¶1The defendant contends that the writing introduced in evidence shows that the indebtedness was discharged. The writing dated October 14, 1898, provides for a sale of the five-eighths interest of plaintiff and said Maris in certain mining lots to the defendant for the sum of $10,000, which is stated to be “the amount of money advanced and put into all the various enterprises and mining interests, in which the said parties have hereto been interested in,-in Jasper *514county.” It is further provided that defendant Scott should have thirty days to accept and comply with the terms of said-writing. On November 11th, as we have seen, an extension óf time for twenty days was given to defendant by plaintiff and Maris on said contract “upon the'same terms and conditions.” On the 23d day of November, next thereafter, the sale of plaintiff’s interest with that of Maris to defendant was consummated, as-shown by said last-named ruling. It will be noted that this latter ruling does not include the statement .quoted from the former or preliminary writing that the consideration was the ‘ ‘ amount of money advanced .and put into all. the various enterprises and mining interests, ’ ’ of the parties.
¶2The conclusion of law by the referee, which was approved by the court, was that the writings dated October 14, 1898, and November 23, 1898, “do not contain provisions releasing claim sued for” because the latter supersedes the former and does away with its provisions.
¶3It is the law that a contract in writing, complete and perfect in itself, not ambiguous in its terms will be held to supersede a prior written contract in relation to the same subject-matter, and parol evidence will not be admitted to show that such was not the intention of the parties (McClurg v. Whitney, 82 Mo. App. 625); and that a valid contract made in substitution for a former one, annuls the obligations of the first. Pressed Brick Co. v. Barr, 76 Mo. App. 380. There can be no¡ doubt but what the first writing was a mere agreement for a sale, and that the latter contains the terms and conditions of a complete sale, and as such there being no ambiguity in its provisions it supersedes the first in toto. An inspection will show that the two vary greatly in their provisions. And as it was competent for the parties when they came to conclude the transaction to vary the terms of the preliminary agreement for sale; and having done so by writing, we do not see *515how we can hold otherwise than that the last was a complete substitution of the former.- We are forced by this conclusion to hold that the judgment of the trial court was proper on the issue as presented.
¶4Cause affirmed.