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Unical Correntator

Correntator set to add

Correntator set to subtract

• Type: Adding Machine
• Size: 2.5 x 4 in / 7 x 10.5 cm
• Material: Brass

With paperboard faux leather slip cover and instructions for a different model. Made in Switzerland in the late 1930s following a German design of a decade earlier. A hinged panel in the center of the unit allows display of either of a single set of guide digits for either addition or subtraction. Clearing handle at top, and hollow brass stylus clipped to one side. Unit has eight input columns and a nine-digit output display. This unit is for decimalized money; a unit was available for pounds/shillings/pence (this is the unit I have the instruction pamphlet for).

Gift of David and Gayle Teller.