Choh Butyl Alcohols. Four isomeric alcohols of this formula are known; two of these are primary, one secondary, and one tertiary (see Alcohols). Normal butyl alcohol, CH·(CH)·CHOH, is a colourless liquid, boiling at 116.8°, and formed by reducing normal butyl aldehyde with sodium, or by a peculiar fermentation of glycerin, brought about by a schizomycete. Isobutyl alcohol, (CH)CH·CHOH, the butyl alcohol of fermentation, is a primary alcohol derived from isobutane. It may be prepared by the general methods, and occurs in fusel oil, especially in potato spirit. It is a liquid, smelling like fusel oil and boiling at 108.4° C. Methyl ethyl carbinol, CH·CH·CHOH, is the secondary alcohol derived from n-butane. It is a strongly smelling liquid, boiling at 99°. Trimethyl carbinol or tertiary butyl alcohol, (CH)·COH, is the simplest tertiary alcohol, and was obtained by A. Butlerow in 1864 by acting with zinc methyl on acetyl chloride (see Alcohols). It forms rhombic prisms or plates which melt at 25° and boil at 83°, and has a spiritous smell, resembling that of camphor.