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this little volume Dr. Alden has furnished us with an invaluable common-school manual, which can not too soon or too generally be put into the hands of American youth. It is the best introduction to political economy for beginners in primary schools that we have seen, and its universal adoption as a part of the course of elementary study could not fail to result in ultimate widespread benefit. The aim of the author has been "to present simple elementary truths connected with the business activities of life," and this he has done with excellent judgment as respects the subjects chosen and with remarkable clearness and simplicity of statement. There has been a good deal of caviling recently as to whether there is or is not such a science as political economy. No doubt, the excess of modern controversial literature over unsettled questions in political economy has favored this skeptical state of mind; but any one who will look over a little summary of elementary principles like this of Dr. Alden's must be satisfied that there is a broad basis of established truth on which a strict economical science can securely rest.

opportunity afforded by a four years' sea-saunter in a ship, and with a party dedicated to scientific exploration, was well improved by Mr. Moseley, as is evinced by this goodly volume. Not by any means that the book embodies the scientific results of his extended observations, which when finally worked up will appear in other shapes, but it presents a great deal of interesting scientific and semi-scientific matter in connection with a readable and varied narrative of the experiences of the expedition. It is an especially well-executed book of travels, by an intelligent and thoroughly-trained observer, laboring in circumstances especially favorable for collecting interesting information. The main portion of it was prepared for family reading, written on board the Challenger, and sent home in the form of a journal from the various ports touched at. The materials have been carefully revised, but they take the character of a narrative describing the scenes, the aspects of nature, the curiosities and novelties of animal and vegetable life, and the characters, habits, and social conditions of the different kinds of people encountered along the route. The volume is written in a pleasant, unambitious style, but often with humorous touches and lively descriptions, which increase the attractiveness of its contents. The following passages express some of the impressions of the author, after his return, and are given at the close of his book:

After a voyage all over the world, there is nothing which is so much impressed upon the mind as the smallness of the earth's surface. We are apt to regard certain animals as fixed and stationary, and to contrast strongly with their condition that of forms possessing powers of active locomotion. In reality we are as securely fixed by the force of gravity as is the sea anemone by its base; we can only revolve as it were at the end of our stalk, which we can lengthen or shorten only for a few miles' distance. We live in the depths of the atmosphere as deep-sea animals live in the depths of the sea. We can, like these, crawl up into the shallows, or we can occasionally mount at peril in a balloon; but the utmost extent of our vertical range is a distance no greater than that which we can walk in a couple of hours horizontally on the earth's surface.

The Challenger traveled, on the voyage from Portsmouth and back to the same port, 68,690 miles, and this distance, taking into consideration the time consumed from port to port, was traversed at the average pace of only four miles an hour, or fast walking pace. In an express train on land the entire distance could be conceived of as being accomplished in eight weeks, and, at the rate at which a swallow can fly, in about half that time.

The earth, considered as a comparatively insignificant component particle of the universe, may be justly compared to a small isolated island on its own surface. As, in the course of ages, such an island develops its own peculiar insular fauna and flora, so probably on the surface of the earth alone has the peculiarly complex development of the element nitrogen occurred which has resulted in the various forms of animal and vegetable life.

On the theory of evolution, it is impossible that plants or animals of any advanced