Comptometer Model C Section

Description:

This model has one column of nine white plastic keys and a second column of nine black plastic keys. Digits and complementary digits are indicated on the keys. Keys for odd digits are concave, and those for even digits are flat. The mechanism is of steel and the 3 numeral wheels have a black plastic rim. There are two subtraction levers at the base of the keyboard and a crank on the right. The entire model rests on a wooden base. There is no cover. The model was used as reference by Dorr E. Felt and J. A. V. Turck in developing the mechanism for production of the Model C Comptometer.

Reference:

Felt & Tarrant, Accession Journal, 1991.3107.06.