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564 considered the question of how minerals are combined and distributed so as to build up the earth's crust; attention is here especially directed to the knowledge of rock structure gained within recent years by the use of the microscope.

Part III treats in turn of the sedimentary and the eruptive rocks. Of the former, the original structure, the association of strata, the chronological value of strata, etc.,. . . are reviewed; in connection with the latter, the formation of mineral veins—by deposition from the molten state and by deposition from water-solution—is described.

Fossils, which may be termed "the labels of the strata," receive the share of attention due their importance, and are studied as indicating former changes in geography, former conditions of climate, and the chronological sequence of geological formations.

The rest of the book is given to the study of the main divisions of the geological record—that is to say, to a systematic review of the stratified formations of the earth's crust.

An appendix, furnishing an outline of the classification of the vegetable and the animal kingdom will prove convenient for reference, and the many illustrations embodied in the text of the volume will be a welcome aid to the student.

is essentially a book on political economy, the substance of which was first put together, more than twenty years ago, by way of using the experience of a man of business in the education of his children. It was afterward recast and delivered as lectures, and then printed. Having become out of print, it has been entirely rewritten, as a text-book—and with especial reference to some of the economic questions of the day. The principles of the subject, in its several departments, are presented in brief, pointed paragraphs, which are often short enough to be maxims. Considering the situation of workmen, the author deplores subjection alike to capital and to the trades union; and advises workmen to try to make themselves independent by getting a year's subsistence ahead. This is not beyond their means, for thousands of the class are daily paying the price of it from means drawn wholly from weekly wages.

contents of this volume are briefly summarized by the author as consisting, first, of a detailed description of the various laboratory class processes from the first lesson to the last in the three years' course of study at the Chicago Manual Training School. The second division is "an exhaustive argument a posteriori and a fortiori in support of the proposition that tool-practice is highly promotive of intellectual growth, and in a still greater degree of the up-building of character." The third division deals with the history of civilization as related to methods of education, and in the fourth part the history of manual training as an educational force is briefly presented.

of stories of artist-life, to which an allegorical air is given by the characters bearing the name of artists' colors. According to its motto, the book is without moral or purpose, but "whichever way you look" in it, "you'll only find—a pair of lovers."

present volume does not profess to be a complete or exhaustive history of astronomy during the period covered by it. Its design is to present a view of the progress of celestial science on its most characteristic side since the time of Herschel." These words, taken from the preface, clearly present the scope and aim of the book before us.

The introduction refers briefly to the three kinds of astronomy distinguished. The first of these is known as observational or practical, the second is called