Mr. _Russell_ expresses a hope that the review of some of the characteristics of rivers given in one of the chapters of his _Rivers of North America_[B] may stimulate a desire in American students "to know more of the many and varied charms of their native land." The study of rivers is an alluring one, whether pursued upon the little local stream of one's neighborhood or upon the grand rivers that form systems and determine geographical districts; whether made with the assistance of a fishing-rod or of a steamboat. It can not fail to be promoted by Mr. Russell's instructive book, which the local student or the excursionist may consult with profit, while the geographer and geologist will find it a convenient manual. A river, when we come to think of it, means a great deal. Economically, it is the most valuable topographical feature a country can possess; geologically and geographically, it is a result of prominent features of the earth's structure, and is the cause of modifications in its surface which in time may revolutionize the topographical conditions and produce climatic and physical changes. All these characteristics of rivers are systematically and comprehensively set forth in Mr. Russell's book, where the life-history of the stream is presented, from its beginning in a little mountain torrent or hillside rill, through its course as it descends to the plain, wearing and tearing and deepening its channel. In the plain its character and action are modified under the new conditions in which it finds itself, and gradually, as it approaches its mouth, it deposits, whereas it had torn away at its beginning, and shows contrasts quite as marked as those between youth and old age. Rivers have their growth in time, too, and a stream that has been carrying on its work for long ages presents different characteristics throughout its course from one that comes fresh to its task, and these differences are pointed out. We are told, too, how rivers grow, drawing new affluents to themselves and extending their sources backward, and how when the sources of streams on different sides of a watershed approach on the summit, there is a struggle for the mastery. These are only a few of the new suggestions which the book offers us. Coming to the more matter-of-fact details, the laws governing streams and their course; the influence of inequalities and the hardness of rocks, especially on riverside scenery; and the office of rivers as carriers of material in suspension and in solution, are considered; then their deposits, under various heads and aspects, and the effects of changes in the elevation of the land, of variations in the load of material and of changes of climate upon them; the origin and characteristics of stream terraces and stream development, the topics concerning which are too many and varied to bear more than a passing reference. The more salient characteristics of American rivers are discussed as to the nine drainage slopes--the Atlantic, St.