Odhner Arithmometer

Odhner, W. T. · ca 1896

In about 1886 the Swede W. T. Odhner, who worked in St. Petersburg, Russia, opened his own shop where he worked on improvements to the pinwheel calculating machine he had introduced the previous decade. By 1890, Odhner had a commercial product, and had begun to produce calculating machines in some numbers. In 1893 he exhibited his arithmometer, or reckoning machine, at the Columbian Exposition, a World’s Fair held in Chicago.