The French, by virtue of having thus discovered the mouth of the Mississippi, of having ascended it more than fifteen hundred miles, of having explored the Ohio, the Wabash, and the Illinois, from their respective mouths to their most remote sources, and of having formed several settlements as above mentioned, laid claim to the whole country drained by the main river and its tributaries. They accordingly built forts at Le Boeuf, high up the Alleghany river, and on the site where Pittsburgh now stands. On the ground of discovery or settlement, Great Britain had not the slightest claim. General, then Colonel Washington, was the first who, at the age of twenty-two, and in the year 1754, planted the British banner on the Western waters. The British claim was founded principally on the ground of contiguity, enforced by other considerations. The strongest of these was, that it could not consist with natural law, that the British colonies, with a population of near two millions, should be confined to the narrow belt of land between the Atlantic and the Alleghany Mountains, and that the right derived from the discovery of the main river should be carried to such an extent as to allow the French colonies, with a population of fifty thousand, rightfully to claim the whole valley of the Mississippi. The contest was decided by the sword. By the treaty of peace of 1763, the Mississippi, with the exception of New Orleans and its immediate vicinity, was made the boundary. The French not only lost all that part of the valley which lay east of that river, but they were compelled to cede Canada to Great Britain. It may, however, happen that all the various claims from which a title may be derived, instead of pertaining to several Powers, and giving rise to conflicting pretensions, are united and rightfully belong to one nation alone. This union, if entire, may justly be considered as giving a complete and exclusive title to the sovereignty of that part of the country embraced by such united claims. The position assumed by the British Government, that those various claims exclude each other, and that the assertion of one forbids an appeal to the others, is obviously untenable. All that can be said in that respect is, that if any one claim is alone sufficient to establish a complete and indisputable title, an appeal to others is superfluous. Thus far, and no farther, can the objection be maintained. The argument on the part of the United States in reality was, that the Government considered the title derived from the ancient exclusive Spanish claim as indisputable; but that, if this was denied, all the other just claims of the United States taken together constituted a complete title, or at least far superior to any that could be adduced on the part of Great Britain.