Concerning the competence of Mr. Wallace himself to weigh, unbiassed, the evidence which comes before him, it suffices to cite the case of Eusapia Paladino, a Neapolitan "medium," who, in the words of one of her most ardent dupes, became "the unexpected instrument of driving conviction as to the reality of psychical manifestations by the invisible into the minds of many scientists." A number of distinguished savants testified to the genuineness of the woman's performances in Professor Richet's cottage on the Ile Roubant in the autumn of 1893. It was the serious and complete conviction of all of them (Lodge, Richet, Ochorowicz, and others) that "on no single occasion during the occurrence of an event recorded by them was a hand of Eusapia's free to execute any trick whatever." Mr. Maskelyne, such testimony notwithstanding, declared that the whole business was "the sorriest of trickeries," and, to the credit of the Society for Psychical Research, it undertook the expense of bringing Eusapia to England for the purpose of testing the genuineness of her doings. She was taken to a house in Cambridge, and detected as a vulgar impostor. Yet Mr. Wallace, in the new edition of his Miracles and Modern Spiritualism, describes all the phenomena occurring at Professor Richet's house as "not explicable as the result of any known physical causes," and, in a subsequent explanatory letter to the Daily Chronicle of 24th of January, 1896, expresses the opinion that "the Cambridge experiments, so far as they are recorded, only prove that Eusapia _might_ have deceived, not that she actually and _consciously_ did so." The integrity of Mr. Wallace is not to be doubted, but what becomes of his competence to judge when prejudice blinds itself to facts? Spiritualism, _if true_, demonstrates this and that about the unseen; but spiritualism, _proved to be untrue_, lacks half the dexterity of an astute conjurer, and the whole of his honesty. Every scientific man recognises the doctrine of the Conservation of Energy as a fundamental canon. But with those who regard the phenomena of Spiritualism as "not explicable" except by supernatural causes, it would seem that that doctrine, as also the not unimportant conditions of Time and Space, count for nothing. When we read their reports of the behaviour of mediums who project (of course, in the dark) "abnormal temporary prolongations" like pseudopodia, we should feel alike depressed and confounded were there not abundant proofs what wholly untrustworthy observers scientific specialists can be outside their own domain. As the writer has remarked elsewhere, minds of this type must be built in water-tight compartments. They show how, even in the higher culture, the force of a dominant idea may suspend or narcotize the reason and judgment, and contribute to the rise and spread of another of the epidemic delusions of which history supplies warning examples.