Searching for a Solution: 1820–1851[edit]
Detail of an arithmometer built before 1851. The one-digit multiplier cursor (ivory top) is the leftmost cursor
The arithmometers of this period were four-operation machines ; a multiplicand inscribed on the input sliders could be multiplied by a single-digit multiplier by simply pulling on a ribbon (quickly replaced by a crank handle). It was a complicated design[5] and very few machines were built. Additionally, no machines were built between 1822 and 1844.
This hiatus of 22 years coincides almost exactly with the period of time during which the British government financed the design of Charles Babbage's difference engine, which on paper was far more sophisticated than the arithmometer. It could not be built with the technology of that time, however.[6]
In 1844 Thomas reintroduced his machine at the Exposition des Produits de l'Industrie Française in the newly created category of Miscellaneous measuring tools, counters and calculating machines but only received an honorable mention.[7]
He restarted the development of the machine in 1848. In 1850, as part of a marketing effort, Thomas built a few machines with exquisite Boulle marquetry boxes that he gave to the crown heads of Europe. He filed two patents and two patents of addition in between 1849 and 1851.
Creating an industry: 1851–1887[edit]