In this category also is that part of the charge which tells the jury that if Jenkins “ knowingly permitted Dickerman to negotiate a discount of the note with Shinn,” he is bound by D.ickerman’s action and cannot recover. Dickerman was indebted to Jenkins in an amount less than the face of Shinn’s note, which Jenkins held as collateral security. If Dickerman could induce Shinn to pay his (Dickerman’s). debt to Jenkins before the Shinn note was due, upon terms-that were advantageous to Shinn, it was not the duty or the right of Jenkins to interfere, for he was bound to surrender the collateral when the debt due him was paid. He could leave Dickerman and Shinn, therefore, to their negotiation without imperilling his own rights, so long as he did nothing to lead Shinn to believe that he could discharge his note by payment to Dickerman.
But it was competent for Shinn to show that Jenkins had in fact constituted Dickerman his agent to collect the note for him, even by a parol agreement contemporaneous with the written contract of assignment, for the fact of agency is collateral to and not a contradiction of the terms of the writing. Evidence to that effect would not affect the writing as a contract, but would only show that Jenkins had appointed another to do for him what the contract authorized him to do. As the appointment of the agent carried no interest with it, it was revocable at will. But Dickerman’s contention as to the understanding between him and Jenkins would, if it prevailed, abrogate the contract of assignment, for it would lead to this: Jenkins, not being authorized to collect the note, could not prosecute the present suit if the note were unpaid, because the object of the suit is collection.
For the errors indicated the judgment must be reversed, and the cause remanded for a new trial.
It is so ordered.