I found out about the Pascaline purely by chance, when writing my latest novel, The Ladies’ Tale: Caroline and Philippa, due to be published this month (September 2020). I was looking for an interesting but expensive gadget for Harriet to own, and was really surprised to discover that the first calculator was invented as long ago as the 17thcentury!

Now any German computer historians reading this might immediately challenge me on my assertion that the Pascaline was the first calculator, because it seems that a German, Wilhelm Schickard, from Tübingen, in fact invented the first calculator around 1623. However, his machine didn’t survive, and only three documents about it have survived, one including a sketch of the machine, including its mechanism. It would seem that it was superior to Pascaline’s in that as well as addition it allowed the user to subtract, although it only operated in decimal, whereas Pascaline’s was more adaptable for the French and British currency system. The first copy of Shickard’s machine was made in 1960.

Having hopefully now excused myself to any German readers, the Pascaline was certainly manufactured and used by a number of people. A number of copies survive today. It was invented by Blaise Pascal, whose father Étienne Pascal was financial assistant in Normandy, and whose work involved him adding enormous amounts of numbers of coins. Anyone old enough to remember pre-decimal currency in Britain will shudder at the memory of having to add sums of pounds, shillings and pence, as there were 12 pennies in a shilling, and 20 shillings in a pound. (I’m old enough to remember this horror). The French currency followed a similar pattern, and soon Étienne’s son Blaise was drafted in to help with this formidable task, using manual calculations and abacus.
In 1642, at the age of nineteen, Blaise started to design a machine that would help with the calculations and a year later had completed his first version of it. Several copies were made, but he was not fully satisfied with it, as the mechanism was too fragile, so if the machine was jolted, or transported anywhere, it would often no longer work. While he was seeking to overcome this problem, a clockmaker in Rouen, having heard a verbal description of the machine, made a copy which didn’t work, but which, in view of its highly unusual appearance, was bought by a collector and put on display. Pascal was deeply upset by this and abandoned the whole project, fearing that more inferior or useless copies would be produced which would ruin the whole venture for him financially and destroy his reputation.

However, his friends submitted a copy of the machine to the French Chancellor, who was sufficiently impressed to encourage Pascal to continue with his work, and in 1645 Pascal gave a copy of the machine and a pamphlet he’d written about it to the chancellor. Later King Louis XIV granted Pascal a patent, prohibiting anyone to make copies of the calculator, which was described as: the main invention and movement is this, that every wheel and axis, moving to the 10 digits, will force the next to move 1 digit.

Pascal went on to design a number of prototypes, including decimal calculators, and ones which would calculate the French (and British) currencies. He did hope to make a profitable business from this invention, but the calculator was too expensive, costing between 100 and 500 livres. As 100 livres was enough to keep a modest man in comfort for a year, this was too expensive for all but the very rich to afford. He did manage to make it more reliable, although the decimal version of the machine has to be kept perfectly horizontal when in use, and the mechanism can jump if the box is jarred.
It seems that Pascal became obsessed with the machine, making some fifty different variations, and driving himself to a state of collapse. However by 1652 the machine was well known, not just in France but abroad, and the queens of Poland and Sweden had bought copies. Soon after this Pascal lost interest, and abandoned the project altogether, but continued work in mathematics until he had a profound religious experience in 1654. After that he gave up mathematical and scientific work and wrote a number of theological papers, including Provincial Letters, which are said to have influenced Rousseau and Voltaire, and the Pensées, which was not completed on his death in 1662, but which nevertheless was considered a masterpiece. He is regarded as one of the greatest masters of French prose. He is still remembered in France through the Blaise Pascal Chairs, which are given to outstanding international scientists, to allow them to conduct their research.