Note: Do not rely on this information. It is very old.
Peppermint_1
Peppermint, Oil op, is the essential oil obtained by distillation from the peppermint plant, Mentha piperita. The oil is a colourless liquid with a pleasant odour, and strong peculiar taste. It has a specific gravity of about 85, and acts strongly on polarised light. [Polarisation.] If cooled, crystals of menthol form in the liquid, and it is largely used as a source of this substance.
Quantities are used in medicine as an anodyne, anti-spasmodic, and in cases of diarrhoea. It is also largely employed to disguise the obnoxious taste of medicines and for flavouring purposes, but the greatest quantity is employed for the production of peppermint lozenges.