Dr. Moll's latest book, “Der Rapport in der Hypnose,” is published under the auspices of the German Society for Psychological Research. This Society, we might add, was formed in November, 1890, by the amalgamation of the “Psychological Society” of Munich, and the “Society for Experimental Psychology” of Berlin, and corresponds, in a more sceptical sense, to the “Society for Psychical Research” in this country. A knowledge of the above fact explains at once the standpoint from which the question is approached. It is well known that the purpose of the societies mentioned is to investigate impartially all kinds of phenomena brought under their notice, and not a priori to reject such phenomena as impossible. In the same way Dr. Moll has taken in hand the assertion of the so-called mesmerists, that in the hypnotic rapport there is at work some kind of unknown influence, which cannot be appreciated by our generally recognized senses, and which they call animal magnetism; and he has considered it worth the trouble of making a great number of experiments in order to test the influence of animal magnetism in and on the hypnotic condition, especially in producing the so-called rapport. The last number of this Journal contained a review of an article by Professor Wundt on hypnotism, in which the question of animal magnetism, telepathy, etc., is rejected without experimental investigation as a scientific impossibility. To this article Dr. Moll refers at the end of his book, saying that Professor Wundt was not quite correct in stating that only those give their time to experiments of the kind mentioned, who thoroughly believe in the phenomena they are going to investigate, for it is almost needless to say that Dr. Moll comes from his experiments to the same conclusions at which Professor Wundt arrives without experiments, through scientific reasoning. Professor Wundt's standpoint is very good for the limited number of those who are so well-informed in science as is the Leipzig Professor himself, and able absolutely to follow the course of his logic, but the standpoint adopted by the societies mentioned, and also by Dr. Moll, is certainly the more suitable and practical one for convincing the greater number of people of the erroneousness of the assertion that there is such an invisible and powerful factor at work in hypnotic suggestion as “animal magnetism.” The latter standpoint also avoids the objection of unfairness from the opposite side. It is almost superfluous to say that the number and variation of the experiments which Dr. Moll performed and describes is as complete and thorough as we have become accustomed to expect from Dr. Moll's former work. His knowledge of the subject and of the related branches is very wide, and to us it was especially interesting to read his remarks on the taming of wild beasts, and the conclusions he draws from the analogy of the influence of the dompteur on his animals and Of the hypnotizer on the person with whom he is en rapport. We doubt whether Dr. Moll's latest book will find so wide a circle of readers as his book on “Hypnotism” has found. Hypnotism in itself is so interesting that such an excellent book as the one mentioned could not fail to find a large circulation. It is, however, not everybody's liking to read about experiments which all prove to be failures, i.e., to find a record of negative results only. The greater number of people—and this is certainly true in the case of a large number of those who are interested in hypnotism, and to this latter class alone the remark of Professor Wundt applies—in performing or witnessing experiments, expect and want to see positive results, and are unable to appreciate that the failure of an experiment is quite as valuable from a scientific point of view as a successful experiment. Dr. Moll's “Rapport in der Hypnose” is a collection of negative results with regard to the proof of the existence of animal magnetism, and therefore of great scientific value, although not to medical hypnotizers, who knew them already.