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The operation by which grain is separated from the straw. This operation is performed in various ways, as by the feet of animals, by a flail, or by a thrashing-machine. The first mode was that employed in the ages of antiquity, and it is still practiced in the south of Europe, and in Persia and India. Oxen were generally employed for this purpose, either alone or with the addition of a kind of roller studded with iron knots, which the oxen dragged over the grain-sheaves, which latter were spread on a circular floor in the form of a circle, the ends containing the grain being placed towards the centre. Thrashing by the flail is still practiced in various parts of Europe, but thrashing-machines, which effect a great saving in time and labor to the farmer in this country, have been very extensively introduced.