Glycol — Chambers's Encyclopaedia

Glycol is the type of a class of artificial compounds, whose existence was inferred, and afterwards discovered, by Wurtz. In their chemical relation and properties they form an intermediate series between the monatomic alcohols, of which common alcohol is the type, on the one hand, and the triatomic alcohols, a class of bodies of which ordinary glycerine is the type, on the other. The name of glycol, formed from the first syllable of glycerine and the last of alcohol, has been given to express this relation. The glycols are accordingly termed diatomic alcohols. Ordinary glycol is formed from ethylen, $C_2H_4$ , and hence may be called ethyl-glycol, to distinguish it from propyl-glycol, which is formed from propylen, $C_3H_6$ , from butyl-glycol, which is formed from butylen, $C_4H_8$ , or from amyl-glycol, which is formed from amylen, $C_5H_{10}$ . Glycol is a colourless, slightly viscous fluid, with a sweet taste, and its composition is expressed by the formula $C_2H_4(OH)_2$ . See Schorlemmer's Manual of the Chemistry of the Carbon Compounds.