. Seasoning of wood; a treatise on the natural and artificial processes employed in the preparation of lumber for manufacture . he mirrors,on the radial section. In additionto these coarse rays, there is alsoa large number of small pith rays,which can be seen only when mag-nified. On the whole, the pithrays form a much larger part ofthe wood than might be specimens of good white oak ithas been found that they formabout sixteen to twenty-five percent of the wood. Minute Structure If a well-smoothed thin disk orcross-section of oak (say one-six-teenth inch thick) is held up tothe lig
. Seasoning of wood; a treatise on the natural and artificial processes employed in the preparation of lumber for manufacture . he mirrors,on the radial section. In additionto these coarse rays, there is alsoa large number of small pith rays,which can be seen only when mag-nified. On the whole, the pithrays form a much larger part ofthe wood than might be specimens of good white oak ithas been found that they formabout sixteen to twenty-five percent of the wood. Minute Structure If a well-smoothed thin disk orcross-section of oak (say one-six-teenth inch thick) is held up tothe light, it looks very much likea sieve, the pores or vessels ap-pearing as clean-cut holes. Thec, a single joint or cell of spring-wood and gray patches areLdlngSnto ItTZler ^^eu to be quite porous, but theand lower neighbors; d, firm bodies of fibres between themtracheid; e, wood fibre are dense and opaque. Examined^^^^^^- with a magnifier it will be noticed that there is no such regularity of arrangement in straightrows as is conspicuous in pine. On the contrary, greatirregularity prevails. At the same time, while the pores. Fig. 8. Isolated Fibres andCells, a, four cells ofwood, parenchyma; b,two cells from a pith ray; BROAD-LEAVED TREES 35 are as large as, pin holes, the cells of the denser wood,unlike those of pine wood, are too small to be distin-guished. Studied with the microscope, each vessel isfound to be a vertical row of a great number of short,wide tubes, joined end to end (see Fig. 8, c). Theporous spring-wood and radial gray tracts are partlycomposed of smaller vessels, but chiefly of tr,acheids, likethose of pine, and of shorter cells, the wood parenchyma,resembling the cells of the medullary rays. These latter,
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyorkdvannostran
