In the later half of the 20th century, Western mediumship developed in two different ways. One type involved clairaudience or sensitives who hear spirit, and then relay what they hear to their clients. The other incarnation of non-physical mediumship is a form of channeling in which the channeler goes into a trance, or "leaves their body", allowing a spirit entity to borrow their body, who then speaks through them. When in a trance the medium appears to come under the control of the spirit of a departed soul, sometimes entering into a cataleptic state, although modern channelers may not. Some channelers open the eyes when channeling, and remain able to walk and behave normally. The rhythm and the intonation of the voice may also change completely.
The psychical researchers Eric Dingwall and Harry Price re-published an anonymous work written by a former medium entitled Revelations of a Spirit Medium (1922) which exposed the tricks of mediumship and the fraudulent methods of producing "spirit hands". Originally all the copies of the book were bought up by spiritualists and deliberately destroyed. In 1923, the magician Carlos María de Heredia revealed how fake spirit hands could be made by using a rubber glove, paraffin and a jar of cold water.
In 1954, the psychical researcher Rudolf Lambert published a report revealing details about a case of fraud that was covered up by many early members of the Institute Metapsychique International (IMI). Lambert who had studied Gustav Geley's files on the medium Eva Carrière discovered photographs depicting fraudulent ectoplasm taken by her companion Juliette Bisson. Various "materializations" were artificially attached to Eva's hair by wires. The discovery was never published by Geley. Eugéne Osty (the director of the institute) and members Jean Meyer, Albert von Schrenck-Notzing and Charles Richet all knew about the fraudulent photographs but were firm believers in mediumship phenomena so demanded the scandal be kept secret.
In 1992, Richard Wiseman analyzed the Feilding report of Eusapia Palladino and argued that she employed a secret accomplice that could enter the room by a fake door panel positioned near the séance cabinet. Wiseman discovered this trick was already mentioned in a book from 1851, he also visited a carpenter and skilled magician who constructed a door within an hour with a false panel. The accomplice was suspected to be her second husband, who insisted on bringing Palladino to the hotel where the séances took place. Massimo Polidoro and Gian Marco Rinaldi also analyzed the Feilding report but came to the conclusion no secret accomplice was needed as Palladino during the 1908 Naples séances could have produced the phenomena by using her foot.
In March 1902 in Berlin, police officers interrupted a séance of the German apport medium Frau Anna Rothe. Her hands were grabbed and she was wrestled to the ground. A female police assistant physically examined Rothe and discovered 157 flowers as well as oranges and lemons hidden in her petticoat. She was arrested and charged with fraud. Another apport medium Hilda Lewis known as the "flower medium" confessed to fraud.
^ Joseph McCabe. (1920). Spiritualism: A Popular History from 1847. Dodd, Mead and Company. pp. 110–12. A Mr. Merrifield was present at one of the sittings. Home's usual phenomena were messages, the moving of objects (presumably at a distance), and the playing of an accordion which he held with one hand under the shadow of the table. But from an early date in America he had been accustomed occasionally to "materialise" hands (as it was afterwards called). The sitters would, in the darkness, faintly see a ghostly hand and arm, or they might feel the touch of an icy limb. Mr. Merrifield and the other sitters saw a "spirit-hand" stretch across the faintly lit space of the window. But Mr. Merrifield says that Home sat, or crouched, low in a low chair, and that the "spirit-hand" was a false limb on the end of Home's arm. At other times, he says, he saw that Home was using his foot."
Colin Fry was exposed in 1992 when during a séance the lights were unexpectedly turned on and he was seen holding a spirit trumpet in the air, which the audience had been led to believe was being levitated by spiritual energy. In 1997, Massimo Polidoro and Luigi Garlaschelli produced wax-moulds directly from one's hand which were exactly the same copies as Gustav Geley obtained from Franek Kluski, which are kept at the Institute Metapsychique International.
In 1880 the American stage mentalist Washington Irving Bishop published a book revealing how mediums would use secret codes as the trick for their clairvoyant readings. The Seybert Commission was a group of faculty at the University of Pennsylvania who in 1884–1887 exposed fraudulent mediums such as Pierre L. O. A. Keeler and Henry Slade. The Fox sisters confessed to fraud in 1888. Margaret Fox revealed that she and her sister had produced the "spirit" rappings by cracking their toe joints.