Schickard calculating clock
Reloj calculador de Schickard
- Date
- 1623 · confidence high
- Place
- Tübingen, Germany
- Credited to
- Wilhelm Schickard
- People
- 👤 Wilhelm Sch1592–1635
- Field
- Knowledge & symbols
⚠️ Disputed: the sources disagree.
What it is
The first known mechanical calculator, adding and subtracting with toothed wheels and automatic carrying of tens, and multiplying using Napier's cylinders. Described in letters to Kepler; the prototype was destroyed in a fire.
It became known only in 1935 and 1957, from letters to Kepler; whether the tens-carrying mechanism worked reliably is disputed. Its priority over Pascal is recognised today.
What it led to
- The concept of an arithmetical machine as an aid to astronomical calculation
- A conceptual precedent for the Pascaline (without direct influence)
Built on
- Pocket watchc. 1510
- Logarithms1614
- Clockwork gears