p.
300, pp.

370 et seq.; Story's "Commentaries," p.

646; and "The Organic Law of the United States," vol.i.p.

35.] This was a severe blow upon the independence of the States, which was thus restricted not only by the laws, but by the interpretation of them; by one limit which was known, and by another which was dubious; by a rule which was certain, and a rule which was arbitrary.

It is true the Constitution had laid down the precise limits of the Federal supremacy, but whenever this supremacy is contested by one of the States, a Federal tribunal decides the question.