A PROMISSORY note for the payment of money executed by the plaintiff to a third person, and assigned to the defendant before the commencement of the suit, is a legal matter of set-off.

It is not necessary that a plea of payment and set-off under *185the statute, should show that the amount claimed as a set-off is equal to the plaintiff’s demand.

If such a plea be filed, and it be found on the trial that part only of the demand has been paid, the plaintiff is entitled to judgment for the residue; but if it appear that the plaintiff has received more than the amount of his claim, the defendant obtains judgment for the overplus. Rev. Code, 1831, p. 405 (1).