03.0

//Source(s): A History Of Computing Technology by Michael R. Williams; Prentice-Hall, 1985. LC#QA71.W66 1985// (((I don't believe this qualifies as an outright *medium*, but the Arithmometer was a commercial mainstay of 19th century calculation. Arithmometers were in fact produced up to World War I. This indicates the ever-increasing public demand for calculating machines during the early industrial era.))) page 150-151 THOMAS ARITHMOMETER: The first commercially produced calculating machine, produced by Charles Xavier Thomas de Colmar in France. Based on Leibniz's calculating machine, the device utilized stepped drum gears for calculation. However, the major innovation was to reverse the operating function in the result registers (up to sixteen digits), allowing for reliable and stable calculation over extended periods of time without gear re-alignment. The machine took up an entire desk and required two people to carry it. It spurred on many rivals, eventually leading to quite sophisticated calculating machines that overcame the pitfalls of the stepped-drum design. Thomas received France's Chevalier of the Legion of Honor for the product. Brad
 * Dead medium: C. X. Thomas de Colmar's Arithmometer**
 * From: boneill@allinux1.alliance.net  (Bradley O'Neill)**