Whether the defendant agreed to furnish the plaintiffs with lamp-black at five cents a pound in packages, or at five cents a package, was by the verdict of jury settled upon conflicting evidence at five cents a pound, and not five cents a package. There was evidence on the part of the defendant tending to show that the packages in question, though weighing only half a pound each, were known to the trade as pounds, and usually dealt in as pounds. The plaintiffs were consumers of lamp-black in making stove polish, stove putty, and other mixtures. They did not otherwise deal in the article. *782Aside from their purchase of the defendants their purchases of the article had been in bulk by actual weight. The custom for which the defendant contends is one that permits him to sell half a pound as the equivalent of a pound. Such a custom may be well known among traders, but it is one which apparently benefits the trader at the expense of the consumer, and manifestly would not be tolerated by the latter unless attended by advantages which would be compensatory of his actual loss in quantity. To bind the latter by such a custom it ought to appear that he dealt with reference to it. Boardman v. Gaillard, 1 Hun, 217; Walls v. Bailey, 49 N. Y. 464; Miller v. Burke, 68 N. Y. 615. The jury were authorized, upon the evidence, to find that the plaintiffs did not know the custom; did not deal with reference to it; paid the defendant’s bills in ignorance that they were made out on that basis, and hence paid the defendant’s overcharge in ignorance of the facts upon which it was made. It was therefore an overpayment by mistake on the part of the plaintiffs of an overcharge by the defendant, which he had no right to. make in the absence of the consent of the plaintiffs, and hence has no right to retain the amount of the overpayment. The plaintiffs had a right to rely upon the correctness of the defendant’s bills. The rule of caveat emptor does not apply to accuracy in quantity. We do not think that any negligence can be imputed to the plaintiffs in not sooner discovering the methods employed by the defendant. The bills rendered by him contained a character which the plaintiffs would read “pounds,” unless advised that it designated packages. It may be that the result is that the defendant sells his lamp-black at a loss, but it is a loss which he has brought upon himself by the use of packages deceptive in quantity, and by the use of a character in his bills rendered, equivocal in significance, both of which seem devised to benefit the vendor at the expense of the consumer. These views dispose of all the grounds of error alleged by the defendant. The judgment should be affirmed, with costs.