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Animation produced in collaboration with the **Musée des Arts et Metiers **- Paris.

The arithmetic machine created by Blaise Pascale (1623-1662) - the Pascaline - was one of the first mechanical calculating devices (first model 1642). It's a calculating machine because the carrying over across places occurs automatically.

It enables one to directly add and subtract. It is also possible to multiply and divide using successive additions and subtractions.

**Click **on the sliding bar at top to change operations (addition or subtraction).

**Click** on a digit on the toothed wheels or just point at it with the stylus.

**Click **on the "return" button then add 1 to return the Pacaline to zero.

- To illustrate the nine's complement method. To link this method with that of the complements of 2 used in natural binary encoding (computers).

It was at the age of 19 that Blaise Pascale (scientist and philosopher) produced the first model of the Pascaline, to aid his father, who was a tax collector in Rouen.

Unlike an **abacus**, the…