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Burrough's adding machine. William Seward Burroughs (1857-98) was an American inventor. Originally a bank clerk, he invented a calculating machine and in 1886 founded the American Arithmometer Company, renamed the Burroughs Adding Machine Company in 1905. In 1925 Burroughs introduced the first portable adding machine. This transformed banking and accountancy by enabling calculation tasks to be completed faster and more accurately. The company name changed to Burroughs Corporation in 1953, and it merged with Sperry Inc to form Unisys Corporation in 1986.
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