It is most easily obtained in a state of absolute purity by the action of spongy platinum and atmospheric air upon potatoe Fusel oil.
Valerianic acid is composed of C‗{ 10} H‗{ 9} O‗{ 3}, H O. It possesses a well known characteristic odour, an acrid burning taste, and produces a white spot on the tongue. It boils at 348° Fahr., and dissolves in 26 parts water; it also forms a second hydrate.[8]
The potash salt was prepared by saturating the acid with liquor potassæ, and evaporating carefully until aqueous vapour ceased to be given off: it should be, while still warm, cut up and preserved in well stoppered bottles. It does not crystallize, but forms a semi-transparent colorless mass, very much resembling phosphorus in appearance. It (probably from its compactness) produces when sharply struck with any hard body a metallic sound, somewhat like that occasioned when a bell of camphor is struck in a similar manner. It is deliquescent, and very soluble.
The soda salt was prepared in the same manner as the potash salt, cut up into pieces while warm, and preserved in stoppered bottles: it is in snow-white masses composed of minute crystals; it is deliquescent, and very soluble. The ammonia salt was prepared by saturating the acid with strong liquor ammoniæ, and evaporating at a temperature not exceeding 100° Fahr., until crystals appeared on the surface of the liquid. When it was set aside for further crystallization, the mother liquor was allowed to drain off, the crystals were placed upon bibulous paper, and finally dried _in vacuo_, over oil of vitriol. They are { 111} of a tabular form; when held between the fingers for a moment, they become liquid. They are deliquescent and dissolve readily in water.
The baryta salt was prepared by adding the acid to carbonate of baryta in excess, which had been previously mixed with water; a gentle heat was applied, and, when the disengagement of carbonic acid had ceased, the excess of carbonate was filtered off; the filtrate was evaporated very carefully, until aqueous vapour ceased to be given off, it remained a transparent gummy mass, readily soluble in water.
The strontia, lime, and magnesia salts were prepared in the same manner as the baryta salt. The two former are crystalline, and do not deliquesce by exposure to the atmosphere; they are soluble. The lime salt crystallizes in nacreous plates; it effloresces when exposed to the atmosphere; it is beautifully white.