Boneset, Or Thoronghwort, the herb evpato-rium perfoliatum, an indigenous perennial plant growing in moist places, distinguished by the perfoliate character of its leaves, each pair of which are at right angles to those immediately above and below. It is a bitter weed or vegetable tonic, with a faint odor and a strong bitter taste. Hot water extracts its virtues, which are believed to reside chiefly in a bitter principle. The cold infusion acts as a mild, pleasant tonic; the hot infusion as a diaphoretic, and, when very strong, as an emetic. Strong infusions of boneset leaves are used as a substitute for Peruvian bark in cases of ague, and sometimes with success; but it is not always to be relied on. A pint of boiling water is poured upon an ounce of the dried leaves, or a pint of cold water upon an ounce of the fresh leaves, and allowed to stand two hours; it is then strained for use. A weak cold infusion is good for all cases of debility where tonics are prescribed. For ague as much should be taken as the stomach will bear, and it should be drunk warm.