In Martin v. Berens, 67 Pa. 459, it was said by the late Mr. Justice Williams, that “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. It has been found to be a wholesome one, and. now that parties are allowed to testify in their own behalf, the necessity of adhering strictly to it is all the more imperative.”

Without a wide departure from the doctrine of that and kindred cases, the court below could not have done otherwise than hold the affidavit of defence in question insufficient. The alleged parol agreement is entirely at variance with the promissory note sued on in this case. It not only changes its legal effect, but it contradicts its very terms.

There was no error in entering judgment for want of a sufficient affidavit of defence.

Judgment affirmed.