Government went into effect was that of August 7, 1789, providing "for the establishment and support of light-houses, beacons, buoys, and public piers." Under this act the expenses for the maintenance of all such erections then in existence were to be paid by the Federal Government and provision was made for the cession of jurisdiction over them by the respective States to the United States. In every case since before a light-house could be built a previous cession of jurisdiction has been required. This practice doubtless originated from that clause of the Constitution authorizing Congress "to exercise exclusive legislation ... over all places purchased by the consent of the legislature of the State in which the same shall be, for the erection of forts, magazines, arsenals, dockyards, and other _needful buildings_." Among these "_needful buildings_" light-houses must in fact have been included. The bare statement of these facts is sufficient to prove that no analogy exists between the power to erect a light-house as a "needful building" and that to deepen the channel of a river. In what I have said I do not mean to intimate a doubt of the power of Congress to construct such internal improvements as may be essentially necessary for defense and protection against the invasion of a foreign enemy. The power to declare war and, the obligation to protect each State against invasion clearly cover such cases. It will scarcely be claimed, however, that the improvement of the St. Clair River is within this category. This river is the boundary line between the United States and the British Province of Upper Canada. Any improvement of its navigation, therefore, which we could make for purposes of war would equally inure to the benefit of Great Britain, the only enemy which could possibly confront us in that quarter. War would be a sad calamity for both nations, but should it ever, unhappily, exist, the battles will not be fought on the St. Clair River or on the lakes with which it communicates. JAMES BUCHANAN. WASHINGTON, _February 6, 1860_. _To the Senate of the United States_: On the last day of the last session of Congress a resolution, which had passed both Houses, "in relation to removal of obstructions to navigation in the mouth of the Mississippi River" was presented to me for approval. I have retained this resolution because it was presented to me at a period when it was impossible to give the subject that examination to which it appeared to be entitled. I need not repeat the views on this point presented in the introductory portion of my message to the Senate of the 2d [1st] instant.