Claude François Milliet Dechales

Claude François Milliet Dechales, who lived from 1621 to 1678, was a French Jesuit priest and mathematician, born in Chambéry in Savoy as the son of the first president of the Sovereign Senate of Savoy. He entered the Jesuits at fifteen, took part in the French Jesuit mission to the Ottoman Empire and taught literature in the schools of his order for nine years. Louis XIV had him appointed professor of hydrography in Marseille, where he taught navigation and military engineering, and he later taught at Trinity College in Lyon and at a college in Turin, where he died. He is best remembered for the Cursus seu Mundus Mathematicus, published in Lyon in 1674, a complete course of mathematics, and for his editions of Euclid, whose Elements he made easier to follow and which appeared in English in 1685. He also wrote on fortification, navigation and local motion.