Sir Arthur Conan Doyle went to a meeting of the Society of American Magicians at the Hotel McAlpin in New York City On June 3, 1922 to present a wonder to the gathered illusionists — including his friend and society chairman, Harry Houdini. He prefaced his display by saying he was going to show the waiting magicians extinct creatures that were "psychic" and "preternatural".
When the movie screen flickered to life, the assembled magicians were astonished by a film of life-like dinosaurs. The scene showed a group of grazing herbivore dinosaurs harried by vicious Tyrannosaurus rexes. Then an intense battle broke out between the aggressive beasts, leading to the broken back and death of the loser — but the victor's triumphant meal was interrupted by a charging Triceratops. The magicians wondered if this could possibly be real. But the dinosaurs' bodies moved so realistically, and the way the muscles rippled under the skin seemed very convincing.
Was this a hoax or some film taken in the fourth dimensions, where fairies and spirits lived? Doyle's word that the creatures were "psychic" and "preternatural" was enough to make it appear reliable. After all Sir Arthur Conan Doyle, the author of Sherlock Holmes, had become a very ardent practitioner of spiritualism and occult research. And he'd never mixed practical joking in with his serious writings on psychic phenomenon. This was a man that had written two newspaper articles for The Strand to publicize the Cottingley Fairy photos and to convince the public of the existence of fairies. He was a true believer, who wasn't known for making light of fantastical subjects and was in America on a spiritualism lecture circuit.
The magicians' confusion was cleared up the next day with the delivery of a letter from Doyle to the renowned magician Harry Houdini:
My Dear Houdini:
My cinema interlude upon the occasion of the magician's dinner should, I think, be explained, now that its purpose was fulfilled. The purpose was, simply, to provide a little mystification to those who have so often and so successfully mystified others.
In presenting my moving dinosaurs I had to walk warily in my speech, so as to preserve the glamour and yet say nothing which I could not justify as literally true. But I was emphatic that it was not occult and only psychic in so far as all things human come from a man's spirit.
It was preternatural in the sense that it was not nature as we know it. All my other utterances were, as I think you will agree, within the actual facts.
The dinosaurs and other monsters have been constructed by pure cinema, but of the highest kind, and are being used for ‘The Lost World' picture which represents pre-historic life upon a South American plateau. Having such material at hand and being allowed by the courtesy of Watterson Rothaker to use it, I could not resist the temptation to surprise your associates and guests. I am sure they will forgive me if for a few short hours I had them guessing.
And now, Mr. Chairman, confidence begets confidence and I want to know how you got out of that trunk.
Arthur Conan Doyle
Yes, Sir Arthur Conan Doyle punked Harry Houdini.
At the time it was probably good-natured, since the two were good friends — but they had a strange relationship. Houdini worked hard to discredit fraudulent mediums. And the spiritualist leaders decided Houdini was doing this to hide his own spiritual powers, and weirdly Doyle fell into this camp. He spoke frequently of his friend's true powers, while Houdini actively denied them.
Shortly after the dinosaur movie showing, Doyle vacationed in Atlantic City and invited Houdini to visit. Doyle's wife Lady Jean invited Houdini to a private séance in order to contact his beloved dead mother. Though skeptical, Houdini fully participated, because he wanted to give his friends the benefit of the doubt. It was a complete disaster. Lady Jean was supposed to be channeling Houdini's mother, via automatic writing — but the transcript was error ridden and factually incorrect. Houdini's mother could barely speak English, let alone write pages worth. And even more damning were the crosses drawn on the pages. His mother was Jewish. All the inconsistencies and the failed tests during the séance showed how fake it was.
Houdini and Doyle's friendship was ruined by that encounter. Even though it was not maliciously intended, what boils down to a prank about a man's dead mother never goes over well.
HIS DINOSAUR FILM A HOAX, SAYS DOYLE: Moving Picture of Prehistoric ...New York Times (1857-1922); Jun 4, 1922;
ProQuest Historical Newspapers: The New York Times (1851-2008) pg. 18