144 HARVARD LAW REVIEW. The United States government treats the diversion or obstruction of the ordinary flow of water, when caused by foreign nations, as a national grievance, affording ground for national complaint. In 1880, Secretary Evarts wrote to the United States min- ister at the Mexican capital, and also to the Mexican minister at Washington, complaining that the Mexicans on the western shore of the Rio Grande are in the habit of diverting, into ditches dug for that purpose, all the water that comes down the river in the dry season, thereby preventing our citizens on the Texan shore from getting sufficient water to irrigate their crops. He said that this practice is " in direct opposition to the recognized rights of riparian owners, " and that it " might eventually, if not amicably adjusted through the medium of diplomatic intervention, be pro- ductive of constant strife and breaches of the peace between the inhabitants of either shore. " In 1884, Secretary Frelinghuysen wrote to the United States minister at the British Court, that the erection of works on the Meduxnikik River in New Brunswick, in such a way as to obstruct the flow of water in Maine, and to injure the lumbering business in that State, is a proper subject for diplo- matic interposition by this government, ^ Where a river flows successively through two sovereign States, there has been much dispute as to the right of one of the States to exclude the people of the other State from navigating that part of the river which flows through the territory of the former State. Thus if Massachusetts and New Hampshire were each indepen- dent nations, and the Nashua River were a navigable stream, it would be a question whether Massachusetts could deny to the people of New Hampshire the right to navigate the waters of the Nashua River while and so long as those waters flow between Massachusetts banks. Our national government has objected strenuously against the right to exclude. Thus it denied the right of Spain to exclude our citizens from the navigation of the lower part of the Mississippi River before the Louisiana cession of 1803 ; and has also questioned the right of Great Britain to exclude the United States from the St. Lawrence. One high authority on international law sustains the position of our government. The weight of modern authority seems against it ; though it should be noted that one of the leading English writers upon international law, while inclining to the view that the exclusion may be grounded ^ I Wharton's International Law Digest, § 20.
