Government, and of the mercantile community, to encourage its growth in new countries, it will be admitted that, as an _immediate_ and practical question, it is confined to those two sources. They are not only the sources from whence the largest supplies are received, but they are also those where the chief increase has taken place. "In 1840 the supply received from the United States was 487,856,000 lbs. Since that time, with some considerable fluctuations, it has steadily increased, until in 1858 it rose to 732,403,000 lbs.--the maximum quantity having reached in 1856, 780,040,000 lbs. Yet, great as this increase has been, it appears that it has not been equal to the increased demand, if we may judge from the price, at the two periods.[36] The large supplies of the last three years have commanded prices at least _sixteen per cent._ higher than the smaller supplies from 1840 to 1842. Every encouragement, therefore, which high and remunerative prices could give to increased cultivation has been liberally afforded to the cotton-growing States of America. "But whatever the price, there is a condition which places an absolute limit upon the growth. Land in every way suited for the purpose, is abundant and cheap. Means of transport is of the cheapest and best kind, and is without limit. The limit lies in the necessary ingredient of labor. If cotton had been the produce of free labor, no doubt the principle of supply and demand would have solved the difficulty. The surplus of the Old World would have steadily maintained the balance between the two in the New World. Ireland, Germany, Switzerland, the Southern parts of France, and Portugal, would have sent their surplus labor to the best market. As it is, the two kinds of labor--that of the freeman and that of the slave--can not be united in the same cultivation. The slave States of America are, therefore, dependent for any increase of labor only upon themselves. The consuming States can draw supplies only from the breeding States. It is, therefore, exactly in proportion as the slave population increases that the cotton crop becomes larger. Taking the average of three or four years at any period of the history of the United States for the last forty years, it will be found that the growth of cotton is equal to one bale for each person of the slave population. The calculation is well known. When the slave population was two millions, the average produce of cotton was two millions of bales:--as the one rose the other increased. The slave population is now about three millions and a half; the cotton crop of the present year is computed at from 3,500,000 to 3,700,000 bales. The high price of cotton, and the great profit attached to its cultivation, have no doubt furnished the greatest stimulant to an increase of that part of the population. In the competition for more labor, the price of slaves was enormously increased. Some years ago the price of a slave was