205 N.W. 776 UNION MORTGAGE COMPANY, Appellee, v. W.E. EVANS et al., Appellants. Supreme Court of Iowa. November 17, 1925. EVIDENCE: Parol as Affecting Writings — Contradicting Method of Payment. A promissory note “payable in gold coin of the United States” may not be modified by a parol agreement, contemporaneous with the execution of the […]