The adding machine fraternity at St. Louis: creating a center of invention, 1880-1920
Peggy Aldrich Kidwell · IEEE Annals of the History of Computing · 2000
Between 1880 and 1920, several inventors in St. Louis, Missouri, made pioneering contributions to the development of commercial adding machines. The inventions of Frank S. Baldwin, William S. Burroughs, the brothers William W. and Hubert H. Hopkins, and their associates did much to make mechanical arithmetic commonplace in US business.