reverse of the hypothesis of Ricardo, and by establishing the consequences which flow from it, restored harmony to what was before a mass of discordances, and rendered it possible, for the first time, to construct a science out of what was, at best, but a mere collection of empirical rules. In addition to the special acknowledgments made to that gentleman in the following pages, it is proper to say, that the author is so thoroughly sensible that he owes whatever his own study of the subject may have effected, to his having been put upon the path and furnished with the clue, in the writings of Mr. Carey, as to be quite indisposed to make pretensions on the score of originality, which, as against others, he might maintain. Upon this point, however, he is reasonably indifferent. The object of preparing this Manual was, to present to his countrymen in a compact form, the principles of what he thinks may justly be called the American System of Political Economy, not less on the ground of its origin, than its signal agreement with our social and political organization. It was desirable to exhibit what might be distinctive, in connection with the general doctrines in which Economists on both sides of the Atlantic agree, in such a manner as to give an outline of the science, adapted to popular reading or to elementary instruction. This imposed upon the writer all the brevity that is consistent with a clear demonstration of the leading principles. He trusts, however, that they have been sufficiently elucidated to afford important aid in the solution of many of the problems, the direct discussion of which he was compelled to forego, with much else that might have given interest to the work; and, that, while a teacher would find room for abundant illustration, any individual of mature years, who may read it without such aid, will meet with no more severe demand upon his reflective powers, than is incident to the treatment of so extensive a subject within such a compass, as to permit the hope of popular