Mr. Chief Justice Murray concurred.
1. Where the entire performance of a special contract has been prevented by one of the parties, or where its terms have been afterwards varied by the agreement of both parties, the action for the amount due for work and labor should be in the form of indebitatis assumpsit, and not upon the contract. In such ease the contract may be introduced in evidence by either party as an admission of the standard of value, or as proof of any other fact necessary to the recovery, and should be allowed . to go to the jury whenever it can aid them in attaining a sound conclusion.
2. There was enough evidence on the part of the plaintiff to be submitted to the jury, and the Court below was correct in refusing the non-suit.
3. The Court correctly ruled out the portion of BushnelPs testimony which was excepted to because he was not a mechanic, and not such an expert as to make evidence of his opinions about the masonry of the building.
4. The question to Carlisle might have been properly allowed, but its refusal has done no harm. It was asked upon the theory that the work *112of plaintiff was unskillfully done. The jury have found against this theory altogether, and therefore the error, if any, has been cured.
5. There was no sufficient predicate for the admission of Ralston’s testimony as to the lost receipts. He did not know in whose hand the receipts were written, and could, therefore, give them no verity. His evidence was properly excluded.
6. Ordinarily, as a.general rale, Courts are to give construction to written contracts, but this rule is frequently departed from, where the contract relates to the mechanic or scientific arts. In such cases it is common and prudent to admit the opinions of experts to explain the contract, and where the evidence otherwise tends to limit or enlarge the apparent meaning of the words used, the opinions of witnesses, who are in the habit of making and executing such contracts, are almost indispensable. Here the dispute was about the roof. It seems that the roof was put in proper order for tinning; that the defendant received the key and accepted the building, but refused to pay the balance due for the work, upon the single ground that the iron blinds and shutters Were not put up, which, by a special provision in the contract, was only to be done upon their arrival from New York; that immediately after-wards defendant had a tin roof put on.
This state of facts alone might be sufficient to exclude the idea that the plaintiffs were to put on a metallic roof by the terms of thé contract. It was, therefore, proper, ,in aid of this, that the witness was asked his opinion as to whether the expressions and terms used, disclosed a requisition upon the plaintiff to put a roof upon the house. His opinion was the common understanding of a mechanic, as to a subject of dispute, which the contract did not define, and which, aside from his opinion, and resting upon the contraet, with the other evidence, if left to a jury, as it properly might be, may have resulted in a conclusion either way. But, if the consideration of this point be put solely on the ground that it was the duty of the Court to construe the contract, then I am of opinion that, where a contract to build a house contains a specific description of every part, with one exception, stipulating for the manner, size, measurement and material of each, with great particularity, it must be held that the exception was the result of design, and did not enter into the contract of the parties.
The last objection to be noticed is the remark of the judge who tried the case, that, “if the jury differ in opinion as to what the witness did say, they were compelled to take the recollection of the Court.” The point of testimony to which this remark was applied, was as to the time a witness swore that he, as tenant of the defendant, moved into the house. I have searched the record carefully, and I cannot perceive that there was any relevancy in the testimony. As to the time of .the delivery and acceptance of the house, or the time it was first occupied, there seems to have been no contest, nor does the defence set up that it was not completed in time. On the contrary, the action is not on the contract, but for work and labor, and the defence is that the contract was not completed, but that the building was abandoned by the plaintiff *113in an unfinished state, before the time stipulated for its completion had elapsed. It could, therefore, have made no difference as to what time the tenant moved in. The damage of defendant, if any, must have commenced anteriorly, according to his own averments. If, therefore, any admeasurement of time could have been properly considered, in ascertaining the defendant’s damage, he would have introduced some evidence on that point. There is none in the record, and the single point of time ascribed by the Court, as a part of the declaration of a witness, who. swears that he moved into the house when it was unfinished, could have had no influence whatever.
There is no substantial error in the record, and the judgment is affirmed.