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American - circa 1913
"The American Can Company of Chicago, Illinois machines are distinguished by the setting mechanism, which requires the operator to position stepped finger supports. The accuracy of the entry may be checked before pulling the crank to commit the value to the register. The results are then displayed on dials above the 'keyboard'. By 1914, this machine had been introduced into 'all the most important European countries'."
Source: Dr. Tim Bergin American University Computer History Museum - Mechanical Computing

X-Number World of Calculators