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V. WHEN A TREE IS LUMBER
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Have you a wooden top to spin? As it spins, it stands upright on its tip. But the first time your top spun was when it was made. It was held between two pivots and whirled side ways. Spinning wheels are used in shaping rounded articles of wood, just as they are used in shaping clay. The clay worker’s whirling table is called the potter’s wheel, but the wood worker’s spinning wheel is called a lathe. In every house are examples of the wood turner’s work—in chair and table legs, in the spindles of stair and porch railings, and in the supporting columns of arches and mantels; yes, and in croquet balls and mallets and tenpins.

The very first lathe that men made was like a top in one thing. It was kept spinning with a string. One end of the string was fastened toa pole near the ceiling. The other end was wrapped around the block of wood that was to be shaped, and tied to a treadle. The treadle was kept going by the workman’s foot, just as your mama runs her sewing machine. The block of wood to be turned was clamped between two pivots and whirled with the wheel. As the block whirled toward him the workman pressed the sharp blade of a chisel against it and cut the wood away.

The very simplest of old wood turning hand machines were called lathes. We do not know whether the word came from lath, the light pole that held the string, or from an old word that meant frame to hold things, or from lade, "to load;" for the lathe is a frame, and it carries the load or the weight of the wood that is being shaped. The machine lathe of today, operated by steam power and working automatically, or self-regulatingly, is made on the same principles as the treadle spinners of the earliest woodworkers.

The pole and the wheel and string are gone, of course. In their place are cone-shaped pulleys and flying leather belts. Cone-shaped pulleys are several wheels, each one smaller than the last, welded together into one, and making a stepped cone. By shifting the belt from one wheel of the pulley to another, the workman can turn on slow or rapid power to suit the hard or soft wood he is carving, and