pruseista. The
most important general habitude of salts is their solubility in water, in which they usually crystalline, and, by its agency, are purified, being separated from i one another in the inverse order of their solubility.
The oommeteial name of a salt difibra from that by which it is known to chemists n it may therefbre beproper to show what kinds of salt are to be under stood by the popular names which they bear in the shops.
iharaerdocal Mutsu Salt, muriate of lime.
itoolioniacal Secret SW Glauber, sulphate of ammonia.
Artenical Neutral Sall of Maequir% Super-arsonists of potash.
Attn. Cathartic Shlt, sulphate of Magnesia.
Common Table Sall, muriate of coda. (We shall treat of this kind more at large in a subsequent part of this article.) Digestive Salt of 4's, or Diuretic Salt, sedate of potash.
Epsom Salt, sulphate of magnesia.
Febri Salt qf Sylvia., muriate of potash.
'.Fus Salt, phosphate of ammonia.
Fusible Salt of Urine, triple-phosphate of soda and ammonia.
Glauber's Salt, sulphate of soda.
Marine Sole, muriate of soda.
Marine Aril/Lwow Salt, muriate of alumina.
Microcosmic Sate, triple-phosphate of soda and Nitrous ilasmoniacal Salt, nitrate of ainradda.
Salt of Amber, succinio acid.
Salt of Bonsai., benzoic acid.
Sale of Canal, sulphate of magnesia • Salt if Coleotliar, sulphate of iron.
Salt of Egra, sulphate of magnesia.
Essential Salt of Lemons, super-oxalate of potash.
Salt of Saturn, acetate of lead.
Salt of Seidata, sulphate of magnesia.
Salt of Seignette, tnple-tartrete of potash and sod& Salt qf Soda, sub-carbonate of soda.
Salt of Sorrel, super-oxalate of potash.
Salt of Tartar, sub-carbonate of potash.
Salt of Vitriol, purified sulphate of sine.
Salt of Wisdom, a eampound-mtniate of mercury and ammonia. Perla& Salt, phosphate of soda.
Polyehrest Salt V Glauber, sulphate of potash.
Sedative Salt, boracic acid.
Spirit of Salt, muriatio acid.
Sulphsweense Salt of Stahl, sulphate of potash.
Wonderful Salt, sulphate of soda.
Wonderful Perlate Salt, phosphate of soda.