The points of light gave place to clouds of luminous mist like softly rolling, utterly silent globes of dull blue light. Little by little the dance of the globes speeded up. They spun and whirled and wove in and out among themselves till they had drawn into one mass all the luminous matter in the room. Like a terror-charged cloud this mass hovered some eight feet high, a clear two feet off the floor; its brilliance waxed and waned and its confines drew in. Slowly the cloud was taking shape as a pillar and within the pillar one could see the ghastly shaping of the rudimentary form. Here before my eyes was the actual form of the stranger--for this ghost is a malevolent strangling demon--on the very point of concentration. Carefully I stretched out my hand to the leaden box, unscrewed the cylindrical lid, and threw into my right hand the precious vial of radium salt. The energy-charged tube glowed in the dark with all the beauty of intense phosphorescence, and as I held it at arm’s length toward the pillar of semi-materialization that represented all the evil forces of discarnate Hate--_the mists of vapour rolled away. As if by magic the whole apparition was dissipated_, and in twenty seconds was as if it had never been. There is little more to be said. The theory had been brilliantly vindicated in practice, but it is impossible to generalize from one particular instance. Physicists know the wide range of differences that exist between the different radium salts,[20] and there the matter must rest until opportunity for further experiments is available. The analogous protective vibrations that the author of the monograph alleges would work are all probable, but require considerably more apparatus. To my mind the use of radioactive salts as talismans with which to exorcise a case of malignant haunting is at once a great and practical step in the direction of relieving humanity of these troublesome psychic intruders. The discovery and the theory are one of the most remarkable contributions to psychic science in our time. Pitchblende, from which radium is extracted, does not appear to have attracted the attention of the ancients and there is no trace of its use in any process of alchemy or the allied sciences. Dr. Dee’s magic mirror is reported to have been of a black substance and it is possible that it may have been of radioactive material, although this quality is not necessary for the purposes for which he required it.[21]