delivered the opinion of the court, Mr. Justice ’Wheeleb not sitting, having been of counsel in the court below.

This suit was brought on a written contract under seal. In the court below the defendant, who is the appellant, offered parol evidence to vary and change the contract, but his evidence was rejected, and in doing so we believe the court below did not err. The doctrine is well settled, that such testimony may be received to explain an ambiguity and show what the parties-really meant by the language used: but when there is no ambiguity such testimony is wholly inadmissible. To permit such testimony would be to allow the contract to be reformed by trusting to the frail memory of witnesses, in contradiction to the written evidence made at the time.

There is another ground on which the appellant relies to reverse the judgment. It is that there was no sufficient consideration to support the obligation, and that this is apparent-from the face' of the contract. The contract shows that the undertaking .was in consideration that the plaintiff would *456become a substitute for the defendant’s step-son, who had been drafted for a tour of military service under a call from the executive. The court below charged the jury, that from the relation in which a step-son stands to his step-father, the relieving the step-son from a service he had been called to perform was a good and valid consideration. . We are bound, the record not showing anything to the contrary, to presume that tbe step-son was a minor, and under the guardianship of his step-father; and if so, the consideration was clearly a good and valid one.

The jury found a verdict for the plaintiff for one hundred and fifty dollars and cost. The judgment was for the one hundred and fifty dollars and interest, and all costs. So much of the judgment as relates to the interest is not in conformity with the verdict. It must be remitted, or the judgment will be reformed in this court, and rendered for the one hundred and fifty dollars and costs, in conformity with the verdict of the jury.