Dalton Adding Machine

The Dalton Adding Machine is a ten-key mechanical calculator - considered one of if not the first of its kind - produced by the Dalton Adding Machine Company. It features ten white numerical keys and a few red function keys on the front surrounded by a dark green metal plate, an ink ribbon printer and paper rolls on top for displaying the current output of the calculator (the ribbon can print in either black or red ink), a crank handle on the right side for clearing the input. The calculator is enclosed in a thick cast iron enclosure, and features glass windows on the sides so users may view the inner mechanics working as they use the device.