Photographic portraits taken by Dr. Hugh Welch Diamond of patients from Surrey County Asylum in England where he worked as a psychiatrist. Diamond was one of the very early practitioners of photography and certainly the first to systematically use it in the attempted treatment of mental illness. An advocate of the pseudo-science of physiognomy, in which the face was believed to be the mirror of the soul, Diamond proposed that through studying the faces of patients, physicians could identify and diagnose mental complaints. The faces of the patients were seen to represent 'types' of mental illness such as melancholia and delusional paranoia. As explained in an 1856 paper titled 'On the Application of Photography to the Physiognomy and Mental Phenomena of Insanity': "the Photographer catches in a moment the permanent cloud, or the passing storm or sunshine of the soul and thus enables the Metaphysician to witness and trace out the visible and the invisible in one important branch of his researches into the Philosophy of the human mind".