In the late 19th and early 20th centuries, spiritualism—a belief that the spirits of the dead can communicate with the living—was all the rage. There was no trendier activity than holding a séance led by a medium, who would mediate between the living and the dead. The medium not only delivered messages from the dearly departed, but also demonstrated the presence of spirits in the room by levitating objects, ringing bells, and producing a substance from her body known as ectoplasm.
Those were excellent tricks, but that’s all they were—mediums were often shown to be frauds. “Exposures are of frequent occurrence, many of them highly sensational in character,” wrote the New York Times in a November 21, 1909 article titled “Notable Charlatans Exposed In The Past: A Weird History That Leaves Spiritualism Undaunted.” (You can view a PDF of the article here.) “Slate writing, spirit pictures, table tipping, rapping, and other features of Spiritualism have been exposed time and again. The exposures mount into the hundreds.”
In 1924, Houdini was part of a committee investigating Boston medium Mina “Margery” Crandon, the wife of a respected surgeon and Harvard faculty member. Crandon had entered herself in a contest of sorts, run by Scientific American, that offered a monetary prize to the medium able to produce a “visual psychic manifestation.” Here, Houdini is shown in the “Margie Box,” which was intended to limit the medium’s physical movements within the séance room and contain her suspected manipulations; Houdini built the box himself. The committee sat in on 20 séances, and the debate about Crandon’s abilities lasted for a year, but ultimately, Scientific American opted not to award her the money.