Page:Cassells' Carpentry and Joinery.djvu/43

Rh they present the beautiful figured appearance called silver-grain or felt, as illustrated by the longitudinal section (Fig. 126). To produce this effect, the timber must be sawn in the radial planes of the medullary rays, or slightly oblique to them. As already mentioned, the wood is composed of bundles of cellular tubes, which serve to convey the required nourishment from the earth to the leaves. Fig. 125 shows the cross section with the annual rings and the medullary rays, the sapwood being on the outside and the remainder heartwood. , Fig. 126, shows the longitudinal section





through the centre of the tree where the flower or silver-grain (that is, the medullary rays in elevation) is marked, together with the edges of the annual rings. , Fig. 125, shows a longitudinal section nearer to the bark, where the graining is formed by the