THOMAS de COLMAR, Charles Xavier
Type: T1865B, 58 x 18 x 6 cm, brass instruments in wooden case, numbered: no. 2232 (top cover missing, the glass cranck handle is detached but present, sm. crack in glass cover at lower left).
The world's first produced and marketed mechanical calculator. Thomas' original pattent for the machine was filed already in 1821, but he spent the next 30 years perfecting its design. About 5.500 machines were produced between 1852 and 1915. Its sturdy design gave it a strong reputation for reliability and accuracy. For forty years, from 1851 to 1890, the arithmometer was the only type of mechanical calculator in commercial production, and it was sold all over the world to shopkeepers, merchants, engineers, banks, governments and other professionals who daily used arithemtics. The arithmometer enabled people to make fractions, additions, divisions, substractions and multiplications. The machine improved upon the previous mechanical calculators of Blaise Pascal (1642) and applied the Leibniz wheel (1673) as a calculating device. The upper part of the calculator contains the accumulator dials that display the results with a possibilty up to 16 digits. This enabled calculations up to one quadrillion. For his invention of the arithmometer, Thomas (1785-1870) was made Chevalier of the Légion d'honneur. During the early part of manufacturing, Thomas differentiated machines by capacity and therefore gave the same serial number to machines of different capacities. He corrected this in 1863, giving every machine its own unique serial number starting with a serial number of 500. From 1863 to 1907 the serial numbers were consecutive (from 500 to 4000). This model was produced in 1886 and bears serial number 2232. Arithmometers are extremely rare. Only one other arithmometer is recorded in a Belgian collection (ULB). As far a we could determine the machine still functions perfectly.
Première machine à calculer produite en série et commercialisée, présentée pour la première fois en 1821. Elle restera pendant des dizaines d'années la seule machine capable de faire les quatre opérations. D'après le rapport publié à l'époque de son invention, elle fut jugée réellement pratique et supérieure à toutes les machines présentées au public depuis celle de l'illustre Blaise Pascal en 1642. Utilisée dans divers domaines comme les banques, les assurances, le cadastres, les statistiques, elle fut vendue à environ 5.500 exemplaires entre 1851 et 1915.
Ref. L. De Brabandere, Calculus. Les Machines du calcul non électriques. Liège, 1994, pp. 117-118. - www.arithmometre.org.
€ 1.000 / 1.500