Carolinians ventured to defend slavery on principle. This belief in the moribund condition of slavery prevented the convention from realizing the actual effect of the concessions which were made. Scarcely any cotton was grown at that time, and none was sent to England. The industrial revolution about to be wrought by the inventions of Arkwright and Hargreaves, Cartwright and Watt and Whitney, could not be foreseen. Nor could it be foreseen that presently, when there should thus arise a great demand for slaves from Virginia as a breeding-ground, the abolitionist party in that state would disappear, leaving her to join in the odious struggle for introducing slavery into the national domain. Though these things were so soon to happen, the wisest man in 1787 could not foresee them. The convention hoped that twenty years would see not only the end of the foreign slave-trade, but the restriction and diminution of slavery itself. It was in such a mood that they completed the compromise by recommending a tariff of ten dollars a head upon all negroes imported, while at the same time a clause was added for insuring the recovery of fugitive slaves, quite similar to the clause in the ordinance for the government of the northwestern territory. [Sidenote: The foundations of the Constitution were thus laid in compromise.] It was the three great compromises here described that laid the foundations of our Federal Constitution. The first compromise, by conceding equal representation to the states in the Senate, enlisted the small states in favour of the new scheme, and by establishing a national system of representation in the lower house, prepared the way for a government that could endure. This was Madison's great victory, secured by the aid of Sherman and Ellsworth, without which nothing could have been effected. The second compromise, at the cost of giving disproportionate weight to the slave states, gained their support for the more perfect union that was about to be formed. The third compromise, at the cost of postponing for twenty years the abolition of the foreign slave-trade, secured absolute free-trade between the states, with the surrender of all control over commerce into the hands of the federal government. After these steps had been taken, the most difficult and dangerous part of the road had been travelled; the remainder, though extremely important, was accomplished far more easily. It was mainly the task of building on the foundations already laid. [Sidenote: Powers granted to the federal government.]