General Interest

Unbound Spiral: Curta

March 4, 2003 05:37 PM

The Curta Calculator circa 1947.


Major components of the machine are: the carriage that can be moved to Six different positions for multiplication and division; the number transmission mechanism; the ten's carry mechanism; and the result and counter dials.

This precision calculator that weighs eight oz performs addition, subtraction, multiplication, division, squaring, cubing, and square root operations. The number set is transferred to the result dial once for each turn of the operating handle while the revolution counter records the number of these turns.

Automatic devices prevent errors from mishandling. For instance, if one turn too many is made, it can be eliminated by a turn of the handle with the axis in the other position (subtracting instead of adding).

Capacity of the machine is 8x6x11 places. Eight place digits can be set for addition or subtraction; six place multipliers can be used; and maximum results of eleven places can be obtained.