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Rh that they often forget that the study will give them that very knowledge, and that, properly pursued, it is the best possible introduction to psychology in general. Every chapter in the present book, he says, is an attempt to organize the knowledge already possessed by those who know little or nothing of scientific psychology, and to assist them to inquiries which will give a clearer apprehension of the nature and possibilities of the child. The treatise begins with the wakening of the child to conscious life through the senses, the nature and workings of each of which are described. The bridge over from the physical to the mental is found in consciousness, which for the present purpose is defined as the self knowing its own states or activities. The idea of identity and difference arises, symbols are invented or suggested, and language is made possible. The features of language peculiar to children are considered. Muscular or motor control, the feelings, and the will are treated as phases or factors in development, and their functions are defined. The intellect and its various functions are discussed with considerable fullness; and chapters on The Self, Habit, and Character; Children's Instincts and Plays; Manners and Morals; Normals and Abnormals; and Stages of Growth, Fatigue Point, etc., follow. A very satisfactory bibliography is appended.

The Discharge of Electricity through Gases is an expansion of four lectures given by the author, Prof. J. J. Thomson, of the University of Cambridge, at Princeton University in October, 1896. Some results published between the delivery and printing of the lectures are added. The author begins by noticing the contrast between the variety and complexity of electrical phenomena that occur when matter is present in the field with their simplicity when the ether alone is involved; thus the idea of a charge of electricity, which is probably in many classes of phenomena the most prominent idea of all, need not arise, and in fact does not arise, so long as we deal with the ether alone. The questions that occur when we consider the relation between matter and the electrical charge carried by it—such as the state of the matter when carrying the charge, and the effect produced on this state when the sign of the charge is changed—are regarded as among the most important in the whole range of physics. The close connection that exists between chemical and electrical phenomena indicates that a knowledge of the relation between matter and electricity would lead to an increase of our knowledge of electricity, and further of that of chemical action, and, indeed, to an extension of the domain of electricity over that of chemistry. For the study of this relation the most promising course is to begin with that between electricity and matter in the gaseous or simpler state; and that is what is undertaken in this book. The subject is presented under the three general headings with numerous subheadings of The Discharge of Electricity through Gases, Photo Electric Effects, and Cathode Pays.

For a clear and concise presentation of the framework of psychology and its basal truths, the Story of the Mind may be commended. Although the space afforded is only that of a bird's-eye view, no skeleton bristling with technical terms confronts us, but an attractive and well-furnished structure with glimpses of various divisions that tempt us to further examination. The text is simply and charmingly written, and may induce many to search the recesses of psychology who, under a less skillful guide, would be frightened away. A bibliography at the end of the volume supplies what other direction may be needed for more advanced study. Admirable in construction and treatment as the book is, there are, however, paths in which we can not follow where Professor Baldwin would lead, and in others that we undertake with him we do not recognize our surroundings as those he describes. This is especially the case with the environment of the genius. We do not find that "he and society agree in regard to the fitness of his thoughts," nor that "for the most part his judgment is at once also the social judgment." If such were the case, how would he "wait for recognition," or be