Oil of wintergreen, a volatile oil distilled from Gaultheria procumbens.

Characters. - A colourless, yellow, or reddish liquid, of a peculiar, strong, and aromatic odour, a sweetish, warm, and aromatic taste, and a slightly acid reaction.

Solubility and Reactions. - It is readily soluble in alcohol. When heated to about 80° C. (176° F.) the oil should not yield a colourless distillate, having the characteristics of chloroform or of alcohol. On mixing five drops of the oil with five drops of nitric acid, the mixture should not acquire a deep red colour, and should not solidify to a dark red resinous mass (absence of oil of sassafras).

Composition. - Oil of wintergreen consists chiefly of salicylate of methyl, which forms about 9/10ths of it, the remaining 1/10 th being a hydrocarbon called gaultherilene.

Preparations.

dose.

Spiritus Gaultheriae (oil, 3; spirit, 97) .....................................

10-20 min.

Syrupus Sarsaparillae Compositus ..........................................

Trochisci Morphinae et Ipecacuanhae ...................................

Action and Use. - It is used on account of its agreeable smell and taste to flavour medicines. It is also given as an antipyretic to reduce the temperature in rheumatism, its antipyretic action being somewhat the same as that of salicylate of sodium or salicin.