The purpose of this article is to examine a significant change that took place in American public policy during the nineteenth century. For many decades American governments, especially those of states and localities, had engaged in extensive programs for the promotion of economic development by the construction or support of works of internal improvement. It may now be pertinent, at a time when so many of the less industrialized countries are engaged in programs of economic development, to ask why and when and by what processes governments in the United States came to withdraw from direct participation in the promotion of canals and railways.

Concepts of the terms of trade as a means of measuring a country's gain or loss from exchange of goods have been discussed by students of economic theory for a hundred years or more. Until comparatively recently they have remained concepts only, without substantive application, but the tremendous disturbances in trading relationships and monetary standards in the last three decades have quickened interest in the subject. The various formulas devised for the measurement of relative movements of prices and quantities of exports and imports are now used with increasing frequency for the study of relatively current situations. They have not been applied much as yet to illuminate earlier trading history, largely because of the labor involved in deriving and organizing the limited data available. Apart from this difficulty there seems to be no very strong reason why they should not be as useful for economic history as for current analysis.

Two major themes have been developed by Ernest Labrousse in his well-known works on prices and income. One, a reinterpretation of the origins of the French Revolution, does not concern us here. The other, a theory of an agriculturally determined business cycle, has recently been confirmed for the early nineteenth century by a young historian and student of Labrousse, M. A. Chabert, and forms the subject of this paper. Chabert's first work offered time series of French prices from 1798 to 1820, a hitherto neglected interval falling between the monetary anarchy of the assignats and the period covered by the tables of the Bureau de la Statistique Générale. He has followed this with a more ambitious effort, a general study of the social and economic development of France during the same years, as reflected in the price series already presented and other data assembled since.

Any historian feels free to shift, enlarge, or contract his spatial or temporal field of attention, but the building of formal conceptions of time and space as flexible is something else. Fernand Braudel's recent book contains many revisions of judgment concerning the economic history of the centuries it treats, and also a way of handling space and time that gives the volume theoretical as well as historical interest. In his title, “the Mediterranean” refers to the region as well as to the sea. His “Mediterranean world” includes various outside areas, some remote, that have been related to the region by the activities of man in society. Peripheral mountains and deserts, for example, are considered in much detail, and four historic corridors (he calls them isthmuses) to northern waters are formally discussed. His “Epoch of Philip II” is in the first third of the book hardly a temporal “home port”; it is touched more frequently in Part II and is much used in the final section.