ALCOHOL, a term applied by chemists to the purely spirituous part of liquors that have undergone the vinous fermen tation. It is in all cases the product of the saccharine principle, and is formed by the successive processes of vinous fermenta tion and distillation. Various kinds of ardent spirits arc known in commerce, as brandy, rum, &c. ; but they differ in co lour, taste, smell, &c. The spirituous part, however, is the same in each, and maybe procured in its purest state by a second distillation, which is termed recti fication. See DisTrtwerrox, FERMENTA 'VON, and RECTIFICATION. Alcohol is procured most largely in this country from a fermented grain-liquor ; but in France and other wine countries, the spi rit is obtained from the distillation of wine, hence the term spirit of wine. Sec BRAN DT. Alcohol is a colourless, transparent liquor, appearing to the eve like pure wa ter. It possesses a peculiar penetrating smell, distinct from the proper odour of the distilled spirit from which it is pro. cured. To the taste it is excessively hot and burning; but without any peculiar flavour. From its lightness, the bubbles which are formed by shaking subside al most instantaneously, which is one me thod of judging of its purity. Alcohol may be volatilized by the heat of the hand. It is converted into vapour at the tempe rature of 55° of Fahrenheit, and it boils at 165°. It has never been frozen by any
degree of cold, natural or artificial, and on this account it has been much used in the construction of thermometers. Alco hol mixes with water in all proportions, and during the mixture heat is extricated, which is sensible to the hand. At the same time there is a mutual penetration of the parts, so that the bulk of the two liquors when mixed is less than when se parate ; consequently the specific of the mixture is greater than the meaa specific gravity of the two liquors taken apart. Alcohol is supposed to consist of Carbon 28.53 Hydrogen . . 7.87 Water 63 6 100.00 Its uses are many and important: it is employed as a solvent for those resinous gums which form the basis of numerous varnishes: it is employed also as the basis of artificial cordials and liquors, to which a flavour and additional taste are given by particular admixtures : it serves as a solvent for the more active parts of vege tables, under form of tinctures. The antiseptic power of alcohol renders it par ticularly valuable in preserving particular parts of the body as anatomical prepara tions. The steady and uniform heat which it gives during the combustion makes it a valuable material for burning in lamps.