Second son of preceding; entered the army at 19, and fought with his regiment, the Cameronians, at Steinkirk; studied law for some time at Leyden, but went back to the army, and by 1701 was a lieutenant-colonel in the Scots Foot Guards, and in 1706 colonel of the Cameronians; fought with distinction under Marlborough at Venlo, Ramillies, Oudenarde, and, as commander of a brigade, at the siege of Lille and at Malplaquet; was active in support of the Hanoverian succession, and subsequently in the reigns of George I. and II. filled important diplomatic and military posts (1673-1747).