The seventh patent issued by the United States, to Samuel Mulliken of Philadelphia, was for a threshing machine.

The portable horse-power treadmill, invented in 1830 by Hiram A.and John A.Pitts of Winthrop, Maine, was presently coupled with a thresher, or "separator," and this outfit, with its men and horses, moving from farm to farm, soon became an autumn feature of every neighborhood.

The treadmill was later on succeeded--by the traction engine, and the apparatus now in common use is an engine which draws the greatly improved threshing machine from farm to farm, and when the destination is reached, furnishes the power to drive the thresher.

Many of these engines are adapted to the use of straw as fuel.
Another development was the combination harvester and thresher used on the larger farms of the West.

This machine does not cut the wheat close to the ground, but the cutter-bar, over twenty-five feet in length, takes off the heads.