price of slaves in those districts cannot fail to keep up. In many cases the planter of the Northern slave States emigrates to a region where he can employ his capital of thews and sinews more profitably than at home. In many others, he turns his plantation into an establishment for slave breeding, and sells his rising stock for labour in the cottonfield."--_Prospective Review_ Nov. 1852. Unhappily, however, for this reasoning precisely the same exhaustion is visible in the Northern States, as the reader may see by a perusal of the statements on this subject given by Professor Johnson, in his "Notes on North America," of which the following is a specimen:-- "Exhaustion has diminished the produce of the land, formerly the great staple of the country. When the wheat fell off, barley, which at first yielded fifty or sixty bushels, was raised year after year, till the land fell away from this, and became full of weeds."--Vol. i. 259. Rotation of crops cannot take place at a distance from market The exhaustive character of the system is well shown in the following extract:-- "In the State of New York there are some twelve million acres of improved land, which includes all meadows and enclosed pastures. This area employs about five hundred thousand labourers, being an average of twenty-four acres to the hand. At this ratio, the number of acres of improved land in the United States is one hundred, and twenty millions. But New York is an old and more densely populated State than an average in the Union; and probably twenty-five acres per head is a juster estimate for the whole country. At this rate, the aggregate is one hundred and twenty-five millions. Of these improved lands, it is confidently believed that at least four-fifths are now suffering deterioration in a greater or less degree. "The fertility of some, particularly in the planting States, is passing rapidly away; in others, the progress of exhaustion is so slow as hardly to be observed by the cultivators themselves. To keep within the truth, the annual income from the soil may be said to be diminished ten cents an acre on one hundred million acres, or four-fifths of the whole.