Definition:

Cyrus McCormick, a blacksmith in Virginia, developed the first practical mechanical reaper to harvest grain in 1831. His father had earlier worked on the device but abandoned it, and Cyrus eventually took up the project and incorporated innovative features.

McCormick at first only sold his machines to local farmers, but ultimately started a factory in Chicago. The McCormick Reaper revolutionized agriculture, making it possible to harvest large areas of grain much faster than could have been done by men wielding scythes.

The earliest horse-drawn reapers made by McCormick cut the grain, which fell onto a platform so it could be raked up by a man walking alongside the machine. Later models consistently added practical features, and McCormick's farm machinery business grew steadily.

A model of the McCormick reaper was shown at the Great Exhibition of 1851 in London, and was the source of much curiosity. McCormick's machine, during a competition held at an English farm in July 1851, outperformed a British-made reaper. When the McCormick reaper was returned to the Crystal Palace, the site of the Great Exhibition, curious crowds came to see the innovative machine from America.

Workers at McCormick's factory struck in 1886, and events surrounding the strike led to the Haymarket Riot, a watershed event in American labor history.