Cope, J. delivered the opinion of the Court Field, C. J. concurring. English was a competent witness for the plaintiffs. His interest in the result of the controversy, if he had any, was not sufficient to exclude him. The dispute related to matters in which he acted in the capacity of agent, and he was the only person from whom a knowledge of the transaction could he obtained. His testimony was admissible, ex.necessitate ; and we understand the competency of an agent in such cases to be well settled.

His competency has always been regarded as constituting an exception to the rule of exclusion on account of interest. This exception has been so often recognized by the Courts, and is so well understood by the profession generally, that we do not consider it necessary to elaborate the point. The authorities upon the subject are cited in the notes to Phillips on Evidence (4 Am. Ed. 3 vol. 106). Parol evidence was properly admitted to prove a waiver of demand upon the maker for the payment of the notes in suit.

The indorsement upon the notes embraced but one branch of the agreement, and there was nothing improper in showing that fact by parol. The evidence introduced for that purpose did not contradict or vary the terms of the written statement. Demand and notice were both waived, and in respect to the latter the waiver was reduced to writing. As to the former, it rests entirely in the verbal understanding of the parties. Its validity is unquestionable, and no error was committed in allowing it to be proved. The case of Drinkwater v.

Tebbetts (17 Me. 16) is directly in point. “ There was,” said the Court, “ an express waiver of notice in writing. This did not dispense with the necessity of a demand by the holder upon the maker to charge the indorser. Upon the face of the indorsement that condition remained in full force. If a waiver of both the conditions may be proved by parol, we are aware of no good reason why that kind of proof should be excluded, to show a waiver of one condition, where a waiver of the other is made a part of the indorsement itself. It produces no change in the legal obligation of the contract.” Judgment affirmed.