Rickle v. Wyoming Valley Paper Mills

In an equitable proceeding for the cancellation of a particular document on the ground of mistake, the rule that parol evidence is inadmissible to vary or contradict the terms of a written instrument does not obtain. McIsaac v. McMurray, 77 N. H. 466, 469.

“Cancellation is appropriate when there is an apparently valid written agreement or transaction embodied in writing, while in fact, by reason of a mistake of both or one of the parties, either no agreement at all has really been made, since the minds of both parties have failed to meet upon the same matters, or else the agreement of…