The appellant has abandoned all assigned grounds of demurrer except its position in reference to the last two sentences (b and c) in the written instrument which is the subject of the controversy. It is contended that these clauses make the plaintiff’s promise illusory; that the plaintiff reserved complete protection against total nonperformance on its part; and that it retained the privilege of refusing to make any shipment to the defendant unless it chose to extend credit upon its own terms. To these contentions the appellant seeks to apply the principle that where a contract consists only of mutual promises there must be mutuality of obligation, and that where performance is dependent upon the will of one party the purported agreement does not constitute a contract. We do not concur in this interpretation.
If a contract is susceptible of two constructions one of which will make it enforceable and the other unenforceable, the former construction will generally be preferred. Torrey v. Cannon, 171 N. C., 519; Edwards v. Ins. Co., 173 N. C., 614. And as between two possible constructions, one of which makes the instrument an executory contract and the other an option the latter will be rejected because by the other construction mutual rights are conferred upon the contracting parties. 4 Page on Contracts, see. 2050.
Mutuality of promises means that promises to be enforceable must each impose a legal liability upon the promisor. Each promise then becomes a consideration for the other. Want of mutuality is merely one form of want of consideration. But a single consideration may support several promises; it is not necessary that each promise have a separate consideration. Hence, a covenant which imposes obligations upon one party only may be enforceable if it is part of an entire contract which is supported by a sufficient consideration. 1 Page on Contracts, secs. 525, 565 et seq.j 1 Williston on Contracts, sec. 141.
The paper is not lacking in mutuality of consideration. Mutuality of promises is manifest. The plaintiff contracts to sell to the defendant 50,000 yards of army duck on certain terms, and the defendant contracts to accept the goods and to pay the price. The parties evidently did not contemplate a shipment of all the goods at one time or in one bulk. The specifications were to be furnished by 15 November, 1925, so that the goods might be shipped not later than 27 February, 1926. One shipment was made 30 December, 1925, and another 5 January, 1926. The words “any delivery” imply the possibility of more than one shipment. To meet this situation the defendant agreed that delay or defect in quality in a single delivery of the duck should not be cause for cancellation of the entire contract, or a cause of action for breach of the entire contract; but he did not contract against his right to bring *752suit for any loss caused by tbe plaintiff’s delay in making “tbe delivery in question,” or by any defect in tbe quality of tbe goods.
Tbis agreement is not a discharge of tbe plaintiff from liability for breach of bis contract; it is not a covenant not to sue. Nor is it a unilateral promise similar to that in Rankin v. Mitchem, 141 N. C., 277. There tbe contested claim was held to be unilateral because it was not intended to bind tbe defendant and did not purport to impose upon him any obligation; but here tbe obligation assumed by tbe defendant is only a part of an entire contract which is supported by a valuable consideration. Tbe contract does not, as we understand it, confer upon tbe plaintiff an unlimited right to determine tbe nature or extent of bis performance so as to make bis promise illusory. He is bound by tbe terms of bis contract and is liable in damages for its breach. Fortes v. Mill Co., 195 N. C., 51.
Tbe sentence relating to the extension of credit must be construed in connection with other parts of tbe contract. If, as we have said, tbe parties contemplated tbe probable delivery of tbe goods in installments, a stipulation that tbe seller should regulate or limit tbe amount of tbe unpaid installments would not avoid tbe contract or render it unenforceable ; and tbis, we apprehend, is as distinctly one of tbe purposes of tbe provision as a desire to guard against tbe possible intervening insolvency of tbe debtor. Slater Refining Corporation, 110 S. E. (Ga.), 759; Mendel v. Converse & Co., 118 S. E., (Ga.), 587, 879; Seed Co. v. Jennette Bros., 195 N. C., 173.
Tbe judgment of tbe Superior Court overruling tbe demurrer is
Affirmed.