"Fully to renovate the eight million acres of partially exhausted lands in the State of New York, will cost at least an average of twelve dollars and a half per acre, or an aggregate of one hundred millions of dollars. It is not an easy task to replace all the bone-earth, potash, sulphur, magnesia, and organized nitrogen in mould consumed in a field which has been unwisely cultivated fifty or seventy-five years. Phosphorus is not an abundant mineral anywhere, and his _sub-soil_ is about the only resource of the husbandman after his surface-soil has lost most of its phosphates. The three hundred thousand persons that cultivate these eight million acres of impoverished soils annually produce less by twenty-five dollars each than they would if the land had not been injured. "The aggregate of this loss to the State and the world is seven million five hundred thousand dollars per annum, or more than seven per cent. interest on what it would cost to renovate the deteriorated soils. There is no possible escape from this oppressive tax on labour of seven million five hundred thousand dollars, but to improve the land, or run off and leave it."--_Patent Office Report_, 1849 It is not slavery that produces exhaustion of the soil, but exhaustion of the soil that causes slavery to continue. The people of England rose from slavery to freedom as the land was improved and rendered productive, and as larger numbers of men were enabled to obtain subsistence from the same surface; and it was precisely as the land thus acquired value that they became free. Such, too, has been the case with every people that has been enabled to return to the land the manure yielded by its products, because of their having a market at home. On the contrary, there is no country in the world, in which men have been deprived, of the power to improve their land, in which slavery has not been maintained, to be aggravated in intensity as the land became more and more exhausted, as we see to have been the case in the West Indies. It is to this perpetual separation from each other that is due the poverty and weakness of the South. At the close of the Revolution, the now slave States contained probably 1,600,000 people, and those States contained about 120,000,000 of acres, giving an average of about eighty acres to each. In 1850, the population had grown to 8,500,000, scattered over more than 300,000,000 of acres, giving about forty acres to each. The consequence of this dispersion is that the productive power is very small, as is here seen in an estimate for 1850, taken from a Southern journal of high reputation:--[47]