In view of these portentous consequences, I can not but think that this course of legislation should be arrested, even were there nothing to forbid it in the fundamental laws of our Union.  This conclusion is fortified by the fact that the Constitution itself indicates a process by which harbors and rivers within the States may be improved—­a process not susceptible of the abuses necessarily to flow from the assumption of the power to improve them by the General Government, just in its operation, and actually practiced upon, without complaint or interruption, during more than thirty years from the organization of the present Government.

The Constitution provides that “no State shall, without the consent of Congress, lay any duty of tonnage.”  With the “consent” of Congress, such duties may be levied, collected, and expended by the States.  We are not left in the dark as to the objects of this reservation of power to the States.  The subject was fully considered by the Convention that framed the Constitution.  It appears in Mr. Madison’s report of the proceedings of that body that one object of the reservation was that the States should not be restrained from laying duties of tonnage for the purpose of clearing harbors.  Other objects were named in the debates, and among them the support of seamen.  Mr. Madison, treating on this subject in the Federalist, declares that—­

The restraint on the power of the States over imports and exports is enforced by all the arguments which prove the necessity of submitting the regulation of trade to the Federal councils.  It is needless, therefore, to remark further on this head than that the manner in which the restraint is qualified seems well calculated at once to secure to the States a reasonable discretion in providing for the conveniency of their imports and exports, and to the United States a reasonable check against the abuse of this discretion.

The States may lay tonnage duties for clearing harbors, improving rivers, or for other purposes, but are restrained from abusing the power, because before such duties can take effect the “consent” of Congress must be obtained.  Here is a safe provision for the improvement of harbors and rivers in the reserved powers of the States and in the aid they may derive from duties of tonnage levied with the consent of Congress.  Its safeguards are, that both the State legislatures and Congress have to concur in the act of raising the funds; that they are in every instance to be levied upon the commerce of those ports which are to profit by the proposed improvement; that no question of conflicting power or jurisdiction is involved; that the expenditure, being in the hands of those who are to pay the money and be immediately benefited, will be more carefully managed and more productive of good than if the funds were drawn from the National Treasury and disbursed by the officers of the General Government; that such a system will carry with it no enlargement of Federal power and patronage, and leave the States to be the sole judges of their own wants and interests, with only a conservative negative in Congress upon any abuse of the power which the States may attempt.