But Massachusetts did not become a manufacturing State until after the tariff of 1824. That measure, as well as the whole protective policy, Massachusetts earnestly opposed in 1820 and 1824, and Daniel Webster, as her representative, denounced it as unconstitutional. From 1790 to 1820 Massachusetts was commercial, not manufacturing, and yet, from 1790 to 1820, Massachusetts increased in numbers 144,442, and Maryland in the same time only 87,622. Yet, from 1790 to 1820, Massachusetts, the most commercial State, was far more injured by the embargo and the late war with England than any other State. It is clear, then, that the accusation of the secession leaders that the North was built up at the expense of the South, by the tariff, can have no application to the progress of Massachusetts and Maryland, because the advance of the former over the latter preceded by more than thirty years the adoption of the protective policy, and a comparison of the relative advance of the free and slave States, during the same period, exhibits the same results. There is one _invariable law_, whether we compare all the slave States with all the free States, small States with small, large with large, old with old, new with new, retarding the progress of the slaveholding States, ever operating, and differing in degree only. The area of the nine free States enumerated in 1790, is 169,668 square miles, and of the eight slaveholding States 300,580 square miles, while the population of the former in 1790 was 1,968,455, and of the latter, 1,961,372; but, in 1860, these nine free States had a population of 10,594,168, and those eight slave States only 7,414,684, making the difference in favor of these free States in 1860 over those slave States, 3,179,844, instead of 7,083 in 1790, or a positive gain to those free States over those slave States of 3,172,761. These free States, enumerated in 1790 and 1860, were the six New England States--New York, New Jersey, and Pennsylvania; and the slave States were, Delaware, Maryland, Virginia, North and South Carolina, Georgia, Tennessee, and Kentucky--yet we have seen that the area of those slave States was nearly double that of those free States, the soil much more fertile, the climate more salubrious, as shown by the census, and the shore line, including main shore, bays, and sounds, islands and rivers, to head of tide water, was, for those free States, 4,480 miles, and for those slave States, 6,560 miles. Thus, it is clear, that the increase of population of these slave States should have far exceeded that of those free States. The population of these slave States per square mile in 1790 was six (6.52), and in 1860, 24 (24.66), and of those free States in 1790, was 11 per square mile (11.60), and in 1860, 62 per square mile (62.44). Thus, while the increase of those slave States from 1790 to 1860 was only 18 per square mile, that of those free States was nearly 51 per