Page:Popular Science Monthly Volume 50.djvu/428

412 phases of human thought and emotion which literature records, how are these to be secured and developed save through a careful cultivation of the language sense?

It might not be impossible, we think, through a proper setting forth of this aspect of the case, if not to stem the rising tide of illiteracy, to engage the interests and the sentiments of a respectable minority in favor of such a study of the English language and its literature as should confer the benefits we have mentioned. The word culture has been much abused, but it has a meaning with which we can not dispense; and, as an instrument of culture—of genuine emancipation and elevation of mind—there is no line of study which we can place before that which raises a mind fairly to the level of a great language and a great literature.



query that Prof. Trowbridge takes as the title of his recent book is one of the most difficult to give a direct answer to that have been propounded to modern science. The answer given in this volume presents electricity to the adult reader from a much different point of view than was afforded by the treatise of his school or college days—say, ten to thirty years ago. Our author has designed his book to give a popular presentation of Maxwell's theory of the electro-magnetic origin of light and heat, for he holds that by studying the transformations of energy involved in this theory we can obtain the best idea of what electricity is. The plan of the volume is to treat in successive chapters the leading phases of the subject as illustrated by important processes or pieces of apparatus. In the short chapter on measurements in electricity he shows that gravitation is used to measure all our electrical manifestations, and then passes to a discussion of the nature of gravitation itself. In dealing with magnetism he quotes the expressions of Franklin and his contemporary, Prof. Winthrop, on this subject, and some of Count Rumford's views on the transformation of energy—a subject that bears a fundamental relation to the modern science of electricity. Passing to later times, he shows that it is to considerations of the nature of the surrounding medium that we owe the chief advances in our knowledge of magnetism. His account of the dynamo machine begins with a comparison of Faraday's galvanometer with one of the present day. This is followed by a description of the construction of a simple piece of apparatus by means of which the essential features of the dynamo can be explained. Subjects of other chapters are: Alternating Currents, Transmission of Power by Electricity, The Leyden Jar, Step-up Transformers, The Electro-magnetic Theory of Light and the Ether, The X Rays, and The Sun. The book is popular but not elementary. The treatment is everywhere philosophical, though by this we are far from meaning