Professor F. Y. Edgeworth, of Oxford University, delivered the first of his series of lectures yesterday evening, on the special subject of "The Theory of Value as Applied to International Trade." The pure theory of value investigated by Cournot and his followers, he said, may be applied to some of the principal propositions and problems in economics. It is particularly applicable to international transactions. The theory of exchange traced by Jevons facilitates the comprehension of "comparative cost" and other complications in the doctrine of international values. The difficulty of comparing quantities of labor or productive power is lessened by Mangoldt's conception of a commodity produced both by the home and the foreign country. New views serve to confirm the old arguments in favor of free trade. Abstract theory admits indeed the possibility that a country may benefit itself economically by a manipulation of tariffs; but the methods indicated are so refined and involved as to strengthen the general presumption of leaving trade relations unimpered with when there is no reasoned expectation that they will be bettered by regulation.