Quincy. Aug. 13. 1825
In reply to your question, upon what map did the Commissioners trace the boundary line described in the Treaty of 1783—I answer that it was Mitchells map.
And to your question, whether by the Long Lake intended by the treaty was meant the Long Lake laid down in Mitchells Map,—I answer, that it was, & that we used no other authority for places named in the description of the boundary line than Mitchells map.
Your Obt. Sert
Signed in presence of Wm. E. Payne
Printed Source--Joseph Delafield, The Unfortified Boundary (New York: 1943)..