Professor Zöllner, the most famous victim of the bold medium, lacked entirely the necessary critical faculty, and became an easy prey of fraud. One of his colleagues, a professor of surgery in the University of Leipsic, had entered upon a bet with Professor Zöllner that a slate carefully sealed and watched by himself could not be written upon by spirits; he had left the slate in Professor Zöllner’s hands in the confidence that the latter would use all necessary precautions. Professor Zöllner, however, not finding Dr. Slade at home, saw nothing wrong in leaving the sealed slate at the medium’s residence and thus allowing it to pass for an indefinite time out of his own control, thinking that the seals were a sufficient protection. It goes without saying that his colleague at once cancelled the bet and took no more interest in the experiment. {xxvii} The foot and hand prints which Dr. Slade produced were apparently made from celluloid impressions, which could easily be carried about and hidden in the pocket. This explains why these vestiges of the spirit were not of the size of Dr. Slade’s hands or feet. Mr. Willmann calls attention to the fact that the footprints, as published by Professor Zöllner, were made from feet whose stockings had been removed but a few moments before, for they still show the meshes of the knitting which quickly disappear as soon as the skin of the foot grows cold. Professor Zöllner did not see such trifles, and yet they are important, even if it were for the mere purpose of determining whether the spirits wear stockings made in Germany or America. * * * * * The accounts of travelers are, as a rule, full of extravagant praise of the accomplishments of foreign magicians; thus, the feats of our American Indians are almost habitually greatly exaggerated. The same is true in a greater measure of fakirs and Hindu magicians. Recent accounts of a famous traveler are startling, but the problem is not whether or not what he tells is true (for only a little dose of good judgment is sufficient to recognize their impossibility), but whether or not he believes his tales himself. The problem is neither physical nor historical as to the reality of the events narrated; the problem is purely psychological as to his own state of mind.