Thus a clear constitutional mode exists by which the legislature of Michigan may, in its discretion, raise money to preserve the channel of the St. Clair River at its present depth or to render it deeper. A very insignificant tonnage duty on American vessels using this channel would be sufficient for the purpose; and as the St. Clair River is the boundary line between the United States and the Province of Upper Canada, the provincial British authorities would doubtless be willing to impose a similar tonnage duty on British vessels to aid in the accomplishment of this object. Indeed, the legislature of that Province have already evinced their interest on this subject by having but recently expended $20,000 on the improvement of the St. Clair flats. Even if the Constitution of the United States had conferred upon Congress the power of deepening the channel of the St. Clair River, it would be unjust to impose upon the people of the United States the entire burden, which ought to be borne jointly by the two parties having an equal interest in the work. Whenever the State of Michigan shall cease to depend on the Treasury of the United States, I doubt not that she, in conjunction with Upper Canada, will provide the necessary means for keeping this work in repair in the least expensive and most effective manner and without being burdensome to any interest. It has been contended in favor of the existence of the power to construct internal improvements that Congress have from the beginning made appropriations for light-houses, and that upon the same principle of construction they possess the power of improving harbors and deepening the channels of rivers. As an original question the authority to erect light-houses under the commercial power might be considered doubtful; but even were it more doubtful than it is I should regard it as settled after an uninterrupted exercise of the power for seventy years. Such a long and uniform practical construction of the Constitution is entitled to the highest respect, and has finally determined the question. Among the first acts which passed Congress after the Federal