Dorr Felt  Dorr Eugene Felt (March 18, 1862 – August 7, 1930) 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 & Tarrant Manufacturing Company" that he co-founded with Robert Tarrant on January 25, 1889 remained a major player in the calculator industry until the mid-1970s. Dorr E. Felt was born in Beloit, Wisconsin where he grew up on the family farm and which he left at age 14 to seek employment. His father, Eugene K. Felt, was a member of the Wisconsin State Assembly. At 16, "his bent of mind, leaning towards mechanics, led him to seek work in a machine shop in Beloit where he found his first employment in the spring of 1878." At 18, he started to learn French and eventually spoke it fluently. In early 1882, at age 20, he came to Chicago and worked as foreman of a rolling mill that had a daily output valued at $2,000. In that time he began his work on Comptometer. During the US Thanksgiving holidays of 1884 he decided to build the prototype of a new calculating machine that he had invented. Because of his limited amount of money, he used a macaroni box for the outside box, and skewers, staples and rubber bands for the mechanism inside. It was finished soon after New Year's Day, 1885. Felt brought his idea to Chicago businessman Robert Tarrant. They signed a partnership contract on November 28, 1887, and incorporated the "Felt & Tarrant Manufacturing Company" on January 25, 1889. Felt later went on to invent more devices and acquired 46 domestic patents and 25 foreign ones. The original "macaroni box" prototype and the first Comptograph ever sold are now part of the Smithsonian Museum collection of antique calculators. He was married to Agnes McNulty in 1891 and the couple had four daughters together. Felt was awarded the John Scott Medal of The Franklin Institute in 1889. Dorr Felt also was the first ambassador for the Department of Commerce formed to study labor abroad after World War I. He was an excellent photographer, and many of his war-time and post-war time photos were used by the government. Dorr traveled the world and loved learning. He made his home in Chicago and summered in Laketown Township, Michigan, where the Dorr E. Felt Mansion is registered on the list of National Historic Places.