The population of the United States has nearly trebled during the thirty-four years which have elapsed since that in which the last war against England was declared. Their wealth and resources have increased in the same ratio; and that, in case of war, these should be brought into action as promptly as possible, admits of no doubt. Once engaged in the conflict, to make the war as efficient as possible will shorten its duration, and can alone secure honorable terms of peace. I have not the documents necessary for making an approximate estimate of the annual expenses of a war with Great Britain; and if I had, I could not at this time perform that amount of labor which is absolutely necessary in order to draw correct inferences. Taking only a general view of the subject, and considering the great difference of expense in keeping a navy in active service, between one of eight frigates and one of ten ships of the line, fourteen frigates and a competent number of steamers; that Texas and Oregon are additional objects of defence; that the extensive system of fortifications which has been adopted will require about fifteen thousand additional men; and that, in order to carry a successful and decisive war against the most vulnerable portion of the British dominions, a great disposable regular force is absolutely necessary; I am very sure that I fall below the mark in saying that, after the first year of the war, and when the resources of the country shall be fully brought into action, the annual military and naval expenses will amount to sixty or seventy millions of dollars. To this must be added the expenses for all other objects, which, for the year ending on the 30th of June, 1845, amounted to near fifteen millions, but which the Secretary of the Treasury hopes may be reduced to eleven millions and a half. The gross annual expenses for all objects will be estimated at seventy-seven millions; to be increased annually by the annual interest on each successive loan. In order to ascertain the amount of new revenue and loans required to defray that expense, the first question which arises, is the diminution of the revenue derived from customs, which will be the necessary consequence of the war.