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slate writing

Slate writing was a trick used by mediums that involved school Henry Sladeslates and the claim that spirits were writing messages on them. Usually, a pair of slates would be used. They would be shown to the viewer clean, hidden in some way, and then shown to the viewer again but now with a written message. Henry Slade (1840-1905) is credited with inventing slate writing and incorporating it in his act as a psychic medium. Slade called himself a spiritual doctor and is often referred to as Dr. Henry Slade. Whether he invented slate writing or not, I can't say, but he popularized the trick and was found guilty of fraud several times for his efforts.

The trick was done in several ways, but could be done either by surreptitious replacement of a blank slate with a slate that had a prewritten message on it or by surreptitious writing on the blank slate by the medium with a hidden piece of chalk. I imagine the trick could be done with or without the help of an accomplice. Clearly, it's a good trick when done properly.

At one time Slade was reputed to be worth $1 million. When he was at the height of his fame it was impossible to gain an audience with him without making arrangements weeks in advance. He lived with great prodigality, but as he grew older, his wonderful powers weakened and gave way under the strain of his dissipation. His fortune was soon squandered and he eked out a miserable existence by slate writings at 50 cents a sitting.*

His luck ran out, though, and Slade died a poor man in a sanitarium in Battle Creek, Michigan.

The idea of a spirit writing silly messages on a slate kept out of view may strike us as absurd as the idea of pulling cheesecloth out of a sleeve and calling it ectoplasm from the spirit world, but at one time such ideas were taken seriously by many looking for some evidence of the reality of life after death. Perhaps the fact that science was discovering more and more about the universe that supported materialism was disconcerting and opened up a crack in the critical thinking abilities of laymen and scientists alike. Whatever the reason, ideas that seem transparently deceptive to us (séances in dark rooms, table rapping, apports and deports, spirit photography, etc.) were once willingly accepted as proof of the spirit world by educated people, many of them eminent scientists.

Physicist Johann Zollner, an expert on illusions, was taken in by Slade and wrote a book (Transcendental Physics) in which he declared that Slade's tricks with slates were not tricks at all but the real thing:

Friday, 14th December 1877 (11.0 to 11.40 A.M.). Today, first one of the slates kept always in readiness, which I myself selected and cleaned, was laid open with a bit of slate-pencil upon the floor under the table. Now, while Slade had both his hands linked with ours upon the table, and his legs, turned sideways, were continually visible, writing, loudly perceptible by us all, began on the slates lying below. When we raised it, there were on it the words—‘Truth will overcome all error!’*

Sir William Fletcher Barrett, a professor of physics at the Royal College of Science in Dublin, and one of the founders of the still-existing Society for Psychical Research (SPR), wrote of Slade:

I was very much impressed with the successful results that I had with Slade in broad daylight and under conditions that seemed to render fraud impossible (and until I am shown how the writing could be accomplished by legerdemain I find it stupendously difficult to accept that hypothesis)...’*

Alfred Russel Wallace, co-discoverer of natural selection, believed that slate writing demonstrated the existence of spirits. He knew this, he said, despite knowing that Slade's fraud had been exposed at trial by a conjurer. He knew this because he saw it with his own eyes!

In 1876, the famous British conjuror J. N. Maskelyne was a prominent witness against Henry Slade when Slade was charged in the U.K. with fraud. The court case caused great excitement, and though the renowned physicist Lord Rayleigh (1842-1919) had publicly declared Slade to be genuine, Maskelyne was easily able to demonstrate to the satisfaction of the court that Slade's slate writing was brought about by trickery. (James Randi)

Wallace wrote the following letter to the editor of the Spectator dated 6 October 1877:

Sir,--I trust you may consider the following experiment worthy of record in your paper, because it differs from cases of abnormal slate-writing of which evidence was adduced at the trial of Slade, and because it affords a demonstration of the reality of the phenomenon and the absence of imposture from which there seems no escape. I confine myself to this one experiment, and narrate the essential facts only.

The sitting was at a private house in Richmond, on the 21st of last month. Two ladies and three gentlemen were present, besides myself and the medium, Dr. Monck. A shaded candle was in the room, giving light sufficient to see every object on the table round which we sat. Four small and common slates were on the table. Of these I chose two, and after carefully cleaning and placing a small fragment of pencil between them, I tied them together with a strong cord, passed around them both lengthways and crosswise, so as effectually to prevent the slates from moving on each other. I then laid them flat on the table, without losing sight of them for an instant. Dr. Monck placed the fingers of both hands on them, while I and a lady sitting opposite me placed our hands on the corners of the slates. From this position our hands were never moved, till I untied them to ascertain the result. After waiting a minute or two, Dr. Monck asked me to name any short word I wished to be written on the slate. I named the word "God." He then asked me to say how I wished it written. I replied, "lengthways of the slate;" then if I wished it written with a large or a small "g," and I chose a capital "G." In a very short time, writing was heard on the slate. The medium's hands were convulsively withdrawn, and I then myself untied the cord (which was a strong silk watch-guard, lent by one of the visitors), and on opening the slates, found on the lower one the word I had asked for, written in the manner I had requested, the writing being somewhat faint and laboured, but perfectly legible. The slate with the writing on it is now in my possession.

The essential features of this experiment are,--that I myself cleaned and tied up the slates, that I kept my hand on them all the time, that they never went out of my sight for a moment, and that I named the word to be written and the manner of writing it after they were thus secured and held by me. I ask, how are these facts to be explained, and what interpretation is to be placed upon them?--I am, Sir, &c., Alfred R. Wallace.

I was present on this occasion, and certify that Mr. Wallace's account of what happened is correct.--Edward T. Bennett.

In 1886-87, psychical researchers Richard Hodgson (1855-1905) and S. J. Davey "exposed mediumistic slate-writing as bogus, virtually ending it as a spiritualist technique." Wallace was the last gasp, you might say, of those on the sinking ship of slate writing by spirits.

In 1887, Hodgson became secretary of the newly-founded American Society for Psychical Research. He remained skeptical of most mediums and their tricks until he was taken in by Mrs. Leonore Piper. His conversion might shed some light on why many educated people, including many trained scientists, would be so easily deceived.

Hodgson was sceptical of her earlier communications but at last in 1896-97 he found solace by accepting her 'control's' utterances as empirical evidence of the survival of personalities after death and of their power to communicate with the living. He was now convinced of the goodness and unity of the cosmos. He had 'not a mere consciousness of something there; [but] fused in the central happiness of it … a startling awareness of some ineffable Love and Wisdom' amounting to 'the one perception of Reality'. Mrs Piper's 'controls' gave him news of his mother and Jessie D--and of Madame Blavatsky, whose 'spirit was in the deepest part of Hell'.

The deception is easy because of the overwhelming desire to survive death and be reunited with loved ones, and to believe, despite the incontrovertible evidence to the contrary, that the universe is not indifferent to our existence. For some, even survival of consciousness and purposiveness to the universe would not satisfy their cosmic cravings. They want, like Hodgson, a universe of "ineffable Love and Wisdom." The contemplation of the fact of their existence as percipient beings against all odds and the magical discoveries of science about how things work and came to be cannot satisfy their unquenchable thirst for mysticism. Join that unquenchable thirst to a belief that one is too intelligent to be fooled by a trickster and you have a perfect formula for gullibility among the learned.

See also magical thinking, mentalist, spiritualism, and "A Short History of Psi Research" by Robert Todd Carroll.

further reading

books and articles

Christopher, Milbourne. ESP, Seers & Psychics (Thomas Y. Crowell Co. 1970).

Christopher, Milbourne. (1975). Mediums, Mystics & the Occult. Thomas Y. Crowell Co.

Gordon, Henry. Extrasensory Deception: Esp, Psychics, Shirley MacLaine, Ghosts, UFOs  (Buffalo, NY: Prometheus Books, 1987).

Stein, Gordon. "Spiritualism," in The Encyclopedia of the Paranormal edited by Gordon Stein (Buffalo, N.Y.: Prometheus Books, 1996).

Wiseman, Richard. Paranormality: Why We See What Isn't There, 2011.

Last updated 10-Sep-2011

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