¶1By the Court,
¶2The plaintiff had no interest in the policy of insurance effected by the defendant. It is well settled in this state that a part owner may insure his individual interest without specifying that interest; it is sufficient if he has an insurable interest to the amount in question. 1 Caines, 284. 2 id. 203. If, indeed, it clearly appears that the owner who effected insurance did it on joint account, and the language of the policy is for account of whom it may concern, or of the owners, then every person having an interest may claim the benefit of the policy, but no one can recover for more than the interest which he proves. The amount insured in this case is the precise value, or nearly so, of the defendant’s interest in the brig, at the same rate at which he sold one sixth to the plaintiff The policy contains no words importing any interest in any other but the defendant; the plaintiff had given the defendant no orders to insure; and the declarations of the defendant that he originally intended the insurance for both, were coupled with a condition, provid*547ed the plaintiff was also interested in the cargo. Taking all the expressions of the defendant together, it seems to me they do not prove an insurance by him for the plaintiff’s benefit, unless the plaintiff was also concerned in the carsto : and litis 1 ° ’ the plaintiff declined. I am of opinion, therefore, that (he evidence offered did not justify a verdict in favor of the plaintiff The judge therefore decided correctly.
¶3The judge was also correct in excluding paroi evidence of the understanding of merchants as to (he construction and meaning of the policy. It is a good general principle that written agreements ought to be expounded by themselves. “ I know no rule heller established,” said Kent, justice, in N. Y. Ins. Co. v. Thomas, 3 Johns. C. 4, “ than that paroi evidence shall not be admitted to disannul or substantially vary or extend a written contract.”
¶4The judge was correct on both points, and the motion to set aside the nonsuit should be denied.