The extraordinary resources of the United States are scarcely understood even by Americans. Chart No. XVIII (see Book IV, Chap. III) may give some idea of the agricultural possibilities of our land. It will be seen from this that the quantity of fertile land in but one of our States—Texas—is greater than that of Austria-Hungary. But the countries which have at the same time cheap food and great industrial prosperity are few, being only those in which the arts of civilized life have been transferred full-grown to a rich and uncultivated soil. Among old countries, those which are able to export food, are able only because their industry is in a very backward state, because capital, and hence population, have never increased sufficiently to make food rise to a higher price. Such countries are Russia, Poland, and Hungary. The law, therefore, of diminishing return to industry, whenever population makes a more rapid progress than improvement, is not solely applicable to countries which are fed from their own soil, but in substance applies quite as much to those which are willing to draw their food from any accessible quarter that can afford it cheapest. § 4. —Nor by Emigration. Besides the importation of corn, there is another resource which can be invoked by a nation whose increasing numbers press hard, not against their capital, but against the productive capacity of their land: I mean Emigration, especially in the form of Colonization. Of this remedy the efficacy as far as it goes is real, since it consists in seeking elsewhere those unoccupied tracts of fertile land which, if they existed at home, would enable the demand of an increasing population to be met without any falling off in the productiveness of labor. Accordingly, when the region to be colonized is near at hand, and the habits and tastes of the people sufficiently migratory, this remedy is completely effectual. The migration from the older parts of the American Confederation to the new Territories, which is to all intents and purposes colonization, is what enables population to go on unchecked throughout the Union without having yet diminished the return to industry, or increased the difficulty of earning a subsistence. How strictly true this is may be seen by examining the map given in the last census returns,(142) showing the residence of the natives of the State of New York. The greater or less frequency of natives of New York, residing in other States, is shown by different degrees of shading on the map. A large district westward as far as the Mississippi shows a density of natives of New York of from two to six to a square mile, and a lesser density from Minnesota to Indian Territory, on the other side of the Mississippi. The same is shown of other older States. The explanation of the movement can not be anything else than the same as that for the larger movement from Europe to America.