The method which Kellar used, and which he described to me, was this. With the consent of the owner of the hotel, whom he agreed to pay for any damage, he had a small trap made in the floor of the room, about as large as a hot air register, with the necessary means of opening and closing it. A plush rug with rectangular designs was placed over this trap, and one of the designs, which was just the size of the trap, was cut out with a razor, these cuts being imperceptible. The piece of rug was glued firmly to the top of the trap. In addition to these preparations, Kellar bought a specimen of every variety of slate to be found in the downtown section of Philadelphia. When the time for the “seance” arrived, Barney, Kellar’s clever young assistant, was seated on a platform in the room underneath the trap with the assortment of slates by his side. As soon as the Commission was seated around the table he opened the trap and could then hear all that was said in the room above. When the exhibition commenced he simply took the slate Kellar put under the table leaf, selected one from his assortment to match it, wrote on it the answer, and then slipped it under Kellar’s fingers. In the case of a marked slate he used that instead of a duplicate. Of course it was perfectly easy for Kellar to do his part without removing his thumb from the top of the table. “A fake, pure and simple, you will say,” Kellar remarked to me, and then added, “but that’s what all Spiritualistic manifestations are.” In point of time John W. Truesdell was probably the first exposer of Slade as he investigated him as early as 1872, but the results of his investigation were not made public until he published his book, “Bottom Facts,” in 1883. In this book he tells of setting a trap for Slade and proving that he substituted slates. As Sam Johnson of Rome, N. Y., Truesdell arranged for a seance with Slade. Knowing that his overcoat would be searched, he left it hanging on the hall rack with an unsealed letter in the pocket and while waiting in the Spirit room he made the most of his opportunity to look around. Under the sideboard he found a slate with a message written on the lower side which read: “We are happy to meet you in this atmosphere of Spirit research. You are now summoned by many anxious friends in the Spirit life, who desire to communicate with you, but who cannot until they learn more of the laws which govern their actions. If you will come here often, your Spirit friends will soon be able to identify themselves and to communicate with you as on earth life. “Allie.” In a bold hand Truesdell added: “Henry, look out for this fellow. He is up to snuff. “Alcinda.”