Calculator - Original Odhner

This type of pin-wheel calculator was, invented by Willgodt T. Odhner in St. Peterburg, Russia, in 1874. (A calculator on similar principles was invented independently two years earlier by Frank Baldwin in the USA, but the Odhner was the successful design). Following the Russian Revolution of 1917 and the nationalization of the factory there, production moved to Sweden and the name "Original Odhner" was adopted.

This was the most successful type of general purpose mechanical calculator (ie. intrinsically capable of multiplication and division and not just "adding machines"). Up to the early 1970s dozens of manufacturers made machines based on and with a general resemblance to the Odhner. See www.vintagecalculators.com

The calculator shown upper right was donated by Ted Rippon. The calculator shown lower right was donated by Art Hall.