The President had perceived, Mr. McLane said, in all the previous efforts to adjust the boundary in accordance with the terms of the treaty of 1783 that a natural and uniform rule in the settlement of disputed questions of location had been quite overlooked; that the chief, if not only, difficulty arose from a supposed necessity of finding highlands corresponding with the treaty description in a due north line from the monument, but it was plain that if such highlands could be anywhere discovered it would be a legal execution of the treaty to draw a line to them from the head of the St. Croix without regard to the precise course given in the treaty. It therefore became his duty to urge the adoption of this principle upon the Government of His Britannic Majesty as perhaps the best expedient which remained for ascertaining the boundary of the treaty of 1783. The Secretary could not perceive in the plan proposed anything so complicated as Sir Charles appeared to suppose. On the contrary, it was recommended to approbation and confidence by its entire simplicity. It chiefly required the discovery of the highlands called for by the treaty, and the mode of reaching them upon the principle suggested was so simple that no observations could make it plainer. The difficulty of discovering such highlands, Mr. McLane said, was presumed not to be insuperable. The arbiter himself was not understood to have found it impracticable to discover highlands answering the description of the highlands of the treaty, though unable to find them due north from the monument; and certainly it could not be more difficult for commissioners on the spot to arrive at a conclusion satisfactory to their own judgment as to the locality of the highlands. Mr. McLane, in answer to Sir Charles's request for information on the subject, stated that the difficulty in the way of the adoption of the line recommended by the arbiter was the want of authority in the Government of the United States to agree to a line not only confessedly different from the line called for by the treaty, but which would deprive the State of Maine of a portion of territory to which she would be entitled according to the line of the definitive treaty; that by the President's proposition a commission would be raised, not to establish a new line differing from the treaty of 1783, but to determine what the true and original boundary was and in which of the two disagreeing parties the right to the disputed territory originally was; that for this purpose the authority of the original commissioners, if they could have agreed, was complete under the Ghent treaty, and that of the new commission proposed to be constituted could not be less.