• Willgodt Odhner (1845-1903) was a young Swedish engineer working in Ludvig Nobel’s (older brother of Alfred Nobel) machine factory in St. Petersburg. In 1875 he finished the first prototype of his 8-digit arithmometer. It was a refined and simpler version of the Thomas calculating machine which is considered as the first commercially successful practical calculator to be used in office environment. He convinced his boss to manufacture and sell 14 calculating machines. After the initial 14 calculators Nobel lost his interest in this project and Odhner continued the venture on his own. After his death in 1903 his sons continued the business until 1918 when the factory was nationalized and closed during the Russian revolution. By that time Odhner was the best known calculator brand and there were many imitations like Brunsviga, Thales and Facit in the market. The family moved to Sweden and continued manufacturing calculators until 1970’s under the “Original Odhner” name.
    Georgi Dalaokv’s History of Computers - Biography of Willgodt Odhner
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