
    WALKER vs. GREENE.
    1. A liability evidenced by a 'written contract cannot be discharged by an executory parol agreement.
    Ekeoe to the Circuit Court of St. Clair.
    Tried before the Hon. Thomas A. Walker.
    This was an action of assumpsit by the defendant in error against the plaintiff in error, to recover the amount of a promissory note for $200, made by the defendant and one Burwell Sellars.
    On the trial a bill of exceptions was allowed, by which it appears, that the defendant below offered proof tending to show, that soon after the maturity of the note, and while Burwell Sellars, the co-maker, was still in the country, he made an agreement with the plaintiff, that the defendant was to cut two pair of. mill rocks for the plaintiff, according to particular dimensions tobe furnished by the plaintiff, estimated to be worth forty dollars, and said mill rocks were to be taken in full discharge of defendant’s liability on said note; that, sometime after this agreement was entered into, the plaintiff came into the neighborhood where defendant and Sellars lived, and said he was going to give defendant the measures for the rocks, but he departed without doing so; that the defendant remained, from the time of the agreement up to the time of trial, in the county, and still resides there. There was no proof that the rocks had been cut or delivered to tbe plaintiff, or that tbe measures bad been furnished by tbe plaintiff to tbe defendant.
    Tbe bill of exceptions states, that there was other proof in tbe cause, and conflicting, but does not state what.
    “On this state of facts, tbe court charged tbe jury, that, if tbe plaintiff bad agreed to receive, and bad actually received tbe mill rocks, in discharge of defendant’s liability, then be could not recover; but if be bad never received tbe rocks, and they were of much less value than tbe note, although be might have agreed to receive them, then they must find for tbe plaintiff.”
    To this charge defendant excepted, and asked tbe court to charge tbe jury, “that, if they believed from tbe proof that tbe plaintiff bad agreed with defendant to receive two pair of mill rocks, notwithstanding tbe rocks were of much less value than tbe note, to be cut by tbe defendant, tbe measures of which were to be afterwards furnished by plaintiff, which rocks were to be in full discharge of defendant’s liability on said note; and if plaintiff bad never furnished tbe measures of said rocks, and in tbe meantime said Sellars bad left tbe county, defendant all tbe while remaining in tbe neighbor^ hood where the rocks were to be cut, then plaintiff could not recover, and they must find for the defendant.” This charge the court refused to give, and the defendant excepted.
    The charge of the court as given, and refusal to charge as prayed, are here assigned for error.
    B. T. Pope, for plaintiff in error.
    G. Hewitt, contra.
    
   GIBBONS, J.

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, •whilst tbe charge prayed by the defendant denies it. It follows, therefore, that there was no error in the charge given, and that the charge asked was properly refused.

The judgment of the court below is consequently affirmed.  