Active Ingredients. - Winter's bark, according to the analysis of Henry, contains volatile oil, resin, coloring' matter, tannin, acetate and sulphate of potash, chloride of potassium, oxalate of lime, and oxide of iron. Of these the really active ingredients are probably the tannin and the volatile oil. The latter is divisible into two substances: one is a thin, greenish yellow fluid, the other a fatty body of acrid and burning taste.

Therapeutic Action. - The union of the styptic tannin and the stimulating volatile oil renders Winter's bark a tonic, with qualities that one would suppose to be very valuable in various disorders. It was employed for much the same purpose as Canella, which superseded it, and which has itself, in turn, fallen nearly out of use. Upon the whole, it seems to be a fairly active stomachic tonic, well applicable to chronic atonic dyspepsia; it has also been used in paralysis, scurvy, and other conditions of debility.

Preparations and Dose. - None officinal. The dose of the pow dered bark is 3 ss. - 3 j. (2. - 4.), which may be given in infusion.