Mr. Justice Bean
delivered the opinion of the court.
1. The first three assignments of error challenge the sufficiency of the complaint on the ground that the contract sued on is entire, and not severable, and therefore no recovery can be had without allegation and proof of full performance. The contract provides for the sale by the plaintiffs to the defendants of the entire mill cut of the former for the year 1903, but it is stipulated that all lumber delivered during one month shall be paid for on the 10th of the following month. Delivery, acceptance, and payment were therefore to take place by installments extending through the season, and in such case a vendor may maintain an action to recover for any installment when it becomes due, without pleading or proving full performance on his part: Clark, Contracts, § 275, p. 657; Tenny v. Mulvaney, 8 Or. 129; Coos Bay R. Co. v. Nosler, 30 Or. 547 (48 Pac. 361); Coos Bay R. Co. v. Dixon, 30 Or. 584 (48 Pac. 360); Oliver v. Oregon Sugar Co. 42 Or. 276 (70 Pac. 902).
2. The fourth, fifth, eighth, and ninth alleged errors relate to the admission of testimony to show the meaning of the words “merchantable lumber, mill run,” used in the contract, and the character of lumber properly included therein. The argument seems to be that by the contract the plaintiffs were to furnish the defendants, “as jobbers and shippers to a foreign market,” their mill cut for the season of 1903, to he “manufactured upon cutting orders of the defendants and for the express purposes of their trade”; and therefore it was error to admit evidence *46to show what would be “merchantable lumber, mill run,” according to the local meaning of these words as understood in the business. The contract does not provide that the lumber is to be furnished defendants “as jobbers and shippers to a foreign market,”'nor that it shall be suitable for their trade, but simply that it shall be “merchantable lumber, mill run.” It is true, there is an allegation in the answer that plaintiffs knew at the time the contract was made that the lumber was intended for a special purpose, and made the contract with reference thereto. This averment is denied by the plaintiffs. It was competent, therefore, from their standpoint, to show the meaning of the terms “merchantable lumber, mill run,” as used in the vicinity where the contract was made. These words are. not in common use,'and have no settled judicial meaning. They are peculiar to the lumber trade or business, and, as the evidence tended to show, have a special meaning, and are well understood by persons engaged in such business. The testimony was therefore important and necessary, in order to enable the court to construe the contract, and the jury to render a proper verdict: 2 Wharton, Evidence (2 ed.), § 962; Corneil v. New Era Lum. Co. 71 Mich. 350 (39 N. W. 7); Jones v. Anderson, 82 Ala. 302 (2 South. 911). *
3. The sixth and seventh points refer to the refusal of the court to give certain instructions requested. The first is that, if the plaintiffs knew at the time the contract was made that the lumber to be furnished by them was intended for a certain purpose, it must have been suitable for such purpose, to be merchantable under the contract, and that, before the monthly settlement between the parties would be binding on the defendants as an acceptance of the lumber previously delivered, it must appear that such settlements were made with full knowledge of the facts. Both of these instructions were given by the court in practically the same language as requested, and we are unable to understand why their refusal should be assigned as error.
The remaining assignments of error were to the giving of certain instructions by the trial court. No objections to any of *47these instructions are suggested in the brief, and, from a reading of them, we are not able to discover any. Judgment affirmed.
Affirmed.