On the trial below plaintiffs were permitted, over objection by defendant, to introduce oral testimony as to the substance of the alleged written assignment of the lease in question, without as preliminary thereto laying sufficient and proper foundation for admission of secondary evidence. Exception by appellant to this ruling is well taken. The admission of the oral testimony is prejudicial error. Ledford v. Emerson, 138 N. C., 502, 51 S. E., 42; Mahoney v. Osborne, 189 N. C., 445, 127 S. E., 533; Chair Co. v. Crawford, 193 N. C., 531, 137 S. E., 577.

“The rule excluding parol evidence as to the contents of a written instrument applies only in actions between parties to the writing and when its enforcement is the substantive cause of action,” Brown, J., in Ledford v. Emerson, supra.

*90 In tbe instant case the action is between the lessors and the alleged assignee of lessee, and the question of the assignment and its contents is directly at issue.

Other assignments of error need not be considered, as the matters to which they relate may not recur on another trial.

New trial.