BLAND, P. J.
We think it is clear from the evidence, that Ealkinburg refused to accept the engine under his order of January 30, and that a new contract was made in May fol*571lowing, and that his right to make the defense he set np must be governed by the latter agreement. Under this agreement the appellant expressly warranted the engine to be a sixteen-horsepower one, but Ealkinburg testified that he knew it was not a sixteen-horsepower engine and it is contended by appellants, because he knew this fact he can not rely upon the warranty to make good that'which he knew did not exist. A warranty will not, as a general rule, cover a defect visible to the senses, or defects known to the buyer. Thompson v. Batts, 8 Mo. 710" court="Mo." date_filed="1844-07-15" href="https://app.midpage.ai/document/thompson-v-botts-6611231?utm_source=webapp" opinion_id="6611231">8 Mo. 710. Yet if the vendor clearly and unequivocally undertakes to warrant against obvious defect, he can not escape by setting up that the defect was an open one and visible to the purchaser. Samuel v. Gwin’s Estate, 49 Mo. App. and cases cited. The evidence in this case brings it, we think, clearly within the rule announced in the Samuels case. There was an express warranty by letter that the engine was a sixteen-horsepower one, and the evidence of Ealkinburg is that the engine measured for a twelve-horsepower, but with a sufficient boiler it would develop sixteen-horsepower, that he did not examine the boiler when he purchased, and knew nothing of its defects, and that he relied on the warranty and expected to get sixteen-horsepower out of the engine. The boiler was an essential part of the machinery. Its want of capacity to produce the necessary steam to develop the latent powers of the engine, rendered defective the machinery as a whole and was a substantial breach of the warranty.
II. The contention of appellant that Ealkinburg was bound to rescind or offer to rescind the contract when he discovered the defects of the machinery, to entitle him to the defense set up, is not the law in this State. On the contrary, the authorities here are that when an article is sold on an expressed or implied warranty the purchaser may, after discovering the defect, retain the article and defeat a recovery of the purchase *572price to the extent of the difference between the value as represented and its real value. St. Louis Brewing Ass’n v. McEnroe, 80 Mo. App. 429" court="Mo. Ct. App." date_filed="1899-05-08" href="https://app.midpage.ai/document/st-louis-brewing-assn-v-mcenroe-6619356?utm_source=webapp" opinion_id="6619356">80 Mo. App. 429; Miles v. Withers, 76 Mo. App. 87" court="Mo. Ct. App." date_filed="1898-05-30" href="https://app.midpage.ai/document/miles-v-withers-6619092?utm_source=webapp" opinion_id="6619092">76 Mo. App. 87; Miller v. Hunter, 82 Mo. App. 632" court="Mo. Ct. App." date_filed="1900-02-05" href="https://app.midpage.ai/document/aultman-miller--co-v-hunter-6619554?utm_source=webapp" opinion_id="6619554">82 Mo. App. 632; Compton v. Parsons, 76 Mo. 455" court="Mo." date_filed="1882-10-15" href="https://app.midpage.ai/document/compton-v-parsons-8007208?utm_source=webapp" opinion_id="8007208">76 Mo. 455; Brown v. Weldon, 99 Mo. 564" court="Mo." date_filed="1889-10-15" href="https://app.midpage.ai/document/brown-v-weldon-8009712?utm_source=webapp" opinion_id="8009712">99 Mo. 564; Schoenburg v. Loker, 88 Mo. App. 387" court="Mo. Ct. App." date_filed="1901-04-09" href="https://app.midpage.ai/document/schoenberg-v-loker-8262674?utm_source=webapp" opinion_id="8262674">88 Mo. App. 387.
III. Objections were interposed by appellant to the evidence of Weber in respect to the May agreement, on the ground that his agency was in writing which showed that he had no authority to make any changes in the order or contract of January 30. Weber’s evidence is that he was notified by Ealkinburg that the engine was a twelve-horsepower engine and that he would not receive it. That he notified appellant of this fact, .and that by letter he was directed to make the May agreement with Ealkinburg. Weber was specially authorized by appellant to make the new agreement and what he did was approved of by the appellant, by the acceptance of the fruits of the transaction — the notes — and it is in no position now to object to what it expressly authorized to be done and ratified after it was done.
We discover no reversible error in the record and affirm the judgment.
All concur.