IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. In 1927 officials at Felt & Tarrant ...

This key-driven, non-printing adding machine is an early example of a Comptometer with a metal case. It has eight columns of plastickeys. The keys in the two rightmost columns, which represent cents, ...

The historical information is interesting, but more compelling is an archive of cheesy print ads for adding machines from the '30s to the '50s. And there's a Java applet that simulates the 1885 Felt & ...