This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
This has been of late rejected from the Pharmacopoeia, and owes what little attention is now paid to it to old associations. It is the bark of Drimys Winteri ( Wintera aromatica, Willd.), an evergreen tree, growing in the southern extremity of the American continent, along the straits of Magellan, and thence northward to Chili and Brazil. As found in commerce, the bark is in quills about a foot long by an inch in diameter, or in larger flat pieces. On the outside it appears as if it had been scraped or rubbed, and has a pale-yellowish or reddish-gray colour, with red elliptical spots; the inner surface is reddish-brown or cinnamon coloured. Its powder resembles that of Peruvian bark. Its smell is fragrant, its taste hot, pungent, and spicy. Its chief active constituent is a peculiar volatile oil, with which there is also a somewhat acrid resin. and sufficient tannic acid to cause the infusion to be darkened by the salts of iron.
Winter's bark was first made known by Captain Winter, who commanded one of the vessels in Drake's famous expedition, and, on his return to England, in 1579, brought some of the bark with him. It has often been confounded with canella, which it resembles in appearance; but it may be distinguished by its dark inner surface, while that of canella is white, and by affording with reagents evidence of containing tannic acid, which canella does not.
Its medical properties are essentially the same as those of canella, and it may be used for the general purposes of the aromatics; but it is seldom to be found in the markets of the United States, and is little employed. The dose of the powder is about half a drachm.