The first Mechanical Calculator invented in 1623

The first mechanical calculator was invented in 1623 by Wilhelm Schickard, a professor at the University of Württemberg in Tübingen.

The calculator consisted of three components: an adder which was the core part of the machine, a multiplier unit based on Napier's bones mounted on rotatable cylinders and a simple buffer memory for one decimal number. The mechanical calculator could be used for all four basic arithmetic operations.

Wilhelm Schickard and his family were all killed by the plague in 1635 during the Thirty Years War and his invention fell into oblivion.

Documents and construction sketches of the calculator were rediscovered in the 1930s and a fully functional replica was build during the years 1957 to 1960. There are several replicas today in different museums, but all of them are not allowed to be used by the museum visitors. Therefore I decided to build a replica by myself. I finished it around a year and a half ago and it is fully functional as well. It works quite good.

For more information about the calculator click here:
The first mechanical calculator - Schickard 1623