The Supreme Court is established by Article III, Section 1 of the Constitution of the United States, which says: "The judicial Power of the United States, shall be vested in one supreme Court .
The size of the Court is not specified; the Constitution leaves it to Congress to set the number of justices.
The dispute in McCulloch involved the legality of the national bank and a tax that the state of Maryland imposed on it.
122 (1819), dealt with the constitutionality of New York having passed bankruptcy laws and retroactively applying them.
The case arose when the president of Dartmouth College was deposed by its trustees, leading to the New Hampshire legislature attempting to force the college to become a public institution, and so place the ability to appoint trustees in the hands of the governor of New Hampshire.
The Supreme Court upheld the durability of the original charter of the college, which pre-dated the creation of the State.