142 * INTERNATIONAL TRADE Fo to the point of unreality (as, for example, that of taxes in kind). More commonly, the deduced conclusions, even if resting on prob- able assumptions, are such as cannot be specifically discerned or verified in the actual course of events. And, as I need hardly confess again, the mathematical processes by which alone some of these conclusions can be deduced are beyond my competence; [ could make no pretense of contributing anything new either in substance or in the way of exposition. Neither is it within the scope of the present volume to enter on the controversy regarding free trade and protection. This in its main outlines is simple; simple at all events as compared with the topics taken up in the preceding pages. In a later chapter I have summarized those results of my inquiries on the effects of tariff legislation which have some direct bearing on the principles with which the present volume deals. There is, however, one possible effect of taxes, and one phase of the protective controversy, on which something may here be said. I direct attention to this particular point of theory because of its connection with certain concrete problems of verification or interpretation which arise in connection with the international trade of the United States. The point is not of an essentially new or intricate kind. It relates to the effects which taxes on imports, and especially taxes which are protective, may have on the barter terms of trade. Suppose, first, that a country imposes duties on imports which are purely of a revenue character. The proximate effect is to raise within the country the price of the dutiable article or articles (hereafter we may speak for simplicity of but a single article). True, in the case of a commodity produced under monopoly condi- tions, and having an extraordinarily elastic demand schedule, the price might remain unaffected. But this is a negligible case ; under almost every imaginable condition there will be some rise in price. Assuming then, as we may, that price rises, less of the commodity will be bought. Only if demand were absolutely inelastic would the quantity bought remain the same. Demand being always in some degree elastic, less will be bought, and imports will decline.