The opinion of the court was delivered by

On the question of estoppel, we entirely agree with the opinion of Judge Hare, in Battin v. Spencer, as cited in the paper-books. If the covenant of the defendant, expressed in the strongest and most comprehensive terms, be not sufficient to silence his defence, no language could have been employed that would preclude it.

We think the court was in no error in referring to the jury the question whether the reissued patent was for the same invention; but if they were, we see not how the defendant could avail himself of the attempted defence in the face of his solemn covenant. The estoppel applies itself as well to the objection against the reissue, as to that against the originality of the invention.

Nor was the defence, under the plea of non est factum, any more fortunate. The agreement of counsel estopped that. They *525had stipulated in writing that the instrument sued on need not be proved, but that, it should be read in evidence “ as if execution and delivery had been duly proved.” Due proof of execution and delivery would have established the authority of one partner to bind the firm under seal, or else the adoption and ratification of the seal by both partners; and what such proof would have done, the counsel accomplished by their agreement.

We see no errors in the record, and therefore the judgment is afiirmed.