During the latter part of the nineteenth century and the beginning of this century both international trade and national economies grew exponentially, with international trade growing considerably faster than national income. Contributors to these two volumes question whether trade's more rapid growth was an engine pulling successful economies, or whether government policies of trade protection had a greater impact upon national economic growth. The essays in this collection analyse four major driving forces of the period's sustained economic growth: changes in tariff policies; the technological 'revolution' in transportation costs; the population and income growth effects upon demand; and the alterations to comparative advantage brought about by technological changes and resource discoveries.