TIMBER, trees cut down, squared, or capable of being squared, into beams, rafters, boards, planks, etc., to be em ployed the construction of houses, ships, etc., or in carpentry, joinery, etc. Timber is usually sold by the load. A load of rough or unhewn timber is 40 cubic feet, and a load of squared timber 50 cubic feet, estimated to weigh 2,000 pounds. In the case of planks, deals, etc., the load consists of so many square feet. Thus, a load of one-inch plank is 600 square feet, a load of planks thicker than one inch equals 600 square feet divided by the thickness in inches. The term is often used for all kinds of felled and seasoned wood. It is also a general term for growing trees yielding wood suitable for constructive purposes. The chief are fir, pine, oak, ash, elm, beech, sycamore, walnut, chestnut, mahogany, teak, etc.
In the United States there are 300 species of trees, the smallest of which grows to a height of 30 feet. In South America the number is much greater, and India possesses about 900 species of timber trees. The species in England do not exceed 30, and in France or Ger many there are only a few more. Yet, though the kinds of wood are so much more limited in European countries, there are almost as few in general use in the United States as in Europe. The small ness of the number of species of timber known to commerce is at first glance very remarkable, but it is accounted for in this way. The great consumption of timber is for architectural and other con structive works which are usually car ried out on a scale of some magnitude, and for such purposes large quantities of the kind or kinds chosen are required. It is very desirable, therefore, that the wood selected should be plentiful, ble, more or less easily worked, fairly uniform in quality, and moderate in price.
As yet the very useful timbers have been obtained from gregarious species of trees growing in the forests of the N. temperate regions of the globe, and the most important of these are a few kinds of fir and pine. From the tropics, where the social species are fewer, come the harder, heavier, and more richly colored or figured kinds, some of which are used in Europe and North America only for furniture and decorative purposes. Some
of these tropical woods are, however, of extraordinary strength, and possess other valuable properties which will bring them sooner or later into use for building pur poses. This is all the more certain to be the case as both in North America and in Europe the forest-covered land is be ing stripped of its best timber at a rapid ly increasing rate. Trees are of such slow growth that it takes many years before they are large enough to yield useful timber; so that when the primitive forests of a country are once cut down the keeping up of a supply by planted trees is a very difficult matter.
Chief Commercial Timbers.—The fol lowing are the best known and most used timbers in Great Britain. Baltic redwood (Pinus sylvestris), perhaps the most gen erally useful of all, is employed for roof ing and flooring, and often for all other internal and external wood work of bet ter-class houses and other buildings. It is also used for paving streets and many other purposes. This wood in the cut state is called "yellow deal" in England. American yellow pine (Pious strobus), called white pine in its native country, is also very largely imported for the in ternal joiner work of buildings, parts of furniture, etc., but it is not suited for external work. Like the last, it is an excellent and easily worked timber. Bal tic white wood (Abies excelsa) has for a considerable number of years taken the place of redwood for joists, flooring boards, roof timbers, etc. It is a dis tinctly inferior wood. American pitch pine (Pinus rigida), found over a large extent of country in the Eastern States, is an important timber. It has been much used in England for open roofs and for the whole of the wood-fittings of churches, halls, and the like. The annual rings of this wood are strongly marked, so that its planed surface looks striped. It is a heavy and highly resinous, but not very easily worked wood. The Douglas or Oregon pine (A. Dottgrasii or Pseudotsu ga Donglasii) of northwestern America, between 200 and 300 feet in height, yields a timber of great length without knots, suitable for masts, spars, and many other purposes.