James Clerk Maxwell was born in Edinburgh, on the 13th of June, 1831. His father, who was brother to Sir George Clerk, of Pennicuick, was at first known as John Clerk, but adopted the name of Maxwell on succeeding to an estate called Nether Corsock, which had come into the Clerk family through the marriage of a Miss Maxwell. To this estate he added, by purchase, that of Glenlair, the name of which became afterwards closely associated with that of his son.