There are but five kinds of wood in common use for carpentry in this country. These are spruce, pine, oak, hemlock, and chestnut.

Spruce (Abies) is indigenous to the colder parts of North America, where it grows in great abundance. For most qualities which constitute good framing-timber, it is excelled by no other wood in use.

There are two varieties, which are familiarly known as black or double (Pinus niger) and white or single spruce (Pinus alba). Of these, the black is of most value; it being much tougher than the white, and may be procured in much larger sticks. The foliage of this variety is darker and heavier. The white spruce is of a comparatively small growth; but the wood may be worked much smoother than the other variety. Spruce-wood, when seasoned, is of a clear yellowish white, the annual rings being distinctly marked by a darker tint of the same color, and having a silk-like lustre. A cubic foot, when seasoned, weighs thirty-one pounds and a half. It shrinks, in seasoning, about a seventieth part of its dimensions, and loses a fourth of its weight.

The principal defects of this wood are its liability to twisting and splitting in the sun, and its tendency to decay in all damp situations; but where due attention is paid to these points, and proper care is exercised to prevent the exposures named, little else need be done to insure the permanency of work composed of this wood.

Pine (Pinus) is next in value as material for a frame. Of this wood, there are many species. The family ( Conifera) to which it belongs is large, and comprises all that ranges from the most compact and hard spruce to the softest white pine. But two kinds, however, will claim our attention; the others, as framing-timber, partaking largely of the nature of spruce. Remarks relating to that wood may be applied with nearly the same propriety to all the harder varieties of pine.

The two varieties most in use are known as white pine and Carolina pine.

White Pine (Pinus strobus) abounds in all the northern portion of the United States, and is the tallest of our native trees. It is remarkable for the straightness of its trunk, which is often found a hundred feet high, entirely clear of limbs. The whole tree frequently attains an altitude of two hundred feet. It is the same as that known in England as Weymouth pine. In forests, all excepting the top branches decay early; and these, being above all other trees, make it conspicuous as far as it can be seen. Pine is of rapid growth, and, in favorable situations, increases an inch in diameter, and two feet in height, in a single year. The bark of trees which are less in diameter than fifteen inches is very smooth, and of a bottle-green; being, through the warm season, covered with an ashy gloss.

The color of the seasoned wood is a brownish white. A cubic foot weighs twenty-four pounds and three-quarters. Its decrease of dimension in seasoning is slightly more than spruce.* It has little tendency to warp or twist; and, for such parts of a frame as are liable to be exposed to dampness and continued wet, it is preferable to spruce. The wood being softer, it is more liable to indentation at the joints; and, being less stiff, it is not, for general purposes, entirely equal to spruce. As a whole, its average value for framing purposes may be considered as nine to ten.

* It is the generally received opinion of carpenters, that all wood is liable to some shrinkage in length; though, in most instances, it is hardly perceptible.

For finishing-lumber, it excels all others, and sustains the same relation to joinery that spruce does to carpentry. None is better calculated to withstand the effects of the sun and weather than this; for with the exercise of proper care in seasoning, and reasonable protection afterwards, it will retain its natural strength and vigor as long as the best of oak.

Carolina Pine (Pinus australis) is, in most respects, entirely unlike the wood last described; being very compact, and thoroughly saturated with a resin, or pitch, which is remarkable for its intense fragrance. It grows in great luxuriance in all our States south of Virginia, and is familiarly known at the north as southern pine. Timber of almost any reasonable length and dimensions may be easily obtained. This wood is seldom cut up into small joists; but, when not sawed into large framing-timber, it is used for planks and floor-boards; the solidity of the wood, and the fineness of its grain, making it of great value for the purpose last named.

In all dry situations, it is exceedingly durable; but, in wet or even damp places, it loses its vigor, and soon moulds and decays. Its tensive strength, compared with oak, is nearly equal; while its weight is much less. This quality, added to its peculiar stiffness and resilience, has of late years made it a rival of oak, where a lighter yet solid wood is required. It is, however, very brittle, and liable to fracture by a sudden blow or concussion; making it inferior to oak, where toughness is needed.

This wood, when newly planed, is a rich yellow; the resinous parts giving it a finely variegated appearance. The average weight of a cubic foot, when seasoned, is not far from thirty-eight pounds and a quarter. It decreases a fifth of its weight in seasoning, and a sixty-fifth of its dimensions; shrinking something more in the direction of its length than either of the other woods in common use.

Oak ( Quercus) is a wood, like all others, existing in many species. Only two, however, - those commonly known as white oak and yellow oak, - are in general use for building purposes. It is a native of temperate climates, and is found in great perfection and vigor in the United States, - from Virginia (the northern limit of the growth of Carolina pine) to the Canada line. The wood is very durable, when kept immersed in water; and, while remaining in a perfectly dry situation, it has lasted more than a thousand years. When subjected alternately to the action of water and air, together with more than ordinary warmth, it is subject to early decay. Oak-wood is hard, yet elastic and tough. Its texture is alternately porous and solid; the porous sections being the lighter colored portion of the annual ring. The wood of young trees is much tougher than that of old ones, and is more difficult to work. That of old ones is often quite brittle; while at the same time, in most other respects, it appears to retain its natural qualities. It is the case with oak as with all trees, - that the wood, taken from the body and large limbs, is stronger than that taken from the small branches. The sap is possessed of a peculiar odor and taste. It contains gallic acid; and, in consequence, turns black or purple, when brought in contact with iron.

The color of the wood is a whitish brown in the white species, and a yellowish brown in the yellow. A cubic foot, when dry, weighs forty-eight pounds. It shrinks, in seasoning, a thirty-sixth part of its dimensions, and loses a third of its weight.

For many purposes, - such as strengthening -pieces, keys, treenails, etc, - oak is indispensable; though of late years, as a general framing-timber, it has been little used. For the first two centuries after the settlement of this country, it was employed almost to the entire exclusion of other wood; but spruce and pine have gradually supplanted it, till now a new piece of oak-framing is but seldom seen. When used to any great extent, it is for open timber-roofs of churches, or something of the kind. The natural beauty of its selected wood for a rich finish-lumber, and its great strength and durability as a framing-timber, insure the usefulness and value of the "monarch of the forest."

In addition to the foregoing, the two next in value are those familiarly known as the black oak and the live oak. The former is nearly allied to the yellow oak; and is, in many respects, of equal value. Live oak is principally used in shipbuilding. The wood is nearly identical with white oak; but the nature and habits of the tree tend to produce only small and very crooked timber. For the various purposes, however, for which the timber is used, it is an important member of the Quercus family.

Hemlock {Canadensis) is often used in the cheaper kinds of carpentry. It is indigenous to nearly all places which are favorable to the production of spruce and the light pines. In dry situations, when the wood has been properly seasoned, and is carefully protected from the action of the sun, it may be considered as a fourth-rate wood. Its peculiar structure, tending to twistish or cleftish grain, makes it entirely unreliable for large timbers where either tensile or compressive strain is required. It decays quickly in damp situations; and, if exposed while in an unseasoned state, its heart-wood cleaves from the surrounding wood by the action of either sun or wind.

Considering these tendencies (existing even in the best specimens), it is usually cut into small studding-joists or common boards. Hemlock possesses one quality in common with oak and the other hard woods; viz., the tenacity with which it adheres to a nail. An ordinary tenpenny cut nail, if driven into the wood half its length, will part before it can be drawn out. This quality is one of its first recommendations for common or rough boarding, as it firmly holds the nails of shingling, slating, clapboarding, etc.

The sap is possessed of an intense and somewhat unpleasant odor. It is unfit for use while in an unseasoned state, as it corrodes iron immediately at the part where it begins to project from the wood. The color of the wood is a light brown; and a cubic foot, when dry, weighs twenty-seven pounds. It shrinks, in seasoning, a little less than spruce, and loses one-fourth of its weight.

Chestnut ( Castanet) is a wood of great value, and is in most respects nearly identical with oak, which it resembles in color, toughness, and solidity. It is a native of temperate regions, and is usually found growing side by side with its rival. For most purposes for which oak is used, chestnut is of equal value. While exceedingly durable in damp situations, it is equally so in those which are dry; and, in places partaking at times of both, it is preferable to oak. For posts set in the ground, it may be considered good for a service of forty years. Like oak, the grain of the wood is compact; and that of young trees is very tough and flexible: but old wood is liable to brittleness, appearing sound and healthy without, while within it is decayed and rotten. Chestnut contains one valuable quality not possessed by either of the other woods; namely, when once seasoned, it is but slightly susceptible of shrinking or swelling. The weight of a cubic foot of the wood, when perfectly seasoned, is forty-one pounds.