Many people then believed that slavery would by degrees die out of the land, and perhaps this would have happened if the growing of cotton had not been made profitable by Eli Whitney's invention of the cotton-gin. After that invention came into use, instead of slavery's dying out, it took a much stronger hold upon the planters of the South than it had ever done before. This fact became very evident when Missouri applied for admission into the Union. The South, of course, wished it to come into the Union as a slave State; the North, fearing the extension of slavery into the Louisiana Purchase, was equally set upon its coming in as a free State. The struggle over the question was a long and bitter one, but finally both the North and the South agreed to give up a part of what they wanted; that is, they agreed upon a compromise. It was this: Missouri was to enter the Union as a slave State, but slavery was not to be allowed in any part of the Louisiana Purchase which lay north or west of Missouri. This was called the Missouri Compromise (1820). It was brought about largely through the eloquence and power of Henry Clay, and because of his part in it he was called "the Great Peacemaker." But Calhoun was one of the men who did not think the Missouri Compromise was a good thing for the country. He therefore strongly opposed it. The next clash between the free States and the slave States was caused by the question of the tariff, or tax upon goods brought from foreign countries. Not long after the Missouri Compromise was agreed upon, Northern manufacturers were urging Congress to pass a high-tariff law. They said that, inasmuch as factory labor in England was so much cheaper than in this country, goods made in England could be sold for less money here than our own factory-made goods, unless a law was passed requiring a tax, or duty, to be paid upon the goods brought over. Such a tax was called a protective tariff. Calhoun, who voiced the feeling of the Southern planters, said: "This high tariff is unfair, for, while it protects the Northern man, it makes us of the South poorer, because we have to pay so high for the things we do not make." You understand, there were no factories in the South, for the people were mostly planters. With the cheap slave labor, a Southern man could make more money by raising rice, cotton, sugar, or tobacco than he could by manufacturing. Also, it was thought that the soil and climate of the South made that section better fitted for agriculture than for anything else. "So the South should be allowed," said Calhoun, "to buy the manufactured goods--such as cheap clothing for her slaves, and household tools and farming implements--where she can buy them at the lowest prices." [Illustration: The Home of Daniel Webster, Marshfield, Mass.] But in spite of this bitter opposition in the South, Congress passed the high-tariff law in 1828, and another in 1832.