durable when exposed to the air; but that it is now largely manufactured into coarse lumber for the outside finish of buildings, and is also used for railway ties and water-pipes. James M. Macoun, in The Forest Wealth of Canada, p. 82, says: "Though little inferior to white pine as rough lumber, a prejudice has for a long time existed against this wood, which is only now dying out. As a coarse lumber it to-day commands almost as high a price as pine. It is one of our best woods for wharves and docks, and great quantities are used annually for piles." It is not, so far as I can learn, imported into Europe. The value of its bark, however, for tanning heavy leather has long been known, and it is used more largely than any other in Canada and the Eastern States of America, often mixed with oak bark in order to modify the red colour of the leather tanned with it alone.[1]
Canada pitch, made from the resin of this tree, and oil of hemlock, distilled from its twigs, were formerly used to some extent in medicine, but are not now of any commercial importance. (H.J.E.)
TSUGA CAROLINIANA, Carolina Hemlock
- Tsuga Caroliniana, Engelmann, Coulter's Bot. Gazette, vi. 223 (1881); Sargent, Gard. Chron. xxvi. 780, fig. 153 (1886), Silva N. Amer. xii. 69, t. 604 (1898), and Trees N. Amer. 49 (1905); Kent, Veitch's Man. Coniferæ, 466 (1900).
A tree attaining in America 70 feet in height with a girth of 6 feet. Bark reddish brown, and deeply divided into broad, flat, connected scaly ridges. Young shoots shining grey, with scattered short pubescence in the furrows between the glabrous leaf-bases. Leaves pectinately arranged, those on the upper side of the branchlet shorter than the others, ¼ to ¾ inch long, linear-oblong, uniform in breadth or slightly narrowed towards the rounded apex, which is occasionally minutely emarginate; dark green and shining above, with a median groove either continued up to the apex or falling short of it; lower surface with distinct midrib and two narrow, well-defined white stomatic bands, the edges being green; margin entire. Buds reddish brown, ovoid, sharp-pointed; scales indistinctly keeled and pubescent.
Cones on short stout stalks, pendulous or deflected, cylindrical-oblong, 1 to 1½ inch long, consisting of five series of scales, five scales in each series. Scales oblong-orbicular, rounded and slightly narrowed at the apex, pubescent externally, edge thin and bevelled. Bract concealed, wedge-shaped at the base, rounded at the apex. Seed with a long wing, which is decurrent half-way down its outer side.
Tsuga Caroliniana appears to be the American representative of Tsuga
- ↑ Prof. H.R. Procter of the Leather Industries Department of Leeds University, tells me that though the bark is still the principal tanning material of North America, it has been cut so recklessly that in many districts the supply is now insufficient, and is supplemented by extracts of other materials, especially that of Quebracho wood (Loxopterygium). In England its use was at one time considerable, but it is no longer a specially cheap material, and its colour has now to a large extent prevented its employment. The bark appears to contain from 8 to 12 per cent of a catechol tannin, yielding large quantities of insoluble "reds," and in this respect it is very inferior to the bark of the common spruce fr, which is largely employed in Austria, though it does not seem to be used in England.
