He lived in Edinburgh and associated with several major figures of Scottish learned society, including philosopher and historian David Hume, political philosopher and economist Adam Smith, and architect Robert Adam.was a brother of Commodore George Johnstone and first cousin of Patrick Ferguson.
He lived in Edinburgh and associated with several major figures of Scottish learned society, including philosopher and historian David Hume, political philosopher and economist Adam Smith, and architect Robert Adam. He was a brother of Commodore George Johnstone and first cousin of Patrick Ferguson.