 In 1875, he left St. Thomas's Hospital, where he was dean of the medical school, to become obstetric physician at St. George's Hospital; there he was elected consulting obstetric physician in 1885.He had also acted as physician to the Seamen's Hospital, the East London Hospital for Children, and the Royal Maternity Hospital.Barnes took a prominent part in founding the Obstetrical Society of London in 1858 and was president in 1865–6.