. Wood; a manual of the natural history and industrial applications of the timbers of commerce. Wood; Timber. es OF WOOD IN GENERAL bark and sapwood of the Teak three years before it is intended to fell it. This stoppage of all ascending sap kills the tree in a few weeks: the heat of the climate helps the seasoning process; and, as usually about a year elapses between the felHng of the timber and its delivery in England, it is then fit for immediate use. It is recommended that the dense Australian timbers should, hke Teak, be ringed while standing. This should be done a year or more before fel
. Wood; a manual of the natural history and industrial applications of the timbers of commerce. Wood; Timber. es OF WOOD IN GENERAL bark and sapwood of the Teak three years before it is intended to fell it. This stoppage of all ascending sap kills the tree in a few weeks: the heat of the climate helps the seasoning process; and, as usually about a year elapses between the felHng of the timber and its delivery in England, it is then fit for immediate use. It is recommended that the dense Australian timbers should, hke Teak, be ringed while standing. This should be done a year or more before felling, and between April and August, when the sap is quiescent. The tree is most thoroughly drained of its sap when thus left vertical. It has, however, been objected to this process that it causes or intensifies heart-shake, and, by drying the wood too rapidly, renders it brittle and inelastic. Seasoning of some kind is, in all other cases, rendered imperative by the changes in volume, irregular shrinkage, or warping, that all green woods undergo under the influence of changes in atmospheric temperature and moisture, especially in their cross sections. So important is it to avoid this warping in furniture, wheelwright's. Fia. 42.—Plank iDadly laid, witli the mside, or inner rmgs, upward. (After Laslett) work, etc., that it is a common practice to block out work roughly and let it season a little longer before finishing. Seasoning is ordinarily understood to mean drying; but, in addition to the evaporation of water, it impHes other changes, such as the drying out or partial decomposition of the albuminous sub- stances in the wood, rendering it more permeable and less ferment- able. The strength of many woods is nearly doubled by seasoning, hence it is very thriftless to use it in a green state ; as it is then not only weaker, but is liable to continual change of bulk and form. The longitudinal fibres of the wood being, as it were, bound together by the radiating pith-rays, as
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