
Claude Dechales
The French Jesuit mathematician Claude Dechales (1621–1678) was best remembered for his book Cursus seu mundus mathematicus, a complete course of mathematics, published in Lyons in 1674. Dechales published also several other books, and in one of them—L’ art de naviger demontré par principes & confirmé par plusiers observations tirées de l’experience, published in Paris in 1677, he described a small counting device with a ratchet wheel as input and analog display indicators (see the image below).