 Other psychical researchers who studied mediumship speculated that within the human body an unidentified fluid termed the "psychode", "psychic force" or "ecteneic force" existed and was capable of being released to influence matter.This view was held by Camille Flammarion and William Crookes, however a later psychical researcher Hereward Carrington pointed out that the fluid was hypothetical and has never been discovered.The psychical investigator W. J. Crawford (1881–1920) had claimed that a fluid substance was responsible for levitation of objects after witnessing the medium Kathleen Goligher.