Threshing, the process whereby ripened grain is removed from the chaff—the husks and straw--is done after grain has been harvested. The earliest method of threshing was to pound the stalks in order to loosen the grains. Grain could be flailed on barn floors with flail s made of wooden bars, or swingles, fastened loosely to a handle. The grain was manually beaten loose. An early labor-saving threshing device was the Egyptian charantz, a sled-like device that threshed the grain with spiked cylinders that turned as it was pulled. The Hebrews had a similar device called a moreg. The early Japanese used flails equipped with iron or wooded teeth that stripped the grain from the stalk.

Another early threshing method was treading. Horses, and sometimes oxen, were forced to walk through the grain. The force of their weight loosened the grain. Although a great deal...