The basic operating principles of mechanical calculators changed little from the end of the 19th century to their obsolescence in the 1970s, though there were.
Results 1 - 48 of 58 Original Odhner, Vintage mechanical Calculator, pin wheel. Vintage German Thales Patent Mechanical Calculator Arithmometer Adding.
A mechanical calculator, or calculating machine, is a mechanical device used to perform the time and mental effort in arithmetical computations, and to eliminate human liability to error, is probably as old as the science of arithmetic itself.
Vintage Mechanical Calculator Made in Germany in 30s Working Pin-wheel RARE Vintage Totaldator - 100 Year Mechanical Calendar Calculator, Red color -.
antique American made mechanical calculator pinwheel calculator rapid calculator by whimsicalbazaar, $425.00.