The bounds assigned to the new Province of Quebec to the south by the proclamation of 7th October, 1763, are as follows: 

“The line, crossing the river St. Lawrence and the Lake Champlain in 45 deg. of north latitude, passes along the highlands which divide the rivers that empty themselves into the St. Lawrence from those which fall into the sea, and also along the north coast of the Bay des Chaleurs and the Gulf of St. Lawrence to Cape Rosieres,” etc.

In the same month of October, 1763, the limits of the royal Province of Nova Scotia are fixed, in the commission to Governor Wilmot, on the west “by the said river St. Croix to its source, and by a line drawn due north from thence to the southern boundary of our Province of Quebec; to the northward, by the same boundary, as far as the western extremity of the Bay des Chaleurs.”

Here, then, we find the first mention in an English dress of the line to be drawn due north from the source of the St. Croix.  There is no evidence that it was a translation of the terms in the grant to Sir William Alexander, but if it were it was made not by Americans, but by Englishmen; and not only made, but set forth under the high authority of the royal sign manual and authenticated by the great seal of the United Kingdom of England and Scotland.

The due north line from the source of the St. Croix, meeting the south bounds of the Province of Quebec, forms two angles.  One of these was the northeast angle of the Province of Sagadahock; the other is the northwest angle of Nova Scotia.  It aright be debated which of the streams that fall into Passamaquoddy Bay was the true St. Croix, but such a question could be settled by reference to evidence, and has been thus settled by the award of the commissioners under the fifth article of Jay’s treaty.  Among the many branches of a stream it may for a moment be doubted which is to be considered as its principal source, but this can be ascertained by proper methods, and it has been ascertained and marked with a monument by the same commissioners.  The tracing of a meridian line may be a difficult operation in practical surveying, but it can be effected by proper instruments and adequate skill, and this task has in fact been performed by one of the present commissioners, after being attempted by the surveyors under the fifth article of the treaty of Ghent.  The highlands are defined in the commission of Governor Wilmot and the proclamation of 1763 beyond the possibility of doubt.  They are on the north shore of the Bay of Chaleurs as described in the one instrument, and on the western extremity of that bay as described by the other.  They can therefore be found, and they have been found.