there is yet another branch of the subject.  A country whose population is beyond its means of supply from its own soil, has no resources but that of her manufactures and foreign trade; if these be dried up, her people must emigrate or starve.  But the United States has an alternative;—­her first and best resource,—­and the most profitable application of her industry is in her broad and fertile lands, the superabundant produce of which would not only feed, but, by exchange, clothe her population, and supply them with all the comforts of civilized life.  She cannot avail herself of this to its full extent without our aid.  But, if we refuse to trade on equal terms, her wants will not, therefore, go unsupplied.  She can manufacture for herself—­her resources for manufactures and commerce are, at least, equal to our own, with the exception of capital and population, which the lapse of a few more years will supply.

“The present may justly be considered a crisis in the commercial policy of America.  If it be decided that foreign markets are to continue closed against American corn—­if England, which is the principal corn market of the world, refuse to exchange the produce of her mills and workshops for that of the fields of the Americans, they have no other alternative than to erect mills and workshops from which to supply themselves.  The effect of such a course would prove decisive on the trade with England, and go far to complete the ruin so effectually begun by the British corn law and corresponding restrictions.  If forced from employment on the land, which an abundant and fertile soil has naturally made their most profitable one, it will be found that the Americans lack neither the talent, the energy, nor the means, at once to extend their present manufactures to the full supply of their own wants.  They have water-power, coal, and iron, in greater natural abundance and perfection than any other part of the world."[A]

[Footnote A:  “The United States are computed to contain not less than eighty thousand square miles of coal, or sixteen times as much as Europe.  One of these coal fields extends nine hundred miles in length.  The State of Pennsylvania has ten thousand square miles of coal and iron.  Great Britain and Ireland have two thousand.  All the north-western States of America contain large quantities of coal.  The coal strata of the States generally lie above the level of the streams, and the coal is taken from the hill sides.  The beds of coal and iron are to a great extent contiguous.”]

This is not mere theory.  The developement is actually begun: