Invented by Leonardo Torres in 1920, the Torres calculating machine is a machine that solves essential addition, subtraction, multiplication, and division problems using a simple manner. It was a ...
IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. This full-keyboard, non-printing ...
Most early calculating machines carried out multiplication as a form of repeated addition. To multiply, say, by thirteen, one set the carriage at its rightmost position, turned the operating crank ...