The fraudulent medium Ronald Edwin confessed he had duped his séance sitters and revealed the fraudulent methods he had used in his book Clock Without Hands (1955). The psychical researcher Tony Cornell investigated the mediumship of Alec Harris in 1955. During the séance "spirit" materializations emerged from a cabinet and walked around the room. Cornell wrote that a stomach rumble, nicotine smelling breath and a pulse gave it away that all the spirit figures were in fact Harris and that he had dressed up as each one behind the cabinet.
^ "Glossary of Key Words Frequently Used in Parapsychology" Archived 2010-12-24 at the Wayback Machine, Parapsychological Association website. "Materialization: A phenomenon of physical mediumship in which living entities or inanimate objects are caused to take form, sometimes from ectoplasm." Retrieved January 24, 2006 "Medium – Definition". Dictionary.com. Retrieved 23 March 2007.