“Where it clearly appears that a witness has made a mistake in giving his testimony in a material point in the cause, the court may in its discretion grant a new trial.” Coddington v. Hunt, 6 Hill, 595; 3 Wait, Pr. 415. There is no doubt that the witness Van Pelt misunderstood the question put to him, and gave an answer the very opposite of that which he would have given if he had answered understandingly. The answer was vital in its importance, for upon it the jury were warranted in finding that the plaintiff had substantially performed her contract, and that the defects in the dress were slight, and easily corrected. The case was fairly tried, and the charge of the jury was full, clear, impartial, and instructive, but we doubt if justice was done, and therefore reverse the judgment, and order a new trial. But, as we are granting a favor, we must award the costs of the appeal to the respondent, though they will abide the event of the action.