warranty, there can be no mistake of fact when no such fact exists, or, if in existence, neither party knew of it, or could know of it; and that is precisely this case. If the owner of a Hambletonian horse had speeded him, and was only able to make him go a mile in three minutes, and should sell him to another, believing that was his greatest speed, for $300, when the purchaser believed he could go much faster, and made the purchase for that sum, and a few days thereafter, under more favorable circumstances, the horse was driven a mile in 2 min. 16 sec., and was found to be worth$20,000, I hardly think it would be held, either at law or in equity, by any one, that the seller in such case could rescind the contract. The same legal principles apply in each case.

In this case neither party knew the actual quality and condition of this cow at the time of the sale. The defendants say, or rather said, to the plaintiff, "they had a few head left on their farm in Greenfield, and asked plaintiff to go and see them, stating to plaintiff that in all probability they were sterile and would not breed." Plaintiff did go as requested, and found there these cows, including the one purchased, with a bull. The cow had been exposed, but neither knew she was with calf or whether she would breed. The defendants thought she would not, but the plaintiff says that he thought she could be made to breed, but believed she was not with calf. The defendants sold the cow for what they believed her to be, and the plaintiff bought her as he believed she was, after the statements made by the defendants. No conditions whatever were attached to the terms of sale by either party. It was in fact as absolute as it could well be made, and I know of no precedent as authority by which this court can alter the contract thus made by these parties in writing,-- interpolate in it a condition by which, if the defendants should be mistaken in their belief that the cow was barren, she could be returned to them and their contract should be annulled. It is not the duty of courts to destroy contracts when called upon to enforce them, after they have been legally made. There was no mistake of any material fact by either of the parties in the case as would license the vendors to rescind. There was no difference between the parties, nor misapprehension, as to the substance of the thing bargained for, which was a cow supposed to be barren by one party, and believed not to be by the other. As to the quality of the animal, subsequently developed, both parties were equally ignorant, and as to this each party took his chances. If this were not the law, there would be no safety in purchasing this kind of stock.

I entirely agree with my brethren that the right to rescind occurs whenever "the thing actually delivered or received is different in substance from the thing bargained for, and intended to be sold; but if it be only a difference in some quality or accident, even though the misapprehension may have been the actuating motive" of the parties in making the contract, yet it will remain binding. In this case the cow sold was the one delivered. What might or might not happen to her after the sale formed no element in the contract. . . .

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