Of all the broad-leaved trees the oak is probably the most valuable, and has for ages stood as a type of strength. It is widely scattered in various parts of the world, and nearly three hundred varieties have been noted.

Oak is distinguished for its combination of useful qualities. It is hard, tough, elastic, heavy, durable, stiff (except after steaming, when it readily bends), and durable when exposed to the weather or to the soil. Oak is more or less subject to checking. It is strongly impregnated with tannic acid, which tends to destroy iron fastenings.

American white oak. This important variety is found in North America, and from it is obtained most excellent timber. It is used for a variety of purposes too great to be specified, from the construction of buildings and ships to furniture and agricultural implements, carriages, etc. It is an invaluable wood.

British oak has long been held in the highest regard for its combination of valuable qualities, and has been used for more purposes than can be here mentioned.

The live oak, found in southern parts of North America, may be mentioned as a valuable wood, very strong, tough, and durable, which, before the introduction of iron and steel in shipbuilding, was extensively used in that business ; but it is excessively hard and unsuited to amateur work.

Varieties of red oak are extensively used, but, though valuable, are of inferior quality to the white oak. Other varieties largely used in England and on the Continent are seldom marketed in the United States.