The principle which necessarily controls tbe questions arising upon the bill of exceptions in this case, is, that a liability evidenced by a written contract cannot be discharged by an executory parol agreement. Adams v. Nichols, 19 Pick. 275. It is unnecessary in tbe present case, to decide whether the contract which the defendant’s evidence tends to show, and on which be relied for bis defence, was valid or not. Conceding it to be valid, until it was executed it could afford no defence to tbe note. Tbe charge of tbe court as given to tbe jury seems to recognize this principle,
The judgment of the court below is consequently affirmed.