But the increase of the slave population of the South is obscured by no such disturbing cause. The South having magnanimously concurred, and even gone before, in suppressing the foreign slave trade, from a conviction of its immorality, the African race has received no accession whatever, in our day, from immigration. Between 1840 and 1850, the increase of the slave population solely from the excess of births over deaths, was twenty-eight and eight-tenths _per cent._, (28.8,) and between 1850 and 1860, it was twenty-three and three-tenths (23.3) _per cent._ One cause for the diminished rate of increase in the latter decade, was doubtless the growing passion of the Yankees for the abduction of our slaves; which, towards the last, carried off thousands annually. But either rate of increase is more rapid than the whites, either North or South, ever attained without the aid of immigration. The _native increase_ of the free States in ten years has probably been between eleven and fifteen _per cent._ So that tried by this well-established test, the physical well-being of the slaves is higher than of any race in the world. Meantime, the miserable free blacks of New England, in the midst of the boasted philanthropy of abolitionism, only increase at the rate of _one and seven-tenths_ of one _per cent._ in ten years! Such is the stern and impartial testimony of fact. How calamitous must be that load of social oppression, of disease and destitution, which thus nearly annihilates the increase of this fruitful race! Yet this is the condition to which the benevolent abolitionist would reduce the prosperous servants of the South.