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 When any tree is first cut it is "green," or full of sap. To be useful for lumber it must be seasoned, or dried. Sometimes, and with some kinds, as with teak, me tree is girdled by cutting a belt all around it and allowing it to die standing. A log is never allowed to lie on moist ground by good lumbermen, for then it would be attacked by insects and fungi, or toad-stool-like growths, and would quickly begin to decay. In our country logs are usually hurried to a saw mill and squared. That is, the bark is sawed away on four sides. Oaks are often quartered, that is, cut across the middle both ways, making four logs. These logs are then piled up in lumber yards for open air drying, or they are sawed into planks and then seasoned.

Two kinds of saws are used in saw mills—the circular and the gang saw. The circular saw is a big toothed steel plate that revolves, cutting through a log as it turns. The gang saw is made up of a number of blade saws set in a frame like the blades of a safety razor. The " gang " goes through a log and cuts it into planks in one journey. The barrel saw used in cooper shops earns its name twice. It is shaped like a barrel stave and is used for cutting the curved staves of barrels, kegs, hogsheads and.water pails. The band saw of furniture factories is really a flexible band or belt of steel, that turns over pulleys like a leather belt. It is used for scroll sawing, in making such things as the open—work music racks on pianos.

And now, here is something very odd about saws. When men first began to make saws they set flint stone teeth into wooden blades. When they learned to make bronze, saw blades were cast or molded with toothed edges. Steel saws had the teeth cut on the blades. But it was discovered that the teeth wore and were sharpened away very fast, so the saw became constantly smaller and, by and by, useless, although the blade was perfectly good. Steel was made harder and harder, but still saw—teeth broke and wore away, in having, to go buzz-zipping through hardwood logs. Then saw makers went back to the old, old idea of false teeth for saws. The teeth are made separately and set into the blade. When a tooth breaks or wears out a new one goes in. Doesn’t it seem strange that our latest saw goes back, for its new idea, to the flint-toothed wooden blade of primitive people?

Have you ever seen a lumber yard? The planks are piled up in tall stacks, but every plank is separated from every other one by a cross-piece. This is to allow the air to get to every surface to season