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 (incorrectly called poplar) is employed for wagon bodies and often for house finishing. It often resembles curly maple.

Beauty of grain and polish gives wood value for furniture, pianos, and the like. Mahogany and white oak are most beautiful, although red oak is also used. Oak logs which are first quartered and then sawn radially expose the beautiful silver grain (medullary rays). Fig. 86 shows one mode of quartering. The log is quartered on the lines a, a, b, b; then succeeding boards are cut from each quarter at 1, 2, 3, etc. The nearer the heart the better the "grain": why? Ordinary boards are sawn tangentially, as c, c. Curly pine, curly walnut, and bird's-eye maple are woods that owe their beauty of grain to wavy lines or buried knots. Merely a stump of curly walnut is worth several hundred dollars. Such wood is sliced very thin for veneering and glued over other woods in making pianos and other pieces. If the cause of wavy grain could be found out and such wood grown at will, the discovery would be very useful. Maple is much used for furniture. Birch may be colored so as very closely to represent mahogany, and it is useful for desks.

Special Products of Trees.—Cork from the bark of the cork oak in Spain, latex from the rubber and sap from the