[AS.] A tree of several species belonging to the genus Betula-as the white or common birch - the most widely diffused, the dwarf birch, the paper or canoe birch, the yellow birch, and the black or cherry birch. The common birch is called silver birch or lady birch ; it has small green leaves, elegant drooping boughs and silver-white bark, and grows on the bleak mountain side. From the bark of the common birch an oil is obtained which is used in the preparation of real and imitation Russian leather; also a resinous substance called birch camphor or betulin is got from the outer bark of the tree. The birch of Jamaica is a kind of turpentine tree. The dwarf birch is a mere bush, and is the last shrub found on drawing near the eternal snow of the pole. Dye is prepared from birch leaves; and the wood makes good charcoal for gunpowder, and is used for smoking hams and fish. The wood is used by cartwrights, upholsterers, and turners; and the bark being impervious to water, is used for canoes and for preserving roofs. An oil similar to winter-green oil is prepared from the black birch.