(After stating the foregoing facts.) The parolevidence rule precludes inquiry into the intention of the parties to an unambiguous written instrument. The court was of the opinion that the second contract between the parties was ambiguous as to the payment of interest to Mrs. Pritchett upon the sum agreed to be paid for her share in her mother’s estate. Parol evidence was allowed to show the intention of the parties, and the jury were instructed concerning its effect; and these rulings are the subject-matter of the exceptions. We do not think that the second contract is ambiguous, or discloses indication that it was intended to supersede the first. On the contrary, the second contract is both supplementary to and complementary of the first. The purpose of both contracts was to include in the administration of John M. Stubbs’s estate the one-fifth share of Mrs. Pritchett, inherited from her mother. In the first contract the administrators and heirs of John M. Stubbs agreed, in consideration of Mrs. Pritchett’s permitting her one-fifth share in the land which she inherited from her mother to be administered as a part of the estate of her father, John M. Stubbs, to pay to her the sum of $9,500 and interest on the whole or any part unpaid after October 15, 1908. It was by virtue of this contract that the administrators took charge of Mrs. *805Pritchett’s share in her mother’s estate, and administered it as belonging to her father’s estate. The second contract could not be a full substitute for the first, for the obvious reason that it did not purport to contain any agreement by which the estate of John M. Stubbs, or his administrators, acquired title to this undivided one-fifth interest of Mrs. Pritchett. Moreover the second contract bears internal evidence that its covenants rest upon the existence of the first. It is recited in the fifth paragraph that the administrators had made a partition of the entire thirty-five acres. This division was predicated upon the basis that the estate of John M. Stubbs owned the Dublin land as an entirety. The eighth paragraph refers to an indebtedness to Mrs. Pritchett under the first contract; that is, the obligation to pay the money issuing out of the first contract. The promise of the eighth paragraph is to pay the indebtedness arising under the first contract, which was described by stating the principal of that indebtedness. Under the plain and unambiguous contracts, Mrs. Pritchett is entitled to be paid, for her share in her mother’s estate, $9,500 principal, and interest on so much of the principal as was unpaid on October 15, 1908, from that date at the rate of eight per cent, per annum. The court erred in allowing parol evidence, and in charging the jury with reference to its effect on the contracts.

Judgment reversed.