Blaise Pascal

Pascaline Calculator
Computing and Telecommunications

Mathematician and inventor Blaise Pascal was born in Clermont-Ferrand, France on June 19, 1623. His mother passed away when he and his two sisters were very young, and their father Étienne became solely responsible for their upbringing. Étienne Pascal was a judge of the tax court in Clermont-Ferrand, who moved the family to Paris in part to further the education of his son, who was showing early potential for academic brilliance. 

Pascal became interested in geometry at age 12, and taught himself quickly about the properties of figures. His father, personally taught his son at home with the help of tutors, had been reluctant to allow him to study mathematics before age 15, but he recognized his son’s exceptional ability in the subject and gave him a copy of the book Euclid’s Elements. By age 14, Pascal was meeting weekly with prominent French mathematicians – the group that would form the foundation for the French Academy – and by age 16 he was developing theories, beginning with his essay on conic sections. This work was published in 1640. 

In December of 1639, Pascal’s father had moved the family to Rouen where he took a job as tax collector for the region. Pascal’s invention of the mechanical calculator in the early 1640s was born out of a desire to help his father in collecting taxes. He was the second person known to have created a device of this kind. A company by the name of Schickard had manufactured a type of mechanical calculator in 1624. Until 1645, Pascal worked on improvements to the machine, which was called the Pascaline. It resembled the mechanical calculators of the 1940s. 

The French money system presented Pascal with many technological challenges, as there were, at the time, 20 sols in a livre and 12 deniers in a sol. This made his task much more difficult than it would have been if the system was based on factors of 100. Nevertheless, he was able to construct a machine that was reasonably accurate. The Pascaline could only add and subtract; multiplication and division were done using a series of additions and subtractions. The machine had eight movable dials that added up to eight figured long sums. Production of the machines started in 1642. Few machines were sold however, and manufacture ceased ten years later. Pascal worked on many versions of the devices, leading to his attempt to create a perpetual motion machine. He has been credited with introducing the roulette machine, which was a by-product of these experiments. 

Meanwhile, Pascal continued to experiment in analytical geometry as well as physics. His father died in 1651, and in 1653 Pascal took over the family’s estate. At that time, he began to concentrate fully on developing his theories, creating the arithmetical triangle, and together with Fermat, creating the calculus of probabilities. He also began a series of experiments on atmospheric pressure. He published the “Treatise on the Equilibrium of Liquids” in 1653. 

In 1654, Pascal was spared in a near-deadly horse and carriage accident and became extremely religious. He was inspired to write on philosophical topics. Some of these writings have become very well-known, especially his “Provinciales” and “Pensées.” He turned away from scientific work for several years, until in 1658 he completed a full account of the geometry of the cycloid. He died of cancer in 1662 at the age of 39, in Port Royal.