I think there was no error in permitting the witness Schwab to state, “What, in his opinion, was the difference in value of the boat then, and as she was before the collision.” He did not give an opinion founded upon the testimony of others; but from the condition of the boat, as he saw it before the injury, while unloading, and as he saw it' after the injury. He had all the science in regard to the building and value of boats necessary to render him competent to testify as to the value, and he had made an estimate of the cost of repairing it. It has no analogy, in my opinion, with any of the cases where the courts have held that an opinion cannot be given; but is analogous to the case where an action is brought to recover for an unsoundness, or defect in an article which has been warranted to be sound or perfect. And in such case it is undoubtedly correct to ask the witness the difference in value between the article, if it had been as warranted to be, and as it in fact was. (Nickley v. Thomas, 22 Barb. 655. Brill v. Flagler, 23 Wend. 354. Casey v. Greeman, 4 Hill, 625. Joy v. Hopkins, 5 Denio, 84.) Besides, the answer of the witness could not possibly injure the defendants. He had given items of expense *589necessary to the repair of the boat, amounting to more than the verdict, exclusive of the loss of time and expense of waiting for the repairs to be made; and that testimony was undisputed. And it is a well settled rule that a judgment will not be set aside, even on a bill of exceptions, for testimony erroneously admitted, when the court can see clearly that it has occasioned no injury to the objecting party. (Bort v. Smith, 5 Barb. 283, 285. Crary v. Sprague, 12 Wend. 41. Benjamin v. Smith, Id. 404.)
And it is quite clear that the return of the justice is not to he treated as a bill of exceptions. It partakes more of the nature of a case to set aside a verdict or report of referees. And, in such cases, the whole case is to he examined, and if the court can see that substantial justice has been done, notwithstanding the alleged error, it will not interfere. (Bort v. Smith, 5 Barb. 285. Spencer v. Saratoga and W. Railroad Co., 12 id. 383.)
There was no error in the refusal to nonsuit the plaintiff. The defendant may demur when it appears on the face of the complaint that there is a defect of parties. (Code, § 144.) When it does not appear upon the face of the complaint, the objection may be taken by answer. (Id. § 147.) And if the objection be not taken by demurrer or answer, the defendant shall be deemed to have waived the same. (Id. § 148.) And where, in .an action for a tortious injury to personal estate owned by joint tenants, one of the joint owners is not a party plaintiff, and the defendant omits to avail himself of the nonjoinder, in pleading, he will not he allowed on the trial to prove the interest of the owner, not joined in diminution of the amount to be recovered. (Zabriskie v. Smith, 3 Kern. 322.) And the rule must be the same in the case of copartners.-
The remaining question is whether the evidence was sufficient to support the verdict. The plaintiff was without fault; his boat was close to the heel-path, for the purpose of unloading, where the canal was wide enough for three *590boats to lie abreast, and at the place assigned by the superintendent for that purpose. The defendant was proceeding in the same direction with the raft, and while passing the raft saw the plaintiff’s boat, and saw the Rochester boat coming from the east, while some distance from his boat; and he mnst have known that if his boat kept on hé would meet the Rochester boat opposite to the raft, and opposite to or near the plaintiff’s boat. But one of the defendants, Albert Cone, testified that he kept on and did not slacken up his team until he was within about one hundred feet of the. plaintiff’s boat; at Which time it must have been apparent that he must come in collision with the Rochester boat, while it was opposite to the plaintiff’s’ boat and" opposite to the raft. He was negligent, then, in not stopping and thus avoiding the collision at the earliest moment when he had reason to apprehend that a. collision might' occur; and it is no answer to say that the Rochester boat was in fault, and contributed to the injury, for, as between them and the plaintiff, he could sue either of them who. contributed to his injury. But .the fault was on the part of the defendants. By -slacking up when they first discovered the other boats, the raft would have gone ahead of their boat, and room would have been made for the boats to pass. And, in addition to this, the canal regulations, section 50, declare that-“In all cases where two boats or floats going in opposite directions, shall approach each other in the vicinity of a raft, in such manner that they would, if both should continue their headway, meet by the side of such raft, the boat or float which shall be going in the same direction as the raft, shall stop until the boat or float going in the opposite direction shall pass such raft.” How, it is not enough that the defendants did not see the boat coming from the east when they turned out to pass the raft. It was their duty to see it, or to stop as soon as they-did see it; or, at all events, they had no right to attempt to pass the raft till they could, in fact, do so, without meet*591ing the other boat opposite to it. They were legally in the wrong, therefor, and are answerable for the consequences.
[Onondaga General Term, April 5, 1864.The judgment of the county court should be reversed, with costs of the appellant on this appeal, and the judgment rendered by the justice affirmed.
Morgan, Bacon and Foster, Justices.]