Manufacturer and Builder 10, 1874
The figure of wood depends more upon the particular mixings and directions of the fibers, than upon any difference of color. If a tree were found formed of merely circular rings, like the section of an orange, filled with layers of peel instead of pulp, the horizontal section would exhibit circles; the vertical, parallel straight lines; and the oblique section, parts of ovals; but few, if any, trees are to be found either exactly perpendicular or straight; and therefore, although the three natural sections have a general disposition to the figures described, every little bend and twist in the tree disturbs the regularity of the fiber, and adds to the variety and ornamentation of the wood. A perpendicular cut through the heart of the tree is the hardest and most diversified, because in it occurs the most profuse mixture and density of the fiber, the first and the last in point of age being presented in the same plank, but the density and diversity lessen as the board is cut further away from the axis.
Curls are formed by the confused filling in of the space between the forks of the branches. The beautiful figure thus induced causes a log, say of mahogany, to be valuable in proportion to the number of curls it contains. There is great competition at public auctions for such logs, and prices which seem astonishingly large are sometimes given for a log known by judges to contain several fine curls. Occasionally some disappointment may be experienced when the log is opened, but not often. The curl generally shows itself on the outside, where it can be seen, and there is always the possibility of there being interior ones as well, which do not show on the surface.
Figure is also produced as follows: The germs of the primary branches are set at an early period of the growth of the parent stem; and thus give rise to knots. But many fail to penetrate to the exterior, and are covered over by the more vigorous deposition of the annual rings. Each branch is a miniature tree down to the smallest twig, and this process goes on in each individual branch just as in the trunk. These knots produce figure in the following manner: When the germ succeeds in forcing its way to the surface, the future rings of the trunk bend and turn aside when they encounter the knot, and in the softer wood do not unite with it. This accounts for whitewood knots being so liable to fall out. The turpentine in other sorts of woods acts as a sort of cement, and keeps the knot in its place. The hardness of knots is due to the close grouping of the fibers, and to their compression by the surrounding wood, which itself is allowed expansion by the yielding nature of the bark. The same operation goes on beneath the ground in tire roots of a tree, and splendid furniture veneer is obtained from soars descriptions.
The bird's-eye maple has internal points or spines on the inside of the bark, which penetrate the wood and make irregular indentations. These cause tire peculiar appearance which is so much prized, and from which the wood takes its name.
In woods the figure of which resembles the ripple marks of the sea on fine sand, such as satinwood, sycasnore, mahogany, ash, etc., the figure is produced by the serpentine form of the grain. The fibers of all such pieces are wavy on the face at right angles to that on which the ripple is observed, if not on both faces, those parts of the wood which happen to receive the light, being brightest. Woods having the silver grain, or, as called by botanists, "medullary plates or rays," possess another sort of adornment, namely, a sort of dappled effect, or an effect similar to that produced on silk by threads running crosswise to those longitudinally disposed. English oak, Riga and Dutch wainscot logs, Austrian wainscot, etc., have this peculiarity. In the oak plank the principal streaks or lines are the edges of the annual rings, which show, as usual, parallel lines (more or less waved) from the curvature of the tree or the neighboring knots and branches. The damask pencillings, or broad curly veins and stripes, are caused by groups of the medallary rays, which undulate in layers from the margin to the center of the tree, and creep in betwixt the longitudinal fibers. Had the fibers of trees been arranged with the uniformity and exactitude of a piece of plain cloth, they would have shown an even uninterrupted color; but being arranged by nature in irregular curved lines, almost every intersection of them by the hand of man partly removes some, and exposes others, thus causing a great variety of figure. To such a boundless extent do the changes caused by tints, fibers, curls, knots, etc., exist that the cabinetmaker scarcely ever seeks to match any pieces of wood for the purpose of causing uniformity of figure in the article he is making, and, indeed, diversity is more pleasing to the eye than uniformity would be, if it were practicable.
As regards color, some woods are nearly uniform, and some have several shades of the same hue, or of two or three different colors. In the horizontal section of such woods, the tree seems to have clothed itself with different coats of various colors — such as tulipwood, kingwood, zebrawood and rosewood. In the ordinary planks these markings get drawn out into stripes, bands, and patches, or wavy figures of the most beautiful or grotesque character. Woods variegated both in grain and color are snore generally employed for objects with smooth surfaces, such as cabinet work. Such are Amboyna, kingwood, some mahogany, maple, partridge, rose, satin, snake, tulip, and zebrawood. Beautiful specimens of marquetry which we have recently seen, aptly illustrate the use of such wood for tire purpose of ornamentation, and they also prove that they are out of place in other than smooth surfaces, for the same style of work in moldings has a decidedly inferior effect.
The colors of fancy woods are not liable to fade by exposure to light, tulipwood being an exception; bunt age of course darkens them and mellows the general effect. But the whitest of varnishes should be applied, or the natural tint is liable to be spoiled.
The rich greenish-brown of walnut is much esteemed, and especially for piano-forte cases. The large makers own stocks of this and other fancy woods to an extent few have any idea of. The rich deep orange of Spanish mahogany makes beautiful tables and counter tops, and its large square surface makes it peculiarly adapted to either uses. Honduras, of a brownish tint, is used for all kinds of superior cabinetwork, while oak is principally employed in those parts of housebuilding where durability is a necessity. Wainscot is preferred for cabinetwork, and the Austrian. has lately come into deserved favor. Pitch pine, too, is pleasing both as to color and figure; rosewood, with its rich tints, is not so much used as formerly. The color of wood, when in the log, may readily be ascertained by scraping the outer rind, when the figure may also be guessed at with a tolerable degree of accuracy; but to arrive at any degree of perfection as a judge requires a very long practice, and it is almost impossible to frame rules in writing, any one of which would not be liable to numerous and bewildering exceptions
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