At a later period it is true that, in disregard of the more comprehensive definition of navigability afforded by that act of Congress, it was for a time held by many that the rule established for England was to be received in the United States, the effect of which was to exclude from the jurisdiction of the General Government not only the waters of the Mississippi, but also those of the Great Lakes. To this construction it was with truth objected that, in so far as concerns the lakes, they are in fact seas, although of freshwater; that they are the natural marine communications between a series of populous States and between them and the possessions of a foreign nation; that they are actually navigated by ships of commerce of the largest capacity; that they had once been and might again be the scene of foreign war; and that therefore it was doing violence to all reason to undertake by means of an arbitrary doctrine of technical foreign law to exclude such waters from the jurisdiction of the General Government. In regard to the river Mississippi, it was objected that to draw a line across that river at the point of ebb and flood of tide, and say that the part below was public navigable water and the part above not, while in the latter the water was at least equally deep and navigable and its commerce as rich as in the former, with numerous ports of foreign entry and delivery, was to sanction a distinction artificial and unjust, because regardless of the real fact of navigability.
We may conceive that some such considerations led to the enactment in the year 1845 of an act in addition to that of 1789, declaring that—
The district courts of the United States shall have, possess, and exercise the same jurisdiction in matters of contract and tort arising in, upon, or concerning steamboats and other vessels of 20 tons burden and upward, enrolled and licensed for the coasting trade and at the time employed in business of commerce and navigation between ports and places in different States and Territories upon the lakes and navigable waters connecting said lakes, as is now possessed and exercised by the said courts in cases of the like steamboats and other vessels employed in navigation and commerce upon the high seas or tide waters within the admiralty and maritime jurisdiction of the United States.
It is observable that the act of 1789 applies the jurisdiction of the United States to all "waters which are navigable from the sea" for vessels of 10 tons burden, and that of 1845 extends the jurisdiction to enrolled vessels of 20 tons burden, on the lakes and navigable waters connecting said lakes, though not waters navigable from the sea, provided such vessels be employed between places in different States and Territories.
Thus it appears that these provisions of law in effect prescribe conditions by which to determine whether any waters are public navigable waters, subject to the authority of the Federal Government. The conditions include all waters, whether salt or fresh, and whether of sea, lake, or river, provided they be capable of navigation by vessels of a certain tonnage, and for commerce either between the United States and foreign countries or between any two or more of the States or Territories of the Union. This excludes water wholly within any particular State, and not used as the means of commercial communication with any other State, and subject to be improved or obstructed at will by the State within which it may happen to be.
The constitutionality of these provisions of statute has been called in question. Their constitutionality has been maintained, however, by repeated decisions of the Supreme Court of the United States, and they are therefore the law of the land by the concurrent act of the legislative, the executive, and the judicial departments of the Government. Regarded as affording a criterion of what is navigable water, and as such subject to the maritime jurisdiction of the Supreme Court and of Congress, these acts are objectionable in this, that the rule of navigability is an arbitrary one, that Congress may repeal the present rule and adopt a new one, and that thus a legislative definition will be able to restrict or enlarge the limits of constitutional power. Yet this variableness of standard seems inherent in the nature of things. At any rate, neither the First Congress, composed of the statesmen of the era when the Constitution was adopted, nor any subsequent Congress has afforded us the means of attaining greater precision of construction as to this part of the Constitution.
This reflection may serve to relieve from undeserved reproach an idea of one of the greatest men of the Republic—President Jackson. He, seeking amid all the difficulties of the subject for some practical rule of action in regard to appropriations for the improvement of rivers and harbors, prescribed for his own official conduct the rule of confining such appropriations to "places below the ports of entry or delivery established by law." He saw clearly, as the authors of the above-mentioned acts of 1789 and 1845 did, that there is no inflexible natural line of discrimination between what is national and what local by means of which to determine absolutely and unerringly at what point on a river the jurisdiction of the United States shall end. He perceived, and of course admitted, that the Constitution, while conferring on the General Government some power of action to render navigation safe and easy, had of necessity left to Congress much of discretion in this matter. He confided in the patriotism of Congress to exercise that discretion wisely, not permitting himself to suppose it possible that a port of entry or delivery would ever be established by law for the express and only purpose of evading the Constitution.
It remains, therefore, to consider the question of the measure of discretion in the exercise by Congress of the power to provide for the improvement of rivers and harbors, and also that of the legitimate responsibility of the Executive in the same relation.
In matters of legislation of the most unquestionable constitutionality it is always material to consider what amount of public money shall be appropriated for any particular object. The same consideration applies with augmented force to a class of appropriations which are in their nature peculiarly prone to run to excess, and which, being made in the exercise of incidental powers, have intrinsic tendency to overstep the bounds of constitutionality.
If an appropriation for improving the navigability of a river or deepening or protecting a harbor have reference to military or naval purposes, then its rightfulness, whether in amount or in the objects to which it is applied, depends, manifestly, on the military or naval exigency; and the subject-matter affords its own measure of legislative discretion. But if the appropriation for such an object have no distinct relation to the military or naval wants of the country, and is wholly, or even mainly, intended to promote the revenue from commerce, then the very vagueness of the proposed purpose of the expenditure constitutes a perpetual admonition of reserve and caution. Through disregard of this it is undeniable that in many cases appropriations of this nature have been made unwisely, without accomplishing beneficial results commensurate with the cost, and sometimes for evil rather than good, independently of their dubious relation to the Constitution.