The defendant did not unconditionally accept the order in the plaintiff’s favor. He accepted it “to be paid out of the last payment.” These words are ambiguous, and, without some extrinsic, explanation, are not intelligible. It was decided at the former hearing of this case, that evidence of the contract with Walsh, and of the acts and conversation of the parties at the time the acceptance was signed, was competent to aid in the construction of the writing. Proctor v. Hartigan, 139 Mass. 554. The evidence put in by the defendant at the second trial, to which the plaintiffs excepted, was therefore admissible.
Upon all the evidence, the jury have found that the contract of the parties was that the sum named in the order should be paid out of the last payment to become due to Walsh under his written contract with the defendant. In other words, the acceptance was conditional, and bound the defendant to pay out of such last payment. It was admitted that Walsh abandoned his work, and broke his contract, so that the last payment contemplated by the contract never became due to him.
*467The meaning of the parties was, that the order should be paid out of the sum which should become due to Walsh as the last payment provided for by the contract.
It follows that the condition upon which the defendant was to be liable to pay the order to the plaintiffs has not happened, and that he is not liable in this suit. The instructions requested by the plaintiffs were rightly refused, and those given were appropriate and sufficient.
Exceptions overruled.