The Burroughs Corporation was a major manufacturer of business equipment. Founded in 1886 as the American Arithometer Company. After the 1986 merger with Sperry-Univac it was renamed Unisys. At its start, the Burroughs Corp. produced mechanical adding machines and later programmable ledgers and computers.This is a Burroughs Class 3 adding machine. This particular machine was introduced in 1911 and advertised between 1913 and 1927 (Office Museum.com). The plate on lower front of machine has the number: 3-884135. There is a keyhole on the plate for accessing and changing the ribbon.