I was offered house property in exchange for the right to exhibit the ghost and a full description of the apparatus on attendance at the Polytechnic to see how things were manipulated. I publish one of the most amusing letters, which has no address or proper signature, but only the initials “R. C.”:— “Whereas the directors and managers of the Polytechnic Institution believe and maintain the phenomenon called ‘spirit-rapping’ to be produced by trickery, jugglery, or some natural agency, and to be an imposture, I, the undersigned, on the contrary maintain that there is some non-human agent which moves the tables, chairs, etc., and carries on an intelligent conversation with spectators by knocking, or tilting, or other signs. I am ready to wager from £5 to £50 with any one who chooses to accept my challenge that the phenomenon shall take place, and that no one present shall be able to detect any sort of trickery or jugglery in the matter. It is to be clearly understood that mere opinions that the thing is done by natural agency are to go for nothing. The natural agency _must be proved_. On the other hand I defy any one to produce the same phenomenon by natural agency _without my being able to detect that agency_. In making this proposal I wish it to be distinctly understood that I do not place any trust or confidence in the so-called ‘spirits,’ as I maintain, in opposition to the whole body of so-called ‘spiritualists,’ that the intelligent agent which moves the tables, chairs, etc., and converses and answers questions by knocking, is nothing more or less than _the evil spirit_ which dwells in humanity, and is found in every human being. This proposition can be clearly demonstrated. As to the so-called ‘spirits’ being the ‘souls of the dead,’ the idea is absurd, and this absurdity also can be made abundantly manifest. This spiritualism is doing an immensity of mischief, and ought to be exposed, but it will never be exposed if people shut their eyes _to the fact_. It will not be the less a fact, and will not the less impose on all who witness it, because there are men and women who _predetermine_ in their own minds that it cannot be true, and refuse to be convinced _by either their senses or their understandings_. In all ages there have been deaf adders whom no music could charm, and there are in these days also many ‘who having eyes will not see, and who having ears will not hear.’ _On what grounds_ does any one assume as a certainty that such a thing is impossible? “RICHARD CRUIN.”