Thymol (C10H13OH) occurs chiefly in oil of thyme, but is also found in other vegetable sources. It may be obtained by adding caustic potash to the oil and then adding to the solution hydrochloric acid, which precipitates the thymol. It so forms colourless plate-like crystals, which melt at about 44° and boil if heated further. It possesses an odour resembling that of thyme, and is easily soluble in alcohol and ether. It is a phenol (q.v.), and so in many respects resembles carbolic acid; by reduction it yields the hydrocarbon cymene C10H14.