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Rh assumptions. It conceives the ancient ice sheet as formed thus: From many groups of mountains there radiate glaciers which meet and unite, but do not entirely lose their individualities. Each may be traced in its course by the nature of the stones which it carries, and the furthest advance of each will be marked by a terminal moraine. These glaciers would frequently form lakes by damming rivers, and the lakes would make deposits which must be distinguished from those dropped by the ice. The former he calls bowlder clay and the latter till. Many earlier theories and beliefs are vigorously shaken up in these notes. In the freely expressed opinions jotted down, in its evidence of the forming and abandonment or modification and development of views, this volume has a peculiar value that a finished treatise would not have. The investigator who would carry this subject forward should read the posthumous contribution of Prof. Lewis carefully and often.

the dozen or so of lectures and addresses which Prof. Thorpe has gathered into this volume he tells how most of the great chemical discoveries of the past two hundred and fifty years have been made, and gives us an acquaintance with the personalities of the men who made them. The lectures are arranged in historical sequence, the first sketching the life and work of Rob. ert Boyle, and the others dealing successively with Priestley, Scheele, Cavendish, Lavoisier, Faraday, Graham, Wöhler, Dumas, Kopp, and Mendeleeff. In this volume we may read how oxygen and the composition of water were discovered, and what were the respective shares of Priestley, Cavendish, and Lavoisier in these discoveries; how Wohler broke down the barrier between organic and inorganic chemistry, and how the wonderful Russian, Mendeleeff, evolved the periodic arrangement of the elements. We may, moreover, learn also that Cavendish was intensely shy, a hater of noise and bustle, and had a house made up of laboratories and workshops, very little of it being set apart for personal comfort; that when young Faraday was traveling on the Continent as amanuensis to Sir Humphry Davy he wrote of Lady Davy, "Her temper makes it oftentimes go wrong with me, with herself, and with Sir Humphry," and similar interesting facts about the other men included in the volume. The lectures have been delivered as occasion has called them forth, to a variety of audiences, and the author is far from claiming that they constitute a history of the time from Boyle to the present day.

inquiry for a syllabus of sociological method printed in 1889 by one of the authors of this manual furnished surprising evidence of demand for scientific exposition of social relations. The interest in philosophical sociology has continued to increase in this country. Since the organization of the Department of Sociology in the University of Chicago applications for information about a suitable text-book of the subject have been incessant. No such text-book existing, this manual has been prepared as a guide to the elementary study. It does not presume to be a contribution to sociological knowledge or a report of research on the material of social knowledge, but a help in the training of beginners, the proposal of a method of preliminary investigation, a "laboratory guide"; the outgrowth of experience in teaching sociology under difficulties. It aims to commend a method that shall emphasize the necessity of precise knowledge of social facts, and shall confirm students in the habit of widening their comprehension of particulars by relating them to the containing conditions. The first book, on the Origin and Scope of Sociology, starts with the beginnings of the science, and goes on to treat of its development, its relation to the special social sciences and to social reforms, and of the organic conception of sociology. The second book, on the Natural History of a Society, takes the family, composed of the man and his newly married wife going to open a farm and settle on the native, solitary prairie, and traces the gradual growth of the community through the increase of the family, the accession of new settlers, the beginning of