Computing archaeology: design and implementation of a Leibniz type calculator with Scratch

Leibniz type mechanical calculator with Scratch

Salvador Pérez Heras


This new section of the museum includes a simulation of the mechanical calculator Schubert to learn its functioning and its parts. There is also a video of a calculator in the Museum of Computing.

This calculator has been introduced through programming language Scratch where you can make all kind of applications in open code, accessible to anyone and even modify those applications. Previously, some study tasks to know better this calculator and others have been carried out.


The mechanical calculator Schubert was made in the 50s in the 20 century. Its name comes from its inventor Emil Schubert (1883-1952). After failing with his first company, in 1938 founded a new one with his own name. While the World War 2 was still on, the company began to make this calculator until the 60s.

This machine contains the famous stepped reckoner inherited by the philosopher and mathematician Gottfried Wilhelm Leibniz. This device has been used by most of the mechanical calculators until the electric calculators now that, a part of making additions and subtractions, it could also make multiplications, division and calculate the square root.


  1. Press the green flag to start the app.
  2. Press the screen to read the instructions.

To access the simulator page in the Sractch website go to –> Schubert

Video of the functioning of the calculator

We are going to show you the use of a mechanical calculator handed over by the Museum of Informatics. It is a Minerva calculator, made in Spain.

Creator of the calculator: Salvador Pérez Heras

Tutor: Xavier Molero Prieto