We have seen that, exclusive of commerce, the products of Pennsylvania in 1860 were of the value of $399,600,000, or $138 _per capita_; and in Virginia, $120,000,000, or $75 _per capita_. But, if we add the earnings of commerce, the products of Pennsylvania must have exceeded those of Virginia much more than four to one, and have reached, _per capita_, nearly three to one. What but slavery could have produced such amazing results? Indeed, when we see the same effects in _all_ the Free States as compared with _all_ the Slave States, and in _any_ of the Slave States, as compared with _any_ of the Free States, the uniformity of results establishes the law beyond all controversy, that slavery retards immensely the progress of wealth and population. That the Tariff has produced none of these results, is shown by the fact that the agriculture and commerce of Pennsylvania vastly exceed those of Virginia, and yet these are the interests supposed to be most injuriously affected by high tariffs. But there is still more conclusive proof. The year 1824 was the commencement of the era of high tariffs, and yet, from 1790 to 1820, as proved by the Census, the percentage of increase of Pennsylvania over Virginia was greater than from 1820 to 1860. Thus, by Table 1 of the Census, p. 124, the increase of population in Virginia was as follows: From 1790 to 1800 17.63 per cent. " 1800 " 1810 10.73 " " 1810 " 1820 9.31 " " 1820 " 1830 13.71 " " 1830 " 1840 2.34 " " 1840 " 1850 14.60 " " 1850 " 1860 12.29 " The increase of population in Pennsylvania was: From 1790 to 1800 38.67 per cent. " 1800 " 1810 34.49 " " 1810 " 1820 29.55 " " 1820 " 1830 28.47 " " 1830 " 1840 27.87 " " 1840 " 1850 34.09 " " 1850 " 1860 25.71 " In 1790 the population of Virginia was 748,318; in 1820, 1,065,129, and in 1860, 1,596,318. In 1790 the population of Pennsylvania was 434,373; in 1820, 1,348,233, and in 1860, 2,906,115. Thus, from 1790 to 1820, before the inauguration of the protective policy, the relative increase of the population of Pennsylvania, as compared with Virginia, was very far greater than from 1820 to 1860. It is quite clear, then, that the tariff had no influence in depressing the progress of Virginia as compared with Pennsylvania. Having shown how much the material progress of Virginia has been retarded by slavery, let us now consider its effect upon her moral and intellectual development.