 On 8 November 1764, he was appointed physician to the Middlesex Hospital.He became licentiate of the College of Physicians in London on 30 September 1765 and made himself notorious by the magnificent entertainments he repeatedly gave at his house in Great George Street, Westminster.Pecuniary difficulties then forced him to leave England for Germany, where he first settled at Dresden and afterwards at Berlin, where he obtained the post of physician to Frederick the Great.