Henry Slade

Henry Slade (1835–1905) was a famous fraudulent medium who lived and practiced in both Europe and North America.

Slade was most well known as a slate-writing medium. During his séances he would place a small slate with a piece of chalk under a table and would claim spirits would use it to write messages. According to Joe Nickell, Slade was repeatedly caught faking the spirit messages in his séances and he produced his phenomena by a variety of magic tricks.

Science writer Karen Stollznow has noted that:

"Slate writing was a simple parlor trick, often involving a double-sided chalkboard or a hidden slate upon which the "message" was already written. Many mediums were caught faking the practice, including Henry Slade, the man who discovered the phenomenon. Slade was writing these messages from the "dead" using tiny pieces of chalk held in the fingers of either hand, the toes of either foot, or his mouth."

In 1872, Slade was caught in fraud in New York by John W. Truesdell, who had two sittings with him. During the séance Truesdell observed Slade using his foot to move objects under the table, and writing on a slate. In a séance Stanley LeFevre Krebs employed a secret mirror and caught Slade swapping slates and hiding them in the back of his chair.

In a séance in 1876 in London Ray Lankester and Bryan Donkin caught Slade in fraud. Lankester snatched the slate before the "spirit" message was supposed to be written, and found the writing already there. He was prosecuted for fraud on October 1, 1876 in London and was sentenced to three months in prison. However, Slade made an appeal, which was sustained, on the ground that the words "by palmistry or otherwise" had been omitted in the indictment. Before he could be arrested on the new summons, he fled to America.

Slade also performed a trick where he would play an accordion with one hand under the table. The magician Chung Ling Soo exposed how Slade had performed the trick.

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