With the Crewe Circle I have had so many tests that it is difficult to select the most stringent. As the well-known Price case of alleged fraud bears on the question of the substitution of dark slides, the following case may be of interest. On this occasion the substitution of dark slides was impossible, for the simple reason that no dark slides were used. Saying nothing to the members of the Circle beforehand, I took with me to Crewe on November 12th, 1921, a loaded box camera containing six specially-marked plates of a size smaller than those usually employed in experiments of this nature. All that Hope and Mrs. Buxton did was to arch their hands over this magazine camera whilst one of them flicked the shutter-catch. Photographic readers will realise that it is impossible to tamper with the plates in a box camera, in daylight, without spoiling the lot. To enable the “power” to flow from Mr. Hope on to the plates, the controlling intelligence stipulated that Mr. Hope should be allowed to take hold of my right wrist as I dropped each plate into the developer. Psychic effects were secured on two out of the six plates under conditions which, I am convinced, rendered deception impossible. I have been told that Mr. Hope must have printed the effects on to the plates by flashlight whilst he had hold of my wrist. If the critic derives any comfort from believing that this actually occurred he is welcome to his belief! In another evidential case is that already mentioned by Sir Arthur Conan Doyle of an experiment conducted by two photographic members of the S.S.S.P. and myself at Crewe. In this case the camera and slides employed were brand new and were not examined by the sensitives until after the sitting. The dark slides differed from those usually employed by the sensitives. Neither Mr. Hope nor Mrs. Buxton was in the dark room for loading the slides or for developing the plates. The central face of three supernormal faces secured on this occasion is an undoubted likeness of the father of one of the sitters. The result was absolutely conclusive to my friends and myself. We emphatically declare that under the circumstances trickery was impossible. [Illustration: FIG. 20.—Psychograph in the handwriting of Mr. Wm. Walker obtained at Crewe on July 28th, 1922. Compare with normal handwriting shown in Fig. 21. (_See_ p. 88.)] [Illustration: FIG. 21.—Portion of letter written by Mr. Wm. Walker during his lifetime for comparison with psychograph Fig. 20.] [Illustration: FIG. 22.—Mr. S. Maddocks, Hon. Sec. of the Sheffield and District S.P.R., with psychic photograph of his first wife. Compare with Fig. 23. (_See_ p. 113.)] [Illustration: FIG. 23.—Photograph of Mr. Maddocks’ first wife for comparison with Fig. 22.]