Generally they performed addition, subtraction, multiplication and division. Due to the great accuracy needed in the construction of such calculators, they were not very feasible until the 1800's. The calculator was constructed with levers for inputting data, results indicator and a revolution counter. This calculator was based on a cylinder with individual stepped teeth known as the Leibnitz wheel or step drum. This was a crucial step in mathematics.
Leibnitz constructed the first four function mechanical calculator in 1694.[Back to Timeline]