The Arithmometer was the first commercially mass-produced calculating device. Patented in France by Thomas de Colmar in 1820 and manufactured from 1851 to 1915, the device could add and subtract two numbers directly and could perform long multiplications and divisions.
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https://www.homemadetools.net/forum/...896#post108875
https://www.homemadetools.net/forum/...6452#post83701
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https://www.homemadetools.net/forum/...166#post115788
