Representation and Taxation.—­The Southern members of the convention were therefore very anxious to secure for their section the largest possible representation in Congress, and at the same time to restrain the taxing power of that body.  Two devices were thought adapted to these ends.  One was to count the slaves as people when apportioning representatives among the states according to their respective populations; the other was to provide that direct taxes should be apportioned among the states, in proportion not to their wealth but to the number of their free white inhabitants.  For obvious reasons the Northern delegates objected to these proposals.  Once more a compromise proved to be the solution.  It was agreed that not all the slaves but three-fifths of them should be counted for both purposes—­representation and direct taxation.

Commerce and the Slave Trade.—­Southern interests were also involved in the project to confer upon Congress the power to regulate interstate and foreign commerce.  To the manufacturing and trading states this was essential.  It would prevent interstate tariffs and trade jealousies; it would enable Congress to protect American manufactures and to break down, by appropriate retaliations, foreign discriminations against American commerce.  To the South the proposal was menacing because tariffs might interfere with the free exchange of the produce of plantations in European markets, and navigation acts might confine the carrying trade to American, that is Northern, ships.  The importation of slaves, moreover, it was feared might be heavily taxed or immediately prohibited altogether.

The result of this and related controversies was a debate on the merits of slavery.  Gouverneur Morris delivered his mind and heart on that subject, denouncing slavery as a nefarious institution and the curse of heaven on the states in which it prevailed.  Mason of Virginia, a slaveholder himself, was hardly less outspoken, saying:  “Slavery discourages arts and manufactures.  The poor despise labor when performed by slaves.  They prevent the migration of whites who really strengthen and enrich a country.”

The system, however, had its defenders.  Representatives from South Carolina argued that their entire economic life rested on slave labor and that the high death rate in the rice swamps made continuous importation necessary.  Ellsworth of Connecticut took the ground that the convention should not meddle with slavery.  “The morality or wisdom of slavery,” he said, “are considerations belonging to the states.  What enriches a part enriches the whole.”  To the future he turned an untroubled face:  “As population increases, poor laborers will be so plenty as to render slaves useless.  Slavery in time will not be a speck in our country.”  Virginia and North Carolina, already overstocked with slaves, favored prohibiting the traffic in them; but South Carolina was adamant.  She must have fresh supplies of slaves or she would not federate.