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126 past. To take the present subject as an illustration, from the division of functions that has taken place in the past we may infer a still further specialization in the future. Higher achievements in the several professions may be expected as a result of this process, the men of different professions will become more and more necessary to one another, and the solidarity of society will be increased.

The Professional Institutions will form the last portion but one of the only volume remaining uncompleted in Mr. Spencer's systematic series of philosophical works. It therefore makes probable the successful completion of the series, and, together with the division on Industrial Institutions which is to follow, will be sure to throw much light upon the puzzling industrial problems of the day. A few days ago Mr. Spencer completed three quarters of a century of life and about half a century of productive labor in the field of thought. For twenty years past there have been times when the close of his labors seemed imminent, but, mainly as a result of prudent care, his physical strength has lasted till this time, while the articles of which we print the first this month adequately demonstrate that his mental grasp and acumen are in no wise impaired.



Great Ice Age, when it appeared in 187*7, took a position at once as one of the standard treatises in geological science. It has held that place ever since, although the department of geology with which it is concerned has been more actively and scrutinizingly studied, perhaps, than any other. With so much research as has been bestowed upon glacial phenomena, much knowledge has been accumulated that was not within the author's reach eighteen years ago, and some new views have prevailed; yet Prof. Geikie's arguments so ably set forth in the first edition of his work have not lost their force, and his main conclusions have not been successfully assailed in their essentials. A revision of the book had, however, become necessary, in order that it might enjoy the benefit of the acquired knowledge, and that the new views might receive just discussion and the old ones be re-examined in the light of them. Yet in the immense bulk of the literature that has accumulated, and its scattered condition among many nationalities and in multitudes of periodicals and monographs, the author has not attempted to discuss all the interesting questions mooted and canvassed in it, but, to keep his sketch within reasonable limits, has been compelled to follow more or less strictly the lines laid down in the first edition, in which his endeavor was represented to be to give a systematic account of the Glacial period, with special reference to its climatic conditions. All the more important features of the evidence, however, have been considered, and few references are given to original sources of information. The chapters dealing with the phenomena of existing glacial action in Alpine and arctic regions have been touched up, and the glacial geology of Scotland has been thoroughly revised. Some rearrangements of other matter have been made; but nearly three fourths of the volume have been entirely rewritten. The glacial and interglacial deposits of the European continent are treated more fully than was possible ten or fifteen years ago. The purpose of the book being to sketch the present position of glacial geology rather than to write the history of its rise and progress, no great notice has been taken of the opinions held by its pioneers. In dealing with questions still under discussion the author has endeavored to avoid a controversial tone, preferring as a rule to set forth the evidence as clearly and impartially as he could, and then to point out what seemed the most reasonable interpretation. To avail himself as fully as possible of the results of 