This uncertainty has not been removed by the practical working of our institutions in later times; for although the acquisition of additional territory and the application of steam to the propulsion of vessels have greatly magnified the importance of internal commerce, this fact has at the same time complicated the question of the power of the General Government over the present subject.

In fine, a careful review of the opinions of all my predecessors and of the legislative history of the country does not indicate any fixed rule by which to decide what, of the infinite variety of possible river and harbor improvements, are within the scope of the power delegated by the Constitution; and the question still remains unsettled.  President Jackson conceded the constitutionality, under suitable circumstances, of the improvement of rivers and harbors through the agency of Congress, and President Polk admitted the propriety of the establishment and support by appropriations from the Treasury of light-houses, beacons, buoys, and other improvements within the bays, inlets, and harbors of the ocean and lake coasts immediately connected with foreign commerce.

But if the distinction thus made rests upon the differences between foreign and domestic commerce it can not be restricted thereby to the bays, inlets, and harbors of the oceans and lakes, because foreign commerce has already penetrated thousands of miles into the interior of the continent by means of our great rivers, and will continue so to extend itself with the progress of settlement until it reaches the limit of navigability.

At the time of the adoption of the Constitution the vast Valley of the Mississippi, now teeming with population and supplying almost boundless resources, was literally an unexplored wilderness.  Our advancement has outstripped even the most sanguine anticipations of the fathers of the Republic, and it illustrates the fact that no rule is admissible which undertakes to discriminate, so far as regards river and harbor improvements, between the Atlantic or Pacific coasts and the great lakes and rivers of the interior regions of North America.  Indeed, it is quite erroneous to suppose that any such discrimination has ever existed in the practice of the Government.  To the contrary of which is the significant fact, before stated, that when, after abstaining from all such appropriations for more than thirty years, Congress entered upon the policy of improving the navigation of rivers and harbors, it commenced with the rivers Mississippi and Ohio.

The Congress of the Union, adopting in this respect one of the ideas of that of the Confederation, has taken heed to declare from time to time, as occasion required, either in acts for disposing of the public lands in the Territories or in acts for admitting new States, that all navigable rivers within the same “shall be deemed to be and remain public highways.”