I shall now sum up the subject of Dr. Slade’s spirit-slate writing, (Fig. 3) and endeavor to show how grossly exaggerated the reports of the medium’s performances have been, and the reasons for such misstatements. No one who is not a professional or amateur prestidigitateur can correctly report what he sees at a spiritualistic séance.
It is not so much the swiftness of the hand that counts in conjuring but the ability to force the attention of the spectators in different directions away from the crucial point of the trick. The really important part of the test, then, is hidden from the audience, who imagine they have seen all when they have not. Says Dr. Max Dessoir: “It must therefore be regarded as a piece of rare naiveté if a reporter asserts that in the description of his subjective conclusions he is giving the exact objective processes.”
This will be seen in Mr. Davey’s experiments. Mr. Davey, a member of the London Society for Psychical Research, and an amateur magician who possessed great dexterity in the slate-writing business, gave a series of exhibitions before a number of persons, but did not inform them that the results were due to prestidigitation. No entrance fee was charged for the séances, but the sitters, who were fully impressed with the genuineness of the affair, were requested to submit written reports of what they had seen. These letters, published in vol. iv of the Proceedings of the Society, are admirable examples of mal-observation, for no one detected Mr. Davey exchanging slates and doing the writing.
“The sources of error,” says Dr. Max Dessoir, in an article reproduced in the “Open Court,” “through which such strange reports arise, may be arranged in four groups. First, the observer interpolates a fact which did not happen, but which he is led to believe has happened; thus, he imagines he has examined the slate when as a fact he never has. Second, he confuses two similar ideas; he thinks he has carefully examined the slate, when in reality he has only done so hastily, or in ignorance of the point at issue. Third, the witness changes the order of events a little in consequence of a very natural deception of memory; he believes he tested the slate later than he actually did. Fourth and last, he passes over certain details which were purposely described to him as insignificant; he does not notice that the ‘medium’ asks him to close a window, and that the trick is thus rendered possible.”
Similar experiments in slate-writing were conducted by the Seybert Commission with Mr. Harry Kellar, the conjurer, after sittings were had with Dr. Slade, and the magician outdid the medium. The Seybert Commission found none of Slade’s tests genuine, and officially denied “the extraordinary stories of his performances with locked slates which constitute a large part of his fame.”
Dr. Slade began his Spiritualistic operations in London in the year 1876, and charged a fee of a guinea a head for séances lasting a few minutes. Crowds went to see him and he reaped a golden harvest from the credulous, until the grand fiasco came. Slade was caught in one of his juggling séances and exposed by Prof. Lancaster and Dr. Donkin. The result was a criminal prosecution and a sensational trial lasting three days at the Bow Street Police Court. Mr. Maskelyne, the conjurer, was summoned as an expert witness and performed a number of the medium’s tricks in the witness box. The court sentenced Slade to three months’ hard labor, but he took an appeal from the magistrate’s decision. The appeal was sustained on the ground of a technical flaw in the indictment, and the medium fled to the Continent before new summons could be served. He visited Paris, Leipsic, Berlin, St. Petersburg and other cities, giving séances before Royalty and before distinguished members of scientific societies; and afterwards went to Australia. He made money fast and spent it fast, but it took all of his ingenuity to elude the clutches of the police. In 1892, we find him the inmate of a workhouse in one of our Western towns, penniless, friendless and a lunatic.
Slade’s séances with Prof. Zoellner, of Berlin, in 1878, attracted wide attention, and did more to advertise his fame as a medium than anything else in his career.
Zoellner’s belief in the genuineness of Slade’s mediumistic marvels led him to write a curious work, entitled, “Transcendental Physics,” being an inquiry into the “fourth dimension of space.” Poor old Zoellner, he was half insane when these séances were held! We have the undisputed authority of the Seybert Commission for the correctness of this statement.
In Hamburg, Dr. Borchert wrote to Slade offering him one thousand marks if he would produce writing between locked slates, similar to the writing alleged to have been executed at the Zoellner séances, but the medium took no notice of the professor’s letter. The conjurer, Carl Wilmann, with two friends, had a sitting with Slade, but without satisfactory results for the medium. “Slade,” says Wilmann, “was unable to distract my attention from the crucial point of the trick, and threw down the slates on the table in disgust, remarking: ‘I can not obtain any results to-day, the power that controls me is exhausted. Come tomorrow!’” That tomorrow never arrived for Wilmann and his friends; Slade did not keep his appointment, nor could Wilmann succeed in obtaining another sitting with him. The medium had been warned by friends that Wilmann was an expert professor of legerdemain.
It was in 1886 that Slade created such a furore in Hamburg in Spiritualistic circles. A talented conjurer of that city, named Schradieck, after a few weeks’ practice succeeded in eclipsing Slade. He learned to write in reverse on slates, and produced writing in various colored chalks. Another one of his experiments was making the slate disappear from one side of the table where it was held a la Slade and appear at the opposite end of the table suddenly, as if held up to view by a spirit hand. Wilmann describes the effect as startling in the extreme and says Schradieck produced it by means of his left foot. After Slade’s departure from Hamburg, spirit mediums sprang up like toadstools in a single night. Wilmann in his crusade against these worthies had many interesting experiences. He gives in his work “Moderne Wunder” several exposes of mediumistic tricks, two of which, in the sealed slate line, are very ingenious. The medium takes a slate (one furnished by the sitter if preferred), wipes it on both sides with a wet sponge, and then wraps it up carefully in a piece of ordinary white wrapping paper, allowing the package to be sealed and corded ad libitum. Notwithstanding all the precautions used, a message appears on the slate. It is accomplished in this way. A message in reverse is written on the wrapping paper with a camel’s hair brush or pointed stick, dipped in some sticky substance, and finely powdered slate pencil dust is scattered over the writing. At a little distance, especially in a dim light, it is impossible to discover the writing as it blends very well with the white paper. In wrapping up the slate the medium presses the writing on the paper against the surface of the slate and the chirography adheres thereto, very much as the greasy drawing on a lithographer’s stone prints on paper.