POWER TO DIVERT AN INTERSTATE RIVER. 147 Constitution of the United States." Matthews, J. 114 U. S. p. 292. By adopting the United States Constitution and joining the Union the State has parted with its "sovereign right of judg- ing in every case on the justice of its own pretensions." ^ The question of the validity of State action thenceforth " ceases to be a political one, to be decided by the sic volo, sic jubco, of political power ; it comes to the court to be decided by its judgment ; " the court being "bound to aT:t by known and settled principles of national or municipal jurisprudence, as the case requires." ^ To "insure domestic tranquillity " is one of the objects expressly enumerated in the preamble to the United States Constitution. The otherwise imminent danger of war between the States is one of the prominent reasons urged by Hamilton in the Federalist for adopting the Constitution.^ And great stress was laid by the same writer on the necessity of conferring jurisdiction upon the Fed- eral judiciary to settle disputes between States, and also disputes between citizens of different States. " If such disputes could not be brought before the Courts of the Union there would be no effectual means of settlement, and the difficulty might result in interstate war."* "Whatever practices may have a tendency to disturb the harmony of the States, are proper objects of Federal superintendence and control." ^ "The act," it will be said, "which gives rise to the injury is an act done in Massachusetts." True ; but its operation, its inevitable operation, is not confined to the limits of that State. If the plea that the act was done in Massachusetts is allowed as a perfect defence, it can also be used to justify damming in Massachusetts (close to the State line) a river flowing from New Plampshire to Massachusetts, and thus flooding New Hampshire territory by back water. In this way, by damming the Merrimack, Massachu- setts might destroy the border city of Nashua, perhaps not more certainly, but more speedily, than by the present attempt to divert the source of its water power. So, if this plea be valid, Massachu- setts can undermine the entire strip of Massachusetts land adjoin- ing the New Hampshire boundary, and can explode the mine without any liability on the part of its agents for the inevitable result of upheaving the soil and demolishing the buildings on the New Hampshire side of the line. In the well-known case of City 1 See 6 Wheaton, p. 380. * 2 Hare, Const'l Law, p. 1024.
- Compare Baldwin, J., 12 Peters, p. 737. ^ Federalist, Number 80.
8 Federalist, Numbers 6 and 7.
