Dorr Felt

Dorr Eugene Felt was an American inventor and industrialist who was known for having invented the Comptometer, an early computing device, and the Comptograph, the first printing adding machine. The Felt amp Tarrant Manufacturing Company that he cofounded with Robert Tarrant on January 25, 1889 remained a major player in the calculator industry until the mid1970s.

Dorr E. Felt was born in Beloit, Wisconsin where he grew up on the family farm and which he left at ageto seek employment. His father, Eugene K. Felt, was a member of the Wisconsin State Assembly.

Source: Wikipedia