Dr. Hugh Welch Diamond was one of the most important figures in early British photography. He made his first photographs in April 1839, just three months after the announcement of photography’s invention. In the 1840s he befriended one of his patients, Frederick Scott Archer and subsequently became one of the first people to use Archer’s collodion process. In May 1856 Diamond presented a paper to the Society called 'On the Application of Photography to the Physiognomy and Mental Phenomena of Insanity' when he was a physician at the Surrey County Asylum and Secretary to the Photographic Society of London. Diamond stated that photography was invaluable in the treatment of mental illness. He proposed that by studying the faces of patients, physicians could identify and diagnose mental complaints. These beliefs were rooted in the pseudoscience of physiognomy, where the face was seen as the mirror of the soul. For Diamond, the faces of the patients represented 'types' of mental illness such as melancholia and delusional paranoia. (via National Media Museum)