IVORY, SIR JAMES (1765-1842), Scottish mathematician, was born in Dundee in 1765. In 1779 he entered the University of St. Andrews, distinguishing himself especially in mathematics. From 1804-16, he occupied a chair of mathematics at the Royal Military College, Marlow (now Sandhurst). He contributed many memoirs to the Philosophical Transactions, the most im portant being one in 1809 giving a theorem on the attraction due to a homogeneous ellipsoid, which is now known as Ivory's Theorem. Ivory received the Copley medal in 1814, was elected
F.R.S. in 1815, and was connected with several other scientific societies. He died in London on Sept. 21, 1842.