Addiator
1920 · Slide Adder · Work 436 of 1,871
A pocket adding device in a nickel-plated sleeve, parallel toothed slots down the face with a column of the digits 0 to 9 beside each slot, a small clearing loop of wire folded at the top, a row of small result windows across the top, each window showing the single digit 0, a leather case lying open beside it, every other surface plain bright nickel, the sleeve lettered "Addiator", standing on a dark baize-covered table before a deep neutral background, a single raking light from the left raking across the toothed slots.
- What it was used for
- A flat metal device for the pocket, worked with a stylus, addition on one face and subtraction on the other. The special versions show what it was used for: models for pounds, shillings and pence, the Quantotar for British weights, the Hexadat from 1971 to 1976 for programmers. For the Kaufhof department stores the firm built an enciphering version between 1961 and 1970, used to keep daily takings secret from its own staff; the Crypto Museum puts that at some 3,000 to 5,000 units. According to the Crypto Museum, in 1960 the firm exported to 92 countries, most devices going to the USA.
- What was new
- What was new was not the principle but the form: addition and subtraction on the front and back of a single flat case; Kübler filed this reverse side with subtraction slots for a patent in 1919 (DE 367,599). The hook-shaped slot for the carry goes back to Kummer in the 1840s. Nor does the invention of this device belong to the firm's founder alone: Carl Kübler, who founded the firm on 13 February 1920, bought the MEUM slide adder that Otto Meuter had been making since 1918, together with its utility patent, and Meuter then worked as a designer in Kübler's factory. The number: about one million standard units between 1930 and 1975. The end came from the same direction as the last customer: production ran out in 1974, the firm was dissolved in 1975, and according to Scherphuis the Hexadat for programmers was still on sale until 1976.