McCormick, Cyrus Hall

1809–1884
Inventor

Invented the horse-drawn mechanical reaper in 1831. He was 22. Three years later, he patented it, but he worked another six years to improve it before it first went on sale in 1840.

With his reaper, farmers harvested five times more wheat in a single day than they could with human labor. By 1859, it was estimated that the McCormick reaper contributed $55 million annually to the gross national product.