thought for more than two hundred years, and bids fair to occupy once more the superior, if no longer the only, seat upon the throne. By combining it as a theory of natural price with Locke's supply-and-demand explanation of value as a theory of market price, it became possible to construct, as, perhaps, without conscious dependence upon Petty, or even upon Locke, Adam Smith did eventually construct, a theory of value so satisfactory that, when amended in some minor prints, John Stuart Mill could pronounce it "complete." Of course, it was not as complete as Mill thought it; but the contribution of its characteristic element is no mean achievement.
IV.
The second group of Petty's pamphlets, comprising the Political Anatomy of Ireland (1672) and the Political Arithmetick (1676), is predominantly descriptive. As might be expected from the specific circumstances which gave rise to the Political Anatomy of Ireland, its chief value springs from its author's unrivalled acquaintance with the condition of that island during the quarter-century after the Cromwellian settlement. Undeniably, the book has its blemishes. It contains some of the least admissible of Petty's calculations. It is not without numerical trivialities. But, on the whole, its merit is high. Economically, however, it merely repeats the suggestions of the earlier pamphlets, adding little or nothing new to Petty's known ideas. The Political Arithmetick deals chiefly with England. It, too, is in a sense descriptive. But detailed description is here consistently subordinated to a political purpose. The book is Petty's comment upon the rivalry between England and the continental nations for commercial control of the world. Of that great conflict it was his peculiar merit to take a large view. He
