It is not alleged that the mortgagors were drawn into the purchase and consequent execution of the mortgage, by the alleged assurance that the principal 'would not be called for; and this distinguishes the case from Miller v. Henderson, (10 Serg. & Rawle, 190,) and brings it within the authority of Hain v. Kalback, (14 Serg. & Rawle, 159.)- The promise not to sue seems to have been gratuitous, and intended to mean nothing—an assurance rather than an engagement. With the supposed usurious transaction between the plaintiff and a precedent terre-tenant, the present terretenant has nothing to do, and he cannot avail himself of it. Neither can he be allowed to allege that the suit is prosecuted without the authority of the party in interest. Had he suspected the fact to be so, his course was tq call on the attorney to file his warrant; but the fact itself would furnish no defence.
Judgment affirmed.