The importance, however, of this port results mainly from its geographical position, and the influence it is likely to exert as a military and naval depot upon our commercial interests in the Pacific. The port of San Francisco, in Upper California, should be well fortified, and every care taken to make it a harbor of refuge for our merchant and military marine, in case of a maritime war; but it must be remembered that that place is nearly fifteen hundred miles from the nearest port of Mexico, and that it is very far north of some of the best whaling grounds in the Pacific, and too distant to afford much protection to our commerce with Central America, although its position gives it a controlling influence over the commerce of Sandwich Islands, Upper California, and Oregon. In the same way a well-fortified naval station at La Paz, from its immediate proximity to the coast of Mexico, would have a most beneficial influence on our commercial and whaling interest in this part of the Pacific. The great value, in time of maritime war, of such _key_ points as La Paz, and the commanding influence exercised by them in the protection of commerce, have become settled principles in military defence; and England shows her appreciation of their truth, and the wisdom of her own policy, in establishing stations and points like St. Helena, Cape of Good Hope, Gibraltar, Malta, Corfu, and Bermuda. Again, the growing commerce of California and Oregon, and the political importance of our possessions on the Pacific, render it necessary that we should have some means of rapid communication between them and the seat of government at Washington. This communication must be effected by the isthmus of Panama or of Tehuantepec. In either case steamers bound to Upper California and the Columbia River must have one or more intermediate depots of fuel; and in time of war it is important that these depots be established in our own rather than in a hostile territory. A glance at the map will show that La Paz is nearly equidistant from the extremities of this line; and that Tehuantepec, La Paz, and San Francisco divide into four equal parts the whole distance from Panama to Oregon. Moreover, as this ocean is peculiarly suited to steam navigation, a large part of the commerce of the Pacific must eventually be carried on in steam vessels; and in all probability not many years will elapse before a portion of our naval force in these waters is of the same character. Under this supposition, the importance of our possessing some naval depot and harbor of refuge and repair south of Upper California is too manifest to require argument or illustration.