The term northwest angle of Nova Scotia was used in the secret instructions of Congress and is adopted in the treaty of 1783. In the instructions it is named without any explanation, as if it were a point perfectly well known. In one sense it was so, for although it never had been marked by a monument, nor perhaps visited by the foot of man, its position could be laid down upon a map; nay, was so on many existing maps, and the directions for finding it on the ground were clear and explicit. These directions are to be found in the royal proclamation of October, 1763, and in the commission to Montague Wilmot, governor of Nova Scotia, of cotemporaneous date. Any uncertainty in regard to the position of this angle which may have existed in relation to the meaning of the first of these instruments is removed by the act of Parliament of 1774, commonly called the Quebec act.
Before citing these instruments it will be proper to refer to the circumstances under which the two first were issued.
Great Britain, after a successful war, found herself in possession of the whole eastern side of the continent of North America. So much of this as lay to the south of the St. Lawrence and the forty-fifth parallel of north latitude had been previously made the subject of charters from the British Crown under a claim of right from priority of discovery.[46] The possession of this wide tract was not uncontested, and various other European nations had attempted to found settlements within the limits of the British charters. In such cases it was held as a matter of law that where the occupation or defense of the territory granted had been neglected the right had ceased, and the country, when recovered by conquest or restored by treaty, was again vested in the Crown, to be made the subject of new grants or governed as a royal colony. Thus, when the settlements made by the Dutch and Swedes, which by the fortune of war had become wholly vested in Holland, were reduced, the Crown exercised its rights by conveying them to the Duke of York, although covered in a great part, if not wholly, by previous charters; and when these countries were again occupied by the Dutch and restored by the treaty of Breda it was thought necessary that the title of the Duke of York should be restored by a fresh grant. In both of these charters to that prince was included the Province of Sagadahock, within whose chartered limits was comprised the territory at present in dispute. This Province, confined on the sea between the rivers St. Croix and Kennebec, had for its opposite limits the St. Lawrence, or, as the grant expresses it, "extending from the river of Kenebeque and so upward by the shortest course to the river Canada northward." The shortest course from the source of the Kennebec to the St. Lawrence is by the present Kennebec road. This grant therefore covered the whole space along the St. Lawrence from about the mouth of the Chaudiere River[47] to the eastern limit of the grant to Sir William Alexander. By the accession of James II, or, as some maintain, by the act of attainder, it matters not which, this Province reverted to the Crown, and was by it granted, in 1691, to the colony of Massachusetts. In the same charter Nova Scotia also was included. This has been called a war grant, as in fact it was, and the colony of Massachusetts speedily availed themselves of it by conquering the whole of the territory conveyed except the island of Cape Breton. The latter, too, fell before the unassisted arms of the New England Provinces in 1745, at a time when Great Britain was too deeply engaged in the contest of a civil war to give aid either in money or in men to her transatlantic possessions.