In those counties of South Carolina which lay wholly within the Piedmont the fifteen thousand slaves on hand in 1790 formed slightly less than one-fifth of the gross population there.

By 1800 the number of slaves increased by seventy per cent., and formed nearly one-fourth of the gross; in the following decade they increased by ninety per cent., until they comprised one-third of the whole; from 1810 to 1820 their number grew at the smaller rate of fifty per cent, and reached two-fifths of the whole; and by 1830, with a further increase of forty per cent., the number of slaves almost overtook that of the whites.

The slaves were then counted at 101,982, the whites at 115,318, and the free negroes at 2,115.

In Georgia the slave proportion grew more rapidly than this because it was much smaller at the outset; in North Carolina, on the other hand, the rise was less marked because cotton never throve there so greatly.
In its industrial requirements cotton was much closer to tobacco than to rice or sugar.

There was no vital need for large units of production.