Blaise Pascal, French mathematician and philosopher, is mostly know as the name behind a “Pascal’s Law”. While researching pressure of liquids, he explained principle that described how a liquid in a vessel carried pressure equally in all directions. Pascal’s Law is one of the cornerstones of hydraulics. But not everyone knows that Blaise Pascal had also invented a mechanical adding machine, dabbed “Pascaline”. Pascal’s father was a Superintendent of Taxes and having mathematician for a son had certain benefits: Pascal’s interest in calculating resulted in creation of a calculator “Pascaline” in 1642. Pascal’s took our civilization one step closer to the invention of computers. Pascal’s machine was also known as “Arithmatique” and “Numerical Wheel Calculator”. The mechanical calculator industry would not be the same without the Pascaline.

The main principle behind Pascaline mechanism is ability calculate with 8 figures and carrying of 10’s , 100’s, and 1000’s and so on. Pascal’s device used a series of toothed wheels with the digit 0 through 9 displayed around the circumference of each wheel. The wheels were turned manually by hand and handled numbers up to 999,999.999. Each dial was associated with a one-digit display window located directly above it. To input a digit, the user placed a special stylus in the corresponding space between the spokes, and turned the dial until a metal stop at the bottom was reached. In a way it was similar to the a rotary telephone dial (makes you wonder if Pascaline was an inspiration for the rotary phone interface, as well, doesn’t it?) The number would display in the opening at the top of the calculator. To add a number, user would re-dial the second number; a horizontal bar hides the complement numbers but the value of the sum of both numbers would be displayed in the accumulator.

Pascal’s device was one of the world’s **first mechanical adding machines**. Since 1642, Pascal went through 50 prototypes before presenting his first machine to the public in 1645. He then built twenty more machines during the following years, trying to improve the original design of Pascaline. It was continuously improved during the following centuries. The development of mechanical calculators in Europe and then all over the world then followed Pascal’s efforts. Gottfried Leibniz, Thomas de Colmar, Dorr E.Felt, and David Roth were the most famous contributors to the process.

In 1971, three centuries later, the invention of the microprocessor developed for a Busicom calculator opened the new era of calculating machines: we cannot imagine a computer without the microprocessor embedded into the system.