The faces of most of the boards are cut nearly parallel to the medullary rays, these rays come to the surface at small angles and make the beautiful spotting often seen in oak and sycamore. Quarter-sawed boards do not warp or twist as much as the plain sawed because the annual rings are perpendicular to the face.
124. Waste.
—Attached to every sawmill will be found tower-like structures from the tops of which smoke issues, [Fig. 216]. These are called burners and into them are thrown thousands of tons of waste wood. Waste wood is used as fuel for the engines and for many other purposes but there still remains much that is burned as the cheapest way to get rid of it.
Fig. 216.
A MODERN SAWMILL, SHOWING REFUSE BURNER.
125. Lumber Transportation.
—Sawed lumber is transported to the yards in various ways. It is loaded and carried by boats, by cars, and in some places is floated to its destination in narrow wooden troughs called flumes.
On the Pacific coast mills are frequently built out over the water on piles so that the lumber is loaded directly from the saws. Frequently lumber is formed into rafts and towed to its destination in a manner similar to that of the log rafts of the Pacific.
126. Seasoning.
—There are two methods of drying wood, in common use: air drying and kiln-drying.