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260 due to his own steady and powerful advocacy all geologists are aware; but he gracefully reminds us that we also owe much to the labors of those American geologists who have found in the Western Territories such convincing instances of the work of denudation in shaping the surface." The first part of the book, comprising the lectures, deals with land-sculpture in general, and describes the working of Nature's sculpturing tools. The reader is then taken in succession to the different characteristic regions in the country and shown in detail, with much wealth of illustration, how the hills and valleys and salient features have been wrought out. The subject could very well be treated in such a manner as to make the presentation of it formal and dry in the extreme; but, says Mr. Green, the author "knows and loves his fatherland too well to look upon it merely as the object of geological research. Legend and history, old ballads and modern poetry, have all been pressed into his service, and he interweaves into his narrative allusion and quotation in a way that enlivens even the most technical parts of the volume. The chapter on The Influence of the Physical Features of Scotland upon the People shows well what a vast amount of human interest attaches even to so special a science as geology."

Prof. Geikie himself predicted in an address before the Geological Society of Edinburgh, in 1873, for the future of his theory: "Of one thing I feel surely confident: When the din of strife has ceased and men come to weigh opinions in the dispassionate light of history, the profound influence of the Huttonian doctrines of the present time on the future course of geology will be abundantly recognized. By their guidance it will be possible to reconstruct the physical geography of the continents in successive ages back into some of the earliest periods of geological history."

Prof. Geikie's theory is further elaborated and applied in his five lectures, delivered at the Royal Institution, in 1884, on The Origin of the Scenery of the British Isles. In these lectures the author held that "the present surface of Britain is the result of long, complicated processes in which underground movements, though sometimes potent, have only operated occasionally, while superficial erosion has been continuous so long as any land has remained above the sea. The order of appearance of the existing features is not necessarily that of the chronological sequence of the rocks. The oldest formations have all been buried under later accumulations, and their re-emergence at the surface has only been brought about after enormous denudation." The lectures conclude with an indication of the connection between the scenery of a country and the history and temperament of its people. This subject was considered from four points of view, the influence of landscape and geological structure being traced in the