In the grandly layered Large Library at Goodwood House in West Sussex, Charles Gordon-Lennox is casting his mind back to his earliest memory of his family art collection. “Probably my grandfather telling me that the Canalettos were very valuable – very important, very valuable,” says the dapper Duke of Richmond and Gordon with a grin. Clad in a caramel-coloured suit and wearing a pair of round-framed tortoiseshell glasses, the 70-year-old is in characteristically energetic mood….

