veloped exhaustively, together with their many corollaries and sequences, in the magistral work by which Marx is now better known than by any of his previous writings. It will be observed, however, that each of these two essays has its particular merits, and that both may be perused with benefit, even by the advanced student of Capital. For instance in Value, Price, and Profit, which was written in 1865—or only four years before Capital appeared in print—the subject more specially considered is the " law of value," which Marx had by that time worked out to the utmost limit of perfection; whereas in Wage-Labor and Capital, which was written in the early part of 1849, the general propositions are rather formulated than demonstrated, but are in greater number and variety, thus showing already the powerful framework of a vast structure, fully planned out, but requiring twenty years of patient labor for its completion.
Of the discourse on Free Trade, which forms the second part of the present volume, the history is given by Engels in the " Introduction" that precedes it. The excellent translation of it that is presented here was first published some years ago by Lee and Shepard, of Boston. It is the work of Florence Kelley, who not only authorized us to use it, together with the introduction that Engels had written at her own request, but, most kindly also, revised our proofs.
