Recent Acquisitions

Trinks Brunsviga MR   Brunsviga Braunschweig, 1920. Serial 38930. Sold by The Muldivo Calculating Machine Co. Ltd., London 1921. Very rare collector's item. The machine is mounted on a firm wooden bottom and can be protected and locked by a wooden case. The mechanism of this model was improved by the German engineer Franz Trinks. This pinwheel Odhner-like machine still functions perfectly.

PRODUX Adding Machine     Meuter's calculators became successful under the name PRODUX. After worldwar 2 the company split: In West-Germany PRODUX production continued and under the East-German communist system RECORD calculators were produced until 1988. This little pocket-machine (15x8 cm.) is for adding (downward sliding) and subracting (upward sliding) only.

Otis King's Pocket Calculator Cylindrical slide rule with helical scales, made in England by Carbic Ltd., London 1921-1972. Suitable for general and specialized arithmetic. The device has a telescopic design and consists of four parts: holder, bottom scale, movable cursor and top scale. Rather easy to operate for those who are (were) able to work with normal lineal slide rules.

CURTA Type II      Small, hand-cranked mechanical calculator. Model 1 was introduced in 1948. It had a brilliantly compact design, a small cylinder that fit in the palm of the hand.  The Curta's design is a variant of Gottfried Leibniz's Arithmometer, accumulating values on cogs, which are added or complemented by a stepped drum mechanism. Invented by Curt Herzstark while he was a prisoner in the Buchenwald concentration camp.

COMPTATOR     Handheld Chain Adder - Hans Sabielny Dresden, Germany 1922. Very robust metal and rather heavy (600 g) adding machine. A metal stylus is needed to drag the racks or chains downwards in order to achieve adding and automatic cary. It is a refinement of the Rapid Computor Adding Machine. Subtraction is implemented by using the complementary method. The right hand lever is used for zeroing the display.

Maximator - S Multi-DIVI The front of the first adder is used for adding, while the other (flippable) side is used for subtraction. The first adder can be removed from the metal case. The calculating device is a set of sliding digits embedded in a metal frame. The case that holds both slide adders measures 19x15x9 cm. One side of the stylus is for sliding up and down and to 'carry'. The other side is a pencil for making notes on paper. The adders can be zeroed by pulling the handle at the top of the machine.

Correntator CBR   Antique but smart and handy (for that time) handheld machine for addition and subtraction. CBR stands for Continentale Büro Reform. In the middle of the tiny brass machine is a little metal flap can be turned up and down to switch between the two operating modes: add and subtract.