Bernouilli, Daniel, second son of John Bernouilli (q.v.), was born February 9th, 1700, at Groningen. After studying medicine he turned to mathematics, of which he was appointed professor at St. Petersburg in 1725. In 1733 he withdrew to Basel, where he was professor first of anatomy and botany and afterwards of experimental and speculative philosophy. He published several mathematical treatises, the chief being his Hydrodynamica, (1738), the first work on that subject. In his later years he directed his attention to the study of probabilities with special reference to social and economic matters. He was a member of the Academies of Berlin, Paris, and St. Petersburg, and F.R.S. of London. He died in 1782.