The legislation of 1815 and 1816 showed to the Court that its view of the Constitution was accepted by the people; and it now began a series of great constitutional decisions, which put on record as legal precedents the doctrines of implied powers and of national sovereignty. In the great cases of Martin _vs._ Hunter's Lessee, and Cohens _vs._ Virginia, in 1816 and 1821, it asserted the right of the Supreme Court to take cases on appeal from the State courts, and thus to make itself the final tribunal in constitutional questions. At about the same time, in two famous cases, McCullough _vs._ Maryland in 1819, and Osborn et al. _vs._ Bank of the United States in 1824, the doctrine of implied powers was stated in the most definite manner. Both cases arose out of the attempt of States to tax the United States Bank, and the final issue was the power of Congress to charter such a bank. The doctrine laid down by Hamilton in 1791 (§ 78) was reaffirmed in most positive terms. "A national bank," said Marshall, "is an appropriate means to carry out some of the implied powers, a usual and convenient agent.... Let the end be within the scope of the Constitution, and all means which are ... plainly adapted to that end, which are not prohibited,... but consistent with the letter and spirit of the Constitution, are constitutional." Although the tariff act was not tested by a specific case, the spirit of the decision reached it also. [Sidenote: State powers limited.] [Sidenote: Impairment of contracts.] Having thus asserted the authority of the nation on one side, the Court proceeded to draw the boundary of the powers of the States on the other side. In a question arising out of grants of land by the Georgia legislature in the Yazoo district, it had been claimed that any such grant could be withdrawn by a subsequent legislature. The Court held in Fletcher _vs._ Peck, in 1810, that such a withdrawal was in contravention of the constitutional clause which forbade the States to impair the obligation of contracts. In 1819, in the celebrated case of Dartmouth College _vs._ Woodward, this principle was pushed to an unexpected conclusion. The legislature of New Hampshire had passed an act modifying a charter granted in colonial times to Dartmouth College. Webster, as counsel for the Board of Trustees which had thus been dispossessed, pleaded that a charter granted to a corporation was a contract which could not be altered without its consent. Much indirect argument was brought to bear upon Marshall, and eventually the Court held that private charters were contracts. The effect of this decision was to diminish the power and prestige of the State governments; but the general sentiment of the country sustained it. So united did all factions now seem in one theory of national existence that in the election of 1820 Monroe received every vote but one. 126. THE SLAVERY QUESTION REVIVED (1815-1820). [Sidenote: Silent growth of slavery.]