_How the General Unification of Methods of Production Calls at First for an Increased Exportation of Capital from the Central Area and Checks the Immigration of Laborers._--A study of the causes of the interchanges which take place between the economic center and its environment shows that the movement of goods, the diffusion of modern methods of making goods, and the movements of capital and labor across the border of the economic society we are studying are interdependent. Opening a field for a profitable export trade increases the productivity of labor at home and tends to attract immigration. On the other hand, establishing in the outer zone a market for the products of the center prepares the way for introducing modern manufactures into the more densely peopled parts of the outer area. The company that sells cotton goods to the Chinese or the Hindoos will find that there is more to be made by utilizing the cheap labor of those peoples for making the goods by efficient machinery. Commerce tends to diffuse a knowledge of the most economical processes of manufacturing, and this interposes a certain stay on migrations of labor toward the center. It will in time help to retain Chinamen in China and Hindoos in India. It does, however, cause a movement of capital from the center outward, followed in time by a creation of wealth in the outer zone for proprietors residing within the center. The Englishman draws dividends from investments in many lands not within the field covered by the present studies. In so far as he reinvests them, as capital, in those lands, they supply a need that, without them, would have to be supplied by a new exportation of capital from the home country, and they therefore tend to check such exportation. In so far as the dividends are brought home they directly neutralize a certain amount of exportation of capital.