At the late meeting of the British Association in Edinburgh, Dr. Thomson rather startled the scientific world by an address delivered in the Biological Section, in which he characterised the so-called new science of spiritualism as the invention of impostors and mountebanks. His address, which lacked the author's constitutional caution and discretion, was severely handled in several of the leading journals, and a trenchant pen, in an Edinburgh cotemporary, "cut up rough" with a vengeance. Among others who replied to Dr. Thomson's strictures was Dr. Robert H. Collyer, of London, who claims to be the original discoverer of electro-biology, phreno-magnetism, and stupefaction, by the inhalation of narcotic and anaesthetic vapours. In the course of his address, Dr. Thomson spoke as follows:--"It must be admitted that extremely curious and rare, and to those who are not acquainted with nervous phenomena, apparently marvellous phenomena, present themselves in peculiar states of the nervous system--some of which states may be induced through the mind, and may be made more and more liable to recur, and greatly exaggerated by frequent repetition. But making the fullest allowance for all these conditions, it is still surprising that persons, otherwise appearing to be within the bounds of sanity, should entertain a confirmed belief in the possibility of phenomena, which, while they are at variance with the best established physical laws, have never been brought under proof by the evidences of the senses, and are opposed to the dictates of sound judgment. It is so far satisfactory in the interests of true biological science that no man of note can be named from the long list of thoroughly well-informed anatomists and physiologists, who has not treated the belief in the separate existence of powers of animal magnetism and spiritualism as wild speculations, devoid of all foundation in the carefully-tested observation of facts. It has been the habit of the votaries of these systems to assert that scientific men have neglected or declined to investigate the phenomena with attention and candour; but nothing can be farther from the truth. From time to time men of eminence, and fully competent, by their knowledge of biological phenomena, and their skill and accuracy in conducting scientific investigation, have made the most patient and careful examination of the evidence placed before them by the professed believers and practitioners of so-called magnetic, phreno-magnetic, electro-biological, and spiritualistic phenomena; and the result has been uniformly the same in all cases when they were permitted to secure conditions by which the reality of the phenomena, or the justice of their interpretation, could be tested--viz., either that the experiments signally failed to educe the results professed, or that the experimenters were detected in the most shameless and determined impostures." This sentence fell among the _savants_ like a bomb, and