Collins–Valentine line

The Collins–Valentine line, or Valentine–Collins line, is the boundary at approximately 45 degrees north latitude that separates the province of Quebec from the states of New York and Vermont. It was surveyed and marked by survey monuments in 1771–3 by John Collins, surveyor-general of Quebec, and Thomas Valentine, a commissioner appointed by the government of New York.

Quebec had been a French colony until the conclusion of the Seven Years' War in 1763, when it became a British colony. In the 1760s, the region that would later become a state of Vermont was considered by authorities in Britain and New York to be a part of what was then called the Province of New-York, although that status was a matter of some dispute among New York, New Hampshire, Massachusetts, and the inhabitants of the disputed territory. Thus the boundary was intended to be between Quebec and New York. In the Gazetteer of the State of New York, we read that:

By royal proclamation, issued in Oct. 1763, the line 45° N. was fixed as the boundary between the provinces of Quebec and New York, and this was confirmed in council Aug. 12, 1768. The line was surveyed by Valentine and Collins, Oct. 20, 1774.

Joseph Bouchette, writing about the re-survey agreed upon in the Treaty of Ghent, states that:

In determining the geographical boundary between St. Regis and the Connecticut River, it was soon discovered that the original demarcation of the 45th parallel of north latitude widely deviated from the true course of that parallel, the position of which was carefully ascertained by the joint observations of the British and American astronomers employed on that service in 1818. It was found that the pre-existing line was drawn almost wholly north of the true geographical bearing of that circle of latitude . . . at St. Regis the old line was actually 1375 feet, statute measure, north of the 45° of north latitude, and that Ellicott's line [surveyed the previous year] was 30 feet too far north . . .

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