Brunsviga - 20 century calculator ⌨️👨🏼‍💻

The Brunsviga Nova 13, Olympia Werke AG, Wilhemshaven, circa 1920, entirely mechanical, typical of computing equipment used at Columbia University in the mid-1920s. Brunsviga and Millionaire calculators are listed in the 1924-1925 Columbia University Catalogue in the Social Science section (the specific Brunsviga models are not stated but the Nova 13 is a likely candidate).

An adding machine could do only sums. A calculator could also multiply and possibly divide (of course later calculators could do more than that). Multiplication was performed by entering the multiplicand and then turning the crank "multiplier" times (or vice-versa). Models like the Brunsviga allowed certain crank-saving techniques.
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