The Earth as Modified by Human Action | Page 2

will to which he has reduced other forms of terrestrial surface.
Besides these old and comparatively familiar methods of material improvement, modern ambition aspires to yet grander achievements in the conquest of physical nature, and projects are meditated which quite eclipse the boldest enterprises hitherto undertaken for the modification of geographical surface.
The natural character of the various fields where human industry has effected revolutions so important, and where the multiplying population and the impoverished resources of the globe demand new triumphs of mind over matter, suggests a corresponding division of the general subject, and I have conformed the distribution of the several topics to the chronological succession in which man must be supposed to have extended his sway over the different provinces of his material kingdom. I have, then, in the introductory chapter, stated, in a comprehensive way, the general effects and the prospective consequences of human action upon the earth's surface and the life which peoples it. This chapter is followed by four others in which I have traced the history of man's industry as exerted upon Animal and Vegetable Life, upon the Woods, upon the Waters, and upon the Sands; and to these I have added a concluding chapter upon Man.
It is perhaps superfluous to add, what indeed sufficiently appears upon every page of the volume, that I address myself not to professed physicists, but to the general intelligence of observing and thinking men; and that my purpose is rather to make practical suggestions than to indulge in theoretical speculations more properly suited to a different class from that for which I write.
GEORGE P. MARSH.
December 1, 1868.

PREFACE TO THE PRESENT EDITION.
In preparing for the press an Italian translation of this work, published at Florence in 1870, I made numerous corrections in the statement of both facts and opinions; I incorporated into the text and introduced in notes a large amount of new data and other illustrative matter; I attempted to improve the method by differently arranging many of the minor subdivisions of the chapters; and I suppressed a few passages which teemed to me superfluous. In the present edition, which is based on the Italian translation, I have made many further corrections and changes of arrangement of the original matter; I have rewritten a considerable portion of the work, and have made, in the text and in notes, numerous and important additions, founded partly on observations of my own, partly on those of other students of Physical Geography, and though my general conclusions remain substantially the same as those I first announced, yet I think I may claim to have given greater completeness and a more consequent and logical form to the whole argument
Since the publication of the original edition, Mr. Elisee Reclus, in the second volume of his admirable work, La Terre (Paris, 1868), lately made accessible to English-reading students, has treated, in a general way, the subject I have undertaken to discuss. He has, however, occupied himself with the conservative and restorative, rather than with the destructive, effects of human industry, and he has drawn an attractive and encouraging picture of the ameliorating influences of the action of man, and of the compensations by which he, consciously or unconsciously, makes amends for the deterioration which he has produced in the medium he inhabits. The labors of Mr. Reclus, therefore, though aiming at a much higher and wider scope than I have had in view, are, in this particular point, a complement to my own. I earnestly recommend the work of this able writer to the attention of my readers.
George P. Marsh
Rome, May 1, 1878.

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----Elements de Physique