¶1The defendants in error brought action in the court below to recover damages for defects in a steam-boiler which plaintiffs in error constructed and put up for them in a vessel under a special contract. By the verdict of a jury they recovered a judgment of one thousand, dollars. Many exceptions were taken on the trial, but the only one requiring attention relates to the rule of damages. The judge instructed the jury that if, by reason of the defects the boiler was worth less than the contract price, then the plaintiffs would be entitled to recover whatever amount the boiler is worth less than the contract price. This was erroneous. He should have instructed them that plaintiffs were entitled to recover the difference in value between the boiler as it was with the defects, and the boiler as it would have been if completed in compliance with the contract. This latter sum might be more than the contract price, or it •might be less, but it was obviously the proper standard by which to measure the damages of plaintiffs, because *210a boiler so completed was exactly what they were entitled to.
¶2We say nothing concerning any special damages, because no question respecting such damages is before us.
¶3The judgment is reversed, with costs, and a new trial ordered.