Mr. Justice Green
delivered the opinion of the Court,
The jury have found by their verdict that Boyd did the plastering sufficiently well to earn his money. It is true that Bye declined to give him a certificate of approval, but what of that? It is by no means clear that a certificate of approval was an indispensable pre-requisite before Boyd could, claim payment, but if it were, there was testimony enough to justify the inference that it was not given, not because Bye did not think it was deserved, but because Whelen, under whose orders he was acting, would not permit him to give it; and if so, the law is settled that he can not take advantage of his own or his agent's wrong. We see nothing then in this point which would warrant us in disturbing the judgment.
Nor is there anything in the contention that under the papers of October, 18th, 1878, Boyd was to be paid $3,000 only in case Asay did what was necessary to entitle him to receive the $3,600 mortgage. It is true that in the first of these two papers Asay recites that he has assigned to Boyd his right to said mortgage, “ so soon as I shall be entitled to receive and demand the same under my contract to complete the twelve houses, &c. He could assign nothing else so far as *233tills mortgage was concerned, for lie had nothing else to assign _but when we comp to the consideration for which, by this same paper, lie releases Whelen from his obligation to deliver to him this mortgage, we find that it was, “ of his paying to said Alexander Boyd such sum as may become due for plastering as the work is performed and completed from time to time, not exceeding in all the sum of $3,000 in each payment, at which price the said Alexander Boyd has sold the said mortgage.” That is, Boyd is to be paid cash from time to time, not to exceed $3000 in all, as his work — -plastering—not Asay’s work, the building of the houses, is performed and completed. And the second of these papers, by which Boyd assigned to Whelen’s wife'what Asay had assigned to him, explains why he had sold for $3,000 in cash his right to the $3,600 mortgage, viz, “ I having sold my claim to said mortgage, for the sum of $3,000, which is more valuable to me than the said mortgage when earned'under Asay’s contract with Edward, S. Wheeler.” If, as contended by the plaintiff in error, Boyd would be entitled to be paid only when the mortgage should be “ earned under Asay’s contract, then the plain language of these-papers must be ignored, and we are at a loss to know for what Boyd paid or abated $600 in the price of his work; unless, which seems incredible, he was paying or abating this sum for the privilege of retaining the risk which the papers show he intended to avoid. These papers were drafted by Whelen, and are to be read together as explanatory and expressive of the arrangement between him and Asay and Boyd; and so read, we cannot doubt that it was understood that Boyd undertook to do the plastering in consideration that he should be paid as and when his own work was done, independently of the fact whether the work contracted to be done by Asay was done well, or in time, or at all.
But conceding this, it is further contended that there is a set-off, in the shape of a bond (whether of indemnity or guaranty) in winch Boyd is one of the obligors, which had become payable by reason of Asay’s default under his building contract with Whelen. But, according to the evidence Asay had made actual or essential default, and while Boyd was going on with the plastering, Asay finding or fearing that he would be “unable to fulfill his contract,” made another agreement,. April 8th, 1879, with Whelen, as to the finishing of the said houses, differing materially from the original contract, and in pursuance of which Asay conveyed the said lots and houses to Whelen’s son as security for Whelen. This was done, as far as appears, without the knowledge or consent of the obligors in the bond. It is true that Whelen notified them of Asay’s inability to fulfill his contract, and called their attention to *234their obligation to complete the said houses, but this was not until April 23d, 1879, fifteen days after Wlielen had made his new contract with Asay, had taken conveyance of the property to his own son as security, had iu effect, if not in very terms, released Asay from the original contract, and when, therefore, the obligors had become released from the obligation of their bond. Why, if Wlielen intended to look to the bond, he thus made this new contract it is not easjr to understand. It was not merely taking additional security, it was making a new contract with substituted security. When Asay made default, if he did make actual default, Wlielen’s remedy on the bond was complete, and the cases cited by the plaintiff in error would apply. If the obligors had omitted or refused to fulfil their covenant he could have brought suit against them and recovered damages to .the extent of the injury suffered or loss sustained. But he did not. Before, so far as appears, there ivas any operative default upon the part of Asay, or any knowledge by the obligors of his immediate or prospective inability to go on, Wlielen, without their consent, without calling upon them or affording them an opportunity to fulfil their covenant, entered into a new contract with Asay which not only prevented them from doing so, but would have made them trespassers if they had attempted to do so. A new contract to perform on different terms, the unperformed part of the old contract, which took the place of the unperformed part of the old contract, and which, under the settled law, released them from performing it, and of course from all damages, under their bond, because it was not performed. If the obligors are “allowed to escape, scot free,” it is because the plaintiff in error did not choose to hold them when they could have been held. Without going into the question as to whether, if the set-off had been admitted, the money expended by the defendant below in finishing the houses would have been the proper measure of damages under the circumstances, we think that the judgment was right.
Judgment affirmed.