The fourth son of Benjamin Harrison (1734–1797), also treasurer of Guy's Hospital (himself second son of Sir Thomas Harrison (1700–1765), chamberlain of the city of London), he was born at
West Ham on 29 July 1771. He lived for twelve years with his father at Guy's, and succeeded him in the treasurership in 1797. For fifty years Harrison governed the hospital and managed its estates, despotically and without salary. With
Sir Astley Cooper he, in 1825, established Guy's as a complete medical school separate from
St. Thomas's Hospital, with which it had always previously been allied. Harrison resented an inquiry into the hospital administration which was made by charity commissioners in 1837, but no abuses were discovered. He was a Fellow of the
Society of Antiquaries of London, deputy governor of the
Hudson's Bay Company and
South Sea Company, and chairman of the
Exchequer Loan Board. He was selected as one of the three appeal commissioners for the city of London on the first imposition of an
income tax. Towards the end of his life, Harrison lived at
Clapham Common and was closely connected with the
Clapham sect. He died there on 18 May 1856, aged 84. ==Family==