Editing Mechanical calculator (section)

===Overview===
{{further|Pinwheel calculator|Leibniz wheel}}
The 18th century saw the first mechanical calculator that could perform a multiplication automatically; designed and built by [[Giovanni Poleni]] in 1709 and made of wood, it was the first successful calculating clock. For all the machines built in this century, division still required the operator to decide when to stop a repeated subtraction at each index, and therefore these machines were only providing a help in dividing, like an [[abacus]]. Both pinwheel calculators and Leibniz wheel calculators were built with a few unsuccessful attempts at their commercialization.