Opinion,
Mr. Chief Justice Paxson :There are thirty-two assignments of error in this case. A *284discussion of them in detail is impracticable. We can only refer, in a general way, to the controlling principles presented by the record.
The action in the court below was brought upon a promissory note for four thousand dollars, made by the defendant to the order of Annie M. Irvin, and by her indorsed. At the time the note was made, it was delivered to Murray & Gordon, attorneys, and had remained in their possession to the time of the trial below, when it was produced by them upon call. The circumstances under which the note was given and placed in the custody of Murray & Gordon may be briefly stated as follows:
Martha Jane Irvin, the plaintiff, was the wife of James A. Irvin. The latter was a member of the firm of John Irvin & Bros. The firm owned valuable real estate in the counties of Clearfield and Indiana, which it became the interest of the firm to sell. They contracted to sell one tract, known as the Elk Lick land, to C. B. Howard and others, for the sum of one hundred fifty thousand dollars. The appellant was requested to sign the deed with her husband, and she refused. It is not necessary to refer in detail to the subsequent litigation and proceedings which culminated in the agreement dated September 11, 1884, between the appellant and John Irvin. By the terms of this agreement, Mrs. Irvin agreed, inter alia, to execute a quit-claim deed to certain real estate described therein, and to convey to the said John Irvin, the defendant, “ all her right, title, and interest of every kind in all the remaining real estate owned by said James A. Irvin.” By the fourth clause of said agreement, it is provided as follows: “ In consideration of the foregoing, said John Irvin agrees and binds himself to pay to said Martha' Jane Irvin the sum of six thousand dollars, as follows: one thousand dollars in hand; one thousand dollars on delivery of the second deed within contemplated, to be made within twenty days; and the remaining four thousand dollars on November 1, 1885, for which he is to’ give, on the delivery of said second deed, a negotiable promissory note, with an indorser such as Murray & Gordon, her attorneys, may approve; said note to be with interest from December 1, 1884, the same to be delivered to said Murray & Gordon, as custodians for the parties hereto,” etc. And by the *285sixth paragraph, the agreement further provides that “ Said Martha Jane Irvin agrees that in any proceeding she may institute against her husband for divorce, she will not assign any other reason therefor than the desertion of her by her husband.”
Upon the face of the note in controversy, the plaintiff had no title. Her name did not appear upon it, and it was not and never had been in her possession. Upon the trial below, she called a witness to prove the signatures to the agreement, and also to identify the note as the one referred to therein. -With this proof in, her case was complete, and upon the face of the papers she vmuld have been entitled to recover, provided she had complied with the terms of the agreement. Just here occurred the first departure upon the trial in the court below. It is fully set forth in the first assignment, which is as follows : “The court erred in permitting the defendant to introduce his defence on cross-examination of Cyrus Gordon, Esq., called by plaintiff as a subscribing witness to the signatures to the contract and to identify note offered by plaintiff.” The same question was raised by a number of subsequent assignments, but they do not conform to the rules of court. The first assignment, however, enables us to rule it.
The witness was allowed, against the objection of the plaintiff, to inject the defence into the case upon cross-examination. He was called for a single purpose, viz., to prove the signatures to the agreement, and to identify the note. The witness was permitted to say: “ Well, it (the note) was left with us as custodians, and was to be held by us until the terms of the contract between them was complied with; amongst which were that she was to procure a divorce from her husband, provided he made no defence to it, or did not prevent her from procuring it.”
It will be seen that this directly contradicts the written agreement. It contains no clause by which Mrs. Irvin agreed to procure a divorce from her husband. On the contrary, she merely stipulated that in case she should proceed against him for a divorce, she would not assign any other reason than his desertion. To meet this difficulty, the defendant was permitted to prove by the cross-examination of the witness, and against objection, that it was the understanding at the time the agreement was executed that the plaintiff was to procure a divorce from her *286husband, before she would be entitled to receive the four thousand dollars; that this understanding was in parol, and was purposely omitted from the writing. It was contended, on the part of the defendant, that the divorce was the consideration or a part of the consideration of the agreement; that such a contract was against public policy, and tainted the entire transaction.
It is almost needless to observe that an ample consideration appears upon the face of the paper. The plaintiff was relinquishing valuable dower rights for a moderate compensation. She denies that any such agreement existed in regard to the divorce. Upon this point, there is a conflict of testimony which we are not required to discuss. I will observe, however, that, in our view, the paper of March 23, 1885, purporting to be signed by the plaintiff, does not strengthen the defendant’s case- upon the facts. The reference therein to the divorce is entirely consistent with what is said about it in the written agreement. It is evidence merely that she had commenced divorcé proceedings : not that she had bound herself, as a part of the consideration of the contract, to procure a divorce.
It is very clear that all this evidence was improperly received upon cross-examination. The agreement itself explained the terms upon which the note was held. If relevant at all, it was only by way of defence. We do not think, however, it was competent at any time, or for any purpose. The effect of it was to reform a written instrument executed under the hands and seals of the parties; not only to reform it, but to inject into it a stipulation which the defendant claims renders it null and void, and prevents the recovery of a valid consideration stipulated to be paid for its execution.
The principle is too well settled to need the citation of authority that, where by fraud, accident, or mistake, something is omitted from an instrument, a chancellor will reform it in accordance with the actual agreement of the parties. But neither fraud, accident, nor mistake was alleged in this case. The contention is that the alleged clause stipulating for a divorce was purposely omitted from the paper. It is in direct conflict with the written instrument. The defendant contends that it destroys it in part at least. I know of no decided case and no principle of law which permits an oral contract, made *287at the same time with a written contract under seal, and purposely omitted therefrom, to be set up not only to contradict but to destroy it. The two agreements cannot possibly stand together; one or the other must fall. When parties without fraud or mistake have put their engagements in writing, that is not only the best, but the sole evidence of their agreement. We may well be excused at this late day from entering upon an elaborate discussion of the law in relation to the admission of oral evidence to affect written instruments. It may be received to explain the subject-matter of such papers: Barnhart v. Riddle, 29 Pa. 92; to prove a consideration not mentioned in a deed, provided it be not inconsistent with the consideration expressed in it: Lewis v. Brewster, 57 Pa. 410; but not to contradict or vary the terms of the instrument itself: Martin v. Berens, 67 Pa. 459. The exception is, where there has been fraud, accident, or mistake in the making of the agreement; and, even in such ease, the instrument can be reformed only by clear, precise, and indubitable evidence of what occurred at the time of the transaction. As was well said by this court in the ease last cited, “ Where parties without any fraud or mistake have deliberately put their engagements in writing, the law declares the writing to be not only the best, but the only evidence of their agreement, and we are not disposed to relax the rule.”
When the plaintiff had proved the agreement of September 11, 1884, and had identified the note in suit, she had a clear case. There was not a trace of anything in it that offended against morality or public policy. Hence we can understand the anxiety of the defendant to inject into it, upon cross-examination, something to discolor it. liad the evidence referred to been rejected, the defendant would have been compelled to set up what he designates as an unlawful, if not immoral transaction, by way of defence. As he was a party to it, he might have found this difficult. Without expressing an opinion as to the legal effect of the transaction, it is sufficient to say that it did not properly appear in the plaintiff’s case, and her right to recover could not be defeated for such reason.
Judgment reversed, and a venire facias de novo awarded.