VALERIA'NIC or VALERIC ACID is one of the volatile fatty acids represented by the general formula HO,C,„112„—,03, or c2„rio,. Its composition is represented by the formula and among its chief properties it may be noticed that it is a limpid, colorless, oily fluid of a penetrating odor, allied to that of valerian root, and an acrid taste. It renders paper transparent, but the spots disappear on exposure to the air. Its specific gravity is 0.94, it boils at 347°, and may be distilled without change; and its vapor is inflammable. It is only slightly soluble in water, but dissolves in alcohol and ether in all proportions. It exists in and is obtained by distilling valerian root with water acidulated with sulphuric acid. It may be similarly obtained from angelica root, and some other vegetable sources. It is also formed during the oxidation of fats and fatty acids (especially oleic acid), either by nitric acid or mere exposnre to the air, by the oxidation and putrefaction of the albuminates, etc., but the best method of procuring it is by distilling a mixture of amylic alcohol (or fousel oil) with bichromate of potash and sulphuric acid.
The salts of valcrianic acid—the valerianates or valerates, as it is now becoming the fashion to call them—are formed either by saturating the base or its carbonate with the free acid, or by double decomposition, their generalforrnula.being IIIO,Cialg03, when
bI is any metal. The alkaline valerianates are very soluble, and are not easily obtained in crystals; but most of the other salts occur in nacreous scales, and all of them, when moist, have the smell and taste of valerian.
The following salts are used in medicine: valerianate of soda, which is included iu pharm. Br. valerzanate of zinc, which is also included in platrm. Br., and occurs in bril liant white pearly tabular crystals, with a feeble odor of valerianic acid and a metallic taste, is scarcely soluble in cold water or in ether, but insoluble in hot water and alcohol. Besides these officinal salts, the valerianates of ammonia, of iron, and of quinia are employed in the same cases as the preparations of valerian, the doses averaging from half a grain to three or four times that amount three times a day in pills, except in the case of the ammonia salt, which is best given in solution. Valerianate of oxide of amyl is a volatile fluid with a penetrating odor of apples, boiling at about 360°, slightly soluble in water, but dissolving freely in spirit and in ether. In the form of a dilute spirituous solution, it so strongly resembles apples in its smell, that it is used in perfumery under the title of oil of apples.