Leonora Piper (nee Leonora Evelina Simonds; 27 June 1857 - 3 June 1950) was a famous American trance medium in the area of Spiritualism. Piper was the subject of intense interest and investigation by American and British psychic research associations during the early 20th century, most notably William James and the Society for Psychical Research. Researchers and scientists who studied Piper’s mediumship have described mentalist techniques such as cold reading, muscle reading and fishing , all techniques that she may have used to gather information about seance sitters, so she could appear to have unexplained insight. Science writer and mathematician Martin Gardner dismissed Piper as a clever charlatan.