Playfair, John; Borthwick, J.

John Playfair was born at Benvie, Dundee, on 10 March 1748, the son of a Minister. He was educated at home and then studied at St. Andrews University. At the age of eighteen, in 1766, he competed for the Chair of Mathematics at Aberdeen's Marischal College. He failed to secure it and went on to study theology at St. Mary's College and was licensed as a Minister in 1770, by which time he was in Edinburgh. In 1772 he was again unsuccessful in an attempt to win a Chair, this time the Chair of Natural Philosophy at St. Andrews. That year too, his father died and the responsibility for the family upon him. He became the Minister at Liff and Benvie, his father's church. He stayed at Liff and Benvie until 1783 when he became tutor to the Fergusons of Raith. In 1785, Playfair was appointed joint-Professor of Mathematics at Edinburgh University, with Dr. Adam Ferguson. In 1805 he exchanged this for the post of Professor of Natural Philosophy at Edinburgh. When peace at last came to Europe in 1815, after the Congress of Vienna, he travelled to France, Switzerland, and Italy, studying the geology and mineralogy of these countries. His publications include Elements of geometry (1795), Illustrations of the Huttonian theory of the Earth (1802), and Outlines of natural philosophy (1812). Professor John Playfair was the brother of William Playfair (1759-1823) the publicist. Playfair died in Edinburgh on 20 July 1819.