1 Odhner Mechanical Calculator. Sweden, Circa 1920

Astonishing antique Odhner Arithmos Type 5 mechanical calculator in excellent condition, made in Sweden in 1920 and in very good working order. This machine is entirely original from the time and preserves all its original component parts and pieces. The gears, the lever and the mechanism boast a fluid and soft operation, so it is a real pleasure to use the calculator to perform the four basic arithmetical operations. The calculator stands on a sturdy solid-oak wooden base with milled edge, in good condition and with the original satin finish. The metal casing that covers and protects the mechanism bears a black-lacquered finish in really good condition. At the left front side of the calculator we can see the embossed manufacturers name, ORIGINAL ODHNER, and the model ARITHMOS. Engraved at the bottom left corner we can see the model number TYP 5, while at the back we find the serial number: Nº 41251. This antique Odhner Arithmos Type 5 mechanical calculator is a survivor from the time of turn-of-the-century mathematical machines. It still arouses admiration for its precision and great working order.Odhners Calculators History The history of Odhner calculators actually describes the first times of all mechanical calculators. W. T. Odhner was a Swedish engineer and entrepreneur who invented his first arithmometer (or pinwheel calculator) in Rusia in 1871. Odhner was repairing a Thomas arithmometer, the only mechanical calculator in production at the time, and decided to replace its heavy Leibniz cylinder by a lighter pinwheel disk. So he created the first modern calculator whose design was imitated and reproduced countless times during the 20th century. Odhner produced and sold his owns calculators, but after the Russian revolution of 1917 he moved to Switzerland and opened a new factory where he manufactured his arithmometers under the Original Odhner commercial name.