Denio, Oh. J.

The determination of this case involves two questions: first, whether the defendant was entitled to go into a preliminary inquiry to ascertain whether the witness, Mrs. Seeley, was competent to testify for the plaintiff upon the issue, before she was sworn in chief; and secondly, whether the.defendant was entitled, under the pleadings, to go into evidence to show that the note of $90.39 was given under a mistake of fact. On both points the referee ruled against the defendant, and in both instances he was, in my opinion, wrong.

I. The point upon which the defendant objected against Mrs. Seeley as a witness was, that she was the wife of Nehemiah Seeley, and that the said Nehemiah was the party for whose immediate benefit the suit was prosecuted. The objection was not put in these precise words, but that was the effect of it. The case states that the defendant insisted that she was “the wife of the real plaintiff in interest.” The defendant asked that she might be sworn on her voir dire. This was refused; and after it had appeared by her *546 examination in chief that she was If. Seeley’s wife, the defendant offered to prove that IT. Seeley was the real owner of the note, and that the suit was brought for his sole benefit. This the referee refused, and he persisted in allowing the plaintiff to examine Mrs. Seejey in chief before the question was determined whether she was a competent witness or not. If the defendant’s position had been limited to the allegation that the witness was If. Seeley’s wife., then, inasmuch as she admitted that fact on the plaintiff’s examination, immediately after being sworn in chief, and the defendant was allowed an opportunity of objecting to her further examination, and did object, and the question arising upon that objection was correctly determined as the case then stood, no prejudice would have arisen out of the refusal to administer the preliminary oath, and the judgment should not be disturbed for that reason. But it was a part of the defendant’s objection that If. Seeley was the real plaintiff, and this the defendant offered to prove, first by the preliminary examination of the witness on the voir dire, and, when that was refused, by other witnesses. This request, in both forms, was denied to him. The referee ruled, in effect, that she should be examined in the first instance by the plaintiff on the merits, after which she might be examined by the defendant’s counsel as to her competency. This was inverting the regular order of proceeding, and was obviously incorrect. Previous to the witness being sworn, it is competent for the counsel for the party against whom he is called to have him examined on the voir dire, in order to ascertain whether he is competent to testify. (Stephens’ N. P., 1731, 1769; C. & Hill’s Notes, 257.) This well settled rule has not been departed from, as the opinion in the supreme court intimates, in modern cases. The principle, in respect to which the rigor of the ancient practice has been relaxed, is the one which precluded the party who had suffered an adverse witness to be sworn in chief from afterwards objecting to his compe *547 tency on the ground of interest, though such interest should appear in the course of the examination in chief. At present, if it appear at any time during the examination oí the witness that he is incompetent, the objection may be taken, and the testimony will be expunged. (1 Phil. Ev., 207; Jacobs v. Layborn, 11 Mees. & Welsb., 685.) But there are still cases in which it may be expedient for a party to put an adverse witness on the voir dire. For instance, if the interest arises upon written documents, with which the witness is cognizant, but which are not present, their contents may be shown by parol upon the preliminary examination, but not after the witness has been sworn in chief. (1 Phil. Ev., id.; Cow. & Hill’s Notes, 709.) The tenacity with which the old rule has been adhered to, even in modem times, is strikingly shown in a curious case in the English court of exchequer, decided in 1839. In an action on a bill of exchange, the plaintiff put a witness upon the stand whom he called James Dewdney. After he had been examined, without objection, it was ascertained that he was really George Dewdney, the plaintiff in the suit. The defendant offered to call witnesses to that fact, but on an objection that it was not one of the issues to be tried, the evidence was excluded, and the plaintiff had a verdict. On a motion for a new trial the court said : “ The regular way, although in some instances the strict course may have been improperly departed from, was for you to make this objection on the voir dire, when other evidence might have been called, if necessary, to prove the incompetency, and then, if the incompetency were established, an opportunity would be afforded to the plaintiff of proving his case by other evidence.” (Dewdney v. Palmer, 4 Mees. & Welsb., 664.) I do not say this is a case suitable to be followed by us, and it will presently be seen that it has been overruled in the court in which it was decided. But it shows plainly enough that the rule permitting, at least, the examination of a person called as a witness on his voir dire, when the right is *548 claimed by the adverse party, is not abolished in England, The effect of neglecting to insist on the preliminary oath was carefully examined in Jacobs v. Layborn, supra, where the interest was first discovered in the course of the examination, after the witness had been sworn in chief. It was held, notwithstanding the decision in Dewdney v. Palmer, not to be too late to object; but there was not in that case, or in any one which I have been able to find, an intimation that the right to the preliminary examination, when insisted on, could be denied. I conclude, therefore, that the referee fell into an error in refusing to permit the witness to be examined on the voir dire.

II. The defendant offered to show that the principal note sued on was given for a debt owing by the maker to the payee, and that by an error in computation it was given for $40.96 more than was due. This evidence was excluded on the ground that it was not within the issue made by the pleadings. The alleged mistake was set up in the answer and denied by the reply. If the allegation in that respect was too general in its terms, the remedy of the plaintiff was, by a motion under section 160, to compel the defendant to make it more certain. (The People v. Ryder, 2 Kern., 433.) By omitting to do this, and especially by replying as though he understood what was intended to be set up, he was precluded from objecting to the evidence on the trial.

The judgment must be reversed and a new trial ordered

Hubbard, J., also delivered an opinion in favor of reversing the judgment, on the same grounds stated in the foregoing opinion.

Judgment reversed.