“In order to gain the perfect, full confidence of Dr. Slade, and to have him give a seance in my home, and in order to counteract and overcome his explicit aversion as to do writing on or between a sealed slate or a locked book—I showed him letters from (two eminent and confiding Spiritist Authors)—Dr. Heinrich Tiedemann and Tiedemann’s intimate friend Hudson Tuttle, promising to me that they would be present at that seance (at 148 Fairmount Avenue).
“Dr. Slade had handled and inspected that Book and Slate, during a Seance, at my residence (at 148 Fairmount Avenue, Phila., Pa.), where I, together with Mr. Wertheimer (then a student of Jurisprudence)—and in presence of other witnesses (who were concealed and not seen, nor suspected by Dr. Slade, nor his ‘Spirits’) detected the manipulations, pedalations (foot, leg and other bodily movements)—and the general modus operandi of his simple Legerdemain at the seance. I had ready, for that seance, three different suites of Furniture, and thus, I found out that he would, or could, perform only at, or on a certain kind of plain, square or drop-leaf table and ordinary wooden chairs or cane seat chairs.
“Each person present at the Seance, wrote, independent of and before communicating with, the others, a personal, individual report of the Seance and signed it within the next few days. A day or two after, I put these papers in my pocket and also another paper I had prepared, to serve or use as Dr. Slade’s confession to be signed by him. I went to the Girard Hotel, Room 24 (N. W. corner of 9th and Chestnut Streets, Philadelphia, Pa.), to have Dr. Slade arrested for obtaining money under false pretense,—or to get him to sign his own confession. There, in his room, No. 24, in the Girard Hotel, I had another, a different Seance, with Dr. Slade. He again carefully scrutinized the book and the slate, and then, holding the book under the table, secretly and carefully, attempted to open the lock, with a small key, hidden in his handkerchief.
“Dr. Slade and his pretended ‘Spirits’ could not write in the book. While holding it under the table, he attempted to pull out of the book that thin, wooden, square frame, I had put there at the edges of the leaves so that the small piece of lead pencil could move about.—Then, in a similar attempt, he worked and perspired, on, and over the double slate. His ‘Spirits’ could not write in the locked slate and he could not open it.
“He said, ‘The Spirits seem to be angry at your skepticism, it’s no use to lose more time by trying. My guide don’t want to have anything more to do with you.’
“Then upon Dr. Slade’s request I unlocked the slate, and he wrote in the ordinary way, as writing generally is done in schools, two short sentences in the slate. Then he worked the sponge,[70] and turning the written on side downward, sleight-of-hand trick, tried to palm this off, claiming that this is ‘Genuine, independent, Spirit slate writing.’
“Up to this time, November the 4th, 1882, I had shown to Dr. Slade friendly, joyful attentiveness. We talked about some of my newspaper articles I had published some weeks before he consented to give me a seance.
“In these newspapers I had described him (Dr. Slade) as ‘The Modern Cagliostro, a celebrated necromancer, martyr or a charlatan, of radical free-religious proclivities, fine manners and a humistic, witty and forceful public lecturer and most powerful Spiritistic Medium, who again and again has been and is challenging exposures, and calling special attention to the fact that Dr. Slade has, in his lectures, and otherwise, again and again publicly announced that he is prepared to pay a thousand dollars ($1000.00) to any person that can prove that he (Dr. Slade) is a humbug, or that Dr. Slade’s “manifestations” are trickery, legerdemain, humbug or in any way fraudulent.’
“LOCKED SLATE” USED BY DR. HENRY SLADE IN HIS WRITING TESTS AT PHILADELPHIA