Archeologists assure us that organized social life has existed on this earth for about two hundred and fifty thousand years. How millions of people have sought to satisfy their wants over this tremendous span of time is the acknowledged province of economic history. Yet, for lack of records, the gild of economic historians must, for the most part, confine their attention to the last one per cent of this time span; indeed the great bulk of research in economic history is devoted the last one-tenth of one per cent of the archeologists' two hundred and fifty thousand years of social history. Even then the economic historian is utterly overwhelmed with facts. He who essays to write the economic history of the United States, for example, must depict as best can the economic activities of people for more than a hundred and fifty years, farmers, merchants, manufacturers, wage-earners, rentiers; men, women and children in all walks of life, in all variety of occupations. The task is utterly staggering. An army of economic historians would be required to write a complete economic history of the United States; a regiment at least to write a faithful factual account of a single industry.