If the contract between the parties was clear and unequivocal, that the sale and delivery of the horse and *229wagon should operate as payment and extinguishment of the note, the case of Fuller v. Shattuck, 13 Gray, 70, would apply, and the plaintiff could not recover anything more than the balance due him over and above the amount due on the note. But the report does not show that this was the contract. The testimony at the trial was, that “ the defendant agreed to buy and did buy of the plaintiff the horse and carriage, at the price of one hundred and sixty-five dollars, which was to be paid, not in money, but by giving up the note and paying in cash any balance that might be left between this price and the amount due upon the note.” If this is a correct statement of the agreement of the parties, the contract was executory, and some further act remained to be done before either debt could operate as payment and ex-tinguishment of the other, in whole or in part. The defendant was to give up the note in part payment of the horse and carriage, and the plaintiff was to receive it instead of the same amount in cash. But until the contract was executed, neither debt would operate as a technical payment of the other. Cary v. Bancroft, 14 Pick. 315. It was clearly competent for the jury to find, upon the evidence, that the contract was an executory one, which did not extinguish the note; and therefore the ruling at the trial, that the horse and carriage were given and sold to the defendant in payment of the note, was erroneous.