Pascal (historical replica)
In 1642 at the age of only 19, the French religious philosopher, physicist and mathematician Blaise Pascal (1623-1662) invented an adding machine for 8-place additions and subtractions to ease the work load of his father who was a tax officer in Normandy. A stylus was used to enter the digits of a number, which were then transferred to the main mechanism. A novel feature was the automatic “gravity feed” tens-carry mechanism, for which the machine had to be in a level position. Up to the year 1652 Pascal built about fifty different models, of which nine have survived (Conservatoire National des Arts et Métiers, Paris (4), Musée du Ranquet, Clermont-Ferrand (2), Mathematisch-Physikalischer Salon, Dresden (1), Collection Léon Parcé (1), IBM, New York (1)). The 8-place machine shown here is a replica that was built in the early 19th century. Six of the eight setting wheels turn dials with the numbers 0 to 9 (from “Centaine de Mille“ down to “Unité“) and the remaining two show 20 and 12 places respectively (for “Sols“ and “Deniers”). This arrangement, plus the absence of the coat-of-arms found on the front part of later machines, indicates that this machine is probably similar to the one Pascal gave to chancellor Séguier (today in the Conservatoire National des Arts et Métiers, Paris). However, it differs from the Séguier machine in one important aspect: its units are printed on eight square ivory plates (as in the illustration of Diderot and d’Alembert 1751), a feature that is found on none of the nine surviving machines. Apart from this, the exterior of the machine closely resembles the IBM-machine (handles, brass plates, wooden edges, other attachments). The cover of the machine bears a copy of the handwritten label that Pascal later placed on his first machine of 1642 (today also in Paris), stating: “Esto Probati instrumenti symbolum / hoc / Blasius Pascal arvernus Inventor / 20 May 1652.“ (“May this signature of Blaise Pascal, Gallic inventor, serve to guarantee that this is a tested and approved instrument - 20. May 1652“.) Thus it is probable that this 19th century French replica either incorporates features of several versions or resembles a no longer existing version, as depicted by Diderot and d’Alembert.