Adding Machines
An adding machine is a type of mechanical or electromechanical calculator, usually used in bookkeeping. With the advent of the personal computer adding machines have largely fallen out of use.
Early mechanical calculators were developed by Wilhelm Schickard, Blaise Pascal and Gottfried Wilhelm von Leibniz. Calculating machines did not gain widespread use, however, until the 1880s when machines were introduced by William Seward Burroughs I (Burroughs Adding Machine Company) and Dorr Felt (Felt & Tarrant Manufacturing Company).
