The further achievements of that generation in this matter were considerable.  It must of course be understood that the holding of slaves and the slave trade from Africa were regarded as two distinct questions.  The new Congress abolished the slave trade on the first day on which the Constitution allowed it to do so, that is, on January 1, 1808.  The mother country abolished it just about the same time.  But already all but three of the States had for themselves abolished the slave trade in their own borders.  As to slavery itself, seven of the original thirteen States and Vermont, the first of the added States, had abolished that before 1805.  These indeed were Northern States, where slavery was not of importance, but in Virginia there was, or had been till lately, a growing opinion that slavery was not economical, and, with the ignorance common in one part of a country of the true conditions in another part, it was natural to look upon emancipation as a policy which would spread of itself.  At any rate it is certain fact that the chief among the men who had made the Constitution had at that time so regarded it, and continued to do so.  Under this belief and in the presence of many pressing subjects of interest the early movement for emancipation in America died down with its work half finished.

But before this happy belief expired an economic event had happened which riveted slavery upon the South.  In 1793 Eli Whitney, a Yale student upon a holiday in the South, invented the first machine for cleaning cotton of its seeds.  The export of cotton jumped from 192,000 lbs. in 1791 to 6,000,000 lbs. in 1795.  Slave labour had been found, or was believed, to be especially economical in cotton growing.  Slavery therefore rapidly became the mainstay of wealth and of the social system in South Carolina and throughout the far South; and in a little while the baser sort of planters in Virginia discovered that breeding slaves to sell down South was a very profitable form of stock-raising.

We may pass to the year 1820, when an enactment was passed by Congress which for thirty-four years thereafter might be regarded as hardly less fundamental than the Constitution itself.  Up till then nine new States had been added to the original thirteen.  It was repugnant to principles still strong in the North that these States should be admitted to the Union with State Constitutions which permitted slavery.  On the other hand, it was for two reasons important to the chief slave States, that they should be.  They would otherwise be closed to Southern planters who wished to migrate to unexhausted soil carrying with them the methods of industry and the ways of life which they understood.  Furthermore, the North was bound to have before long a great preponderance of population, and if this were not neutralised by keeping the number of States on one side and the other equal there would be a future political danger to slavery.  Up to a certain point the North could