Opinion by

There is no error in this record of which the appellant has reason to complain. The court below narrowed the margin of fact upon which the jury could base a verdict beyond what the case in our judgment warranted, but of this the appellant cannot complain. It was well observed in Phillips v. Meily, 106 Pa. 536, by the then Mr. Justice Paxson, that “ The English rule that parol evidence is inadmissible to vary the terms of a written instrument does not exist in this state. The cases are numerous upon this point. It is sufficient to refer to Kostenbader v. Peters, 80 Pa. 438. It would perhaps be more accurate to say that the rule has been relaxed, for the guards which this court has thrown around the modification of the rule have to some extent preserved the rule itself. In the present condition of the law of evidence public policy requires that we should do nothing to increase the facilities for destroying written instruments. As was well observed by our Brother Trunkey in the recent case of Juniata Building and Loan Association v. Hetzel, 103 Pa. 507, ‘Now that parties are competent witnesses each may oppose his oath to the other’s, and certainly when written contracts or obligations are sought to be impeached by defenses purely equitable the reason is stronger than formerly for enforcing the rules of evidence applicable to cases in equity.’ ” The rule above stated has prevailed in Pennsylvania since Herr, Lessee, v. Kirkbride, tried at nisi prius in Bucles county, March 24, 1773, which case was authoritatively reported by Mr. Chief Justice Tilghmait, in his opinion in Wallace v. Baker, 1 Binney, 610.

It was not necessary, however, to invoke this rule in the present case. It is not the case of a written instrument varied in its effect by parol testimony. It is admitted by the appellant that the letter of the 8th of September was not the contract. It is sought however to bind the appellee by the letter of the 15th of September, 1890, and by a subsequent agreement for the sale of a lot and the erection of a house dated the 10th of January, 1891, which became executed by the deed of the appellant to the appellee and the mortgage of the appellee and wife to the appellant dated the 2d of February, 1891, and to exclude entirely all that led to and induced these written evidences of a broader and more comprehensive contract. The *395appellee is bound by these writings but they do not, in our view of the case, constitute the entire contract between the appellee and the appellant. Between the letter of the 8th of September and that of the 15th of September, 1890, there was an agreement, provisional it may be, entered into between Merrit Green representing the appellant and the appellee. The letter of September 15 refers to it and seems to confirm it, with the exception therein referred to. The letter is addressed to the appellee and informs him that “ Pursuant to our conversation about the matter of employment with us would say that our people have considered the matter and think favorably of it, with this exception that if you receive the full price of $85.00 and a boy is sufficient to do the work of a fireman, they should pay suitable wages for a boy.” The exception, of course, relates to the wages of the boy, and with that the letter has to do. The offer as to wages is specific. As to all other things included in the agreement, the conversation is allowed to govern. The case, therefore instead of being that of a written agreement as to which parol testimony is sought to be introduced to vary its effect, is, in fact, a parol agreement in which the letter above referred to gives express assent, with the exception therein referred to, and the deed and mortgage simply give legal effect to the part of the agreement which would not otherwise have bound either party. Even under the English rule, where an agreement in writing is expressed in short and incomplete terms, parol evidence is admissible to explain that which is per se unintelligible, such explanation not being inconsistent with the written terms: Sweet v. Lee, 3 Man. & Gran. 450 (42 Eng. C. L. R. 240). It is very certain that the letter of the 15th of September, 1890, does not make a complete and intelligible contract in itself. Something else is necessary to its completeness, and that something is referred to in the letter itself as the conversation had between the writer of the letter and the appellee. The agreement contained in the conversation referred to is, therefore, a question of fact which must in any trial of the case be submitted to the jury. If the facts of the case had brought it within the rule in Thomas et al. v. Loose et al., 114 Pa. 35, in which it was laid down by Mr. Justice Trunkey, in an admirable opinion upon the subject, that “ parol evidence is admissible to establish a contemporaneous oral agreement which *396induced the execution of a written contract, though it may vary, change or reform the instrument. It has been often said that such oral agreement must be shown by evidence that is clear, precise and indubitable, that is, it shall be found that the witnesses are credible, that they distinctly remember the facts to which they testify, that they narrate the details exactly and that their statements are true,” the evidence would be sufficient to carry the case to the jury and justify a verdict for the appellee. Two witnesses testify to the agreement. They are corroborated by the letter of the 15th of September, and by other facts and circumstances connected with the purchase of the lot and the erection of the house mentioned by them, which appear in various ways in the testimony offered by both parties. The jury might very well therefore have found that their testimony was accurate and that the agreement was such as was claimed by the appellee and his brother. The facts of the ease, however, do not bring it within the principle of Thomas v. Loose, supra. The parol evidence is not introduced for the purpose of varying, changing or reforming the proposition contained in the letter of the 15th of September, 1890, supra. It is rather intended to supply what is manifestly lacking in that letter, in order to make the contract complete, intelligible and consistent.

It follows, from what we have said, without further discussion, that the court could not have properly answered any of the appellant’s points as requested, denying the right of the plaintiff in the court below to recover. The assignments of error are therefore all overruled and the judgment is affirmed.