Another principal division of Mr. Lesley's book treats of the ores of iron in the United States. This portion of the book contains much valuable and interesting information, which has never been published before in so complete and satisfactory a form. The geographical and geological position of every ore-bank in the country, which has been opened and worked, is fully described, with many details of the peculiar properties, mineralogical associations, and history of each bed or mine. The inexhaustible wealth of the country in ores of iron is clearly shown, and the superiority of the American ores to the English needs no other demonstration than can be found on the pages of this catalogue of our ore-beds. Two or three geological maps, to illustrate the distribution of the ores, would have been an instructive addition to the book. In this section, as in the preceding one on the chemistry of iron, much space is misapplied to the discussion of questions of structural geology, of opposing theories of the formation of veins, and other scientific problems with which the iron-master is not concerned, and which he cannot be expected to understand, much less to solve. We regret the more this unnecessary introduction of comparatively irrelevant matters, when we find, at the close of the volume, that the unexpected length of the discussion of the ores has prevented the publication of several chapters on the machinery now in use, the hot-blast and anthracite coal, the efforts to obtain malleable iron directly from the ore, and the history and present condition of the iron-manufacture in America. The American Iron-Association, by their Secretary, have accomplished a very laborious and valuable work, in accumulating and digesting the mass of facts and statistics embodied in this, the first "Iron-Manufacturer's Guide"; but the subject is as inexhaustible as the mineral wealth of the country, and we shall look for the future publications of the society with much interest. _An Essay on Intuitive Morals_. Being an Attempt to Popularize Ethical Science. Part I. Theory of Morals. First American Edition, with Additions and Corrections by the Author. Boston: Crosby, Nichols, & Co. 1859. pp. 294.