born at brest in 1652, he was trained by the jesuits and became professor of mathematics at the royal seminary at toulon where he died in 1700, aged 48. he spent twelve years at sea with victor marie, duc d'estrées, montemart, duc de vienne and anne hilarion de tourville during which time he analysed the practical limitations of ship handling and sought to create a system of sailing. brian tunstall considers him the greatest of all the french tactical theorists.