The question here presented is, not as to the competency of John S. Bates to effect an insurance for the benefit of all his associates, who were interested in the property which was the subject of the insurance, but whether, upon the face of this policy, and the terms of this contract of insurance, the legal effect is not to restrict the insurance to the sole interest of Bates. It may at once be conceded, that it was competent for Bates to effect such insurance on the entire interest of all concerned, if either previously authorized by the co-owners, or if they elected to ratify his act, even after the loss of the property. Finney v. Fairhaven Ins. Co. 5 Met. 192. But the appropriate form of the policy in such cases is, “ for himself and other owners,” or “ for whom it may concern,” or other words indicating that the insurance is to embrace an interest beyond that of the party in whose name the policy is issued. Such words, or equivalent ones, being introduced into the policy, the rules of law then authorize extrinsic evidence as to the persons who are parties in interest, and who may enforce their claims upon such policy, though not particularly named therein.

But the real question here is, whether a policy, made in the name of a particular person, who is the owner of a small proportion in interest of the property insured, without any words indicating an intention to insure beyond his own interest, can be made effectual to cover the interest of others, upon parol proof that the application for insurance was for such others, as well as for the party named, and that this was well known to *351the insurers, and that it was the intention and understanding of all the parties, that the policy was to cover the interest of all the owners. The general rule excluding parol evidence, when oflinrd tu contradict or vary the terms of a written contract, seems to forbid it. When the parties have put their agreement into writing, and the terms of it are plain and direct, leaving no uncertainty as to the nature of it, we must treat it as the whole engagement of the parties; and this excludes all parol evidence of conversations, or declarations of the intentions of the parties, tending to show another and different contract. Stackpole v. Arnold, 11 Mass. 31. Greenl. on Ev. § 275. This principle, we apprehend, applies as well to contracts of insurance as to other agreements. Such seems to be the doctrine of the adjudicated cases. Thus in Pearson v. Lord, 6 Mass. 84, Sewall, J. in delivering the opinion of the court, says, “ the instrument itself is regarded as the best, and, for this purpose, must be understood to be the only evidence of the contract. No case can, I believe, be imagined, where the maxim, expressio unius est exclusio alterius, applies more emphatically than in the naming of the party assured in a policy of insurance.” In Graves v. Boston Marine Ins. Co. 2 Cranch, 419, it was held that,a policy m the name of one part owner, with the words added, “ as property may appear,” without the clause stating the insurance to be for the benefit of all concerned, does not cover the interest of another joint owner; the words, “as property may appear,” being considered as applicable to the property of the one in whose name the policy issued. Marshall, C. J. says, “ the contract ought to have been so expressed as to show that the interest of some other than Graves was secured, if such was to be the effect of the instrument. A policy, though construed liberally, is still'a special contract; and under no rule for proceedings on a special contract, could the interest of copartnership be given in evidence on an averment of individual interest, or the averment of the interest of a company be supported by a special contract relating in its terms to the interest of an individual.” See also Murray v. Columbian Ins. Co. 11 Johns. 302. Turner v. Burrows, 5 Wend. 541. Finney v. Warren Ins. Ce, 1 Met. 18.

*352The only case referred to by the plaintiff which seems, in any degree, to conflict with this view of the subject, is that of De Vignier v. Swanson, cited in a note to Bell v. Gilson, 1 Bos. & Pul. 346, wher.e it seems to have been held that a policy of insurance, in the name of certain persons who procured it as agents, although they were not described as agents in the policy, was good and valid for the persons for whom it was effected. The question there raised, however, was merely, whether the form of the policy was in accordance with the provisions of the St. of 28 Geo. III. c. 56, requiring the names of the consignors or consignees of the property to be insured, or the names of the persons residing in Great Britain who shall receive the order or effect such policy, or the persons who shall give the order or direction to the agent employed to effect such policy, to be inserted in such policy; and it was held to be a sufficient compliance with the statute to insert the names of the agents, without stating them to be agents.

The court are of opinion that the evidence proposed in the case at bar was incompetent, and that the verdict for the defendants was properly ordered. The plaintiff has, however, leave to amend by striking out the names of all the plaintiffs except John S. Bates, who will be entitled to recover, to the extent of his interest in the property insured.