JAMES DAVID (1809-1868).-Natural Philosopher, _s._ of Sir William F., of Pitsligo, was _b._ and _ed._ at Edin. He studied law, and was called to the Bar, but devoted himself to science, in which he gained a great reputation both as a discoverer and teacher. He was Prof. of Natural Philosophy at Edin., 1833-1859, when he succeeded Sir D. Brewst