mountains and rivers, of redoubts, houses, and villages, covering a siege, infantry, cavalry, and artillery combats and reconnoissances, each involve special principles, and are treated separately.  In the course of the article on battles, some general observations are introduced on conducting manoeuvres so as to insure promptness, security, and precision.  The conduct of topographical reconnoissances is well explained by means of a map of a supposed district of country, with marked features, which is to be examined.  On this the course of the reconnoitring party, as it goes over the whole, is traced step by step, and fully explained in the letter-press.  In the concluding chapter the author treats of convoys, ambuscades, advance posts, the laying-out of camps, and giving rest to troops.

Such are the outlines of a subject which General Dufour has handled in a masterly manner.  His maxims are practical in their bearing, they commend themselves to our common sense as sound in principle, and are such as have received the indorsement of the best authorities.  His style is clear and comprehensive; nothing superfluous is inserted, nothing need be added to make the subject more clear.  The illustrations, which are given wherever they are needed, are simple and clear; the explanations are sufficient.  This work will be a valuable manual to soldiers, and students will find it an excellent text-book.  We hail it as an important addition to our growing military literature.

Man and Nature; or, Physical Geography as modified by Human Action.  By GEORGE P. MARSH.  New York:  Charles Scribner. 8vo. pp. 560.

The student of Physical Geography must not expect to find in this massive book a systematic exposition of the science in the manner of Guyot and the French and German geographers; nor must he expect to see worked out on its pages the elaborate application of Geography to History, such as one day will be done, and such as was attempted, though with results of varied value and certainty, by the eloquent and plausible Buckle; but he will find an unexpected development of man’s dominion over the world he inhabits.  Mr. Marsh takes his readers very much by surprise; for few are aware, we apprehend, that in the course of his wandering life, and while prosecuting his eminent philological studies, he has made leisure enough to survey the natural sciences with critical exactness, pursue an extended course of inquiry into physical phenomena, note and digest the results of Italian, Spanish, English, French, German, Dutch, and American naturalists, ply every guide and ploughman, every driver and forester, every fisherman and miner, every lumberman and carpenter, for the results which men attain by observing within the narrow circle of their occupation,—­and weave all into a copious work which subordinates all results to a grand psychological law, the mastery of man’s mind over the world it calls its home.