The complaint, after setting forth the lease in- extenso, alleges • that the clause therein contained relating to the supply of steam by the lessors, should be reformed by eliminating therefrom the words and figure “ four (4) horse,”' on the ground of mutual mistake and inadvertence of the plaintiff and"the defendants. It will be noticed, therefore, that there is no claim of fraud or deceit practiced by the defendants in inducing the execution of the lease^ but the question presented is as to whether the words “four (4) horse” power were inserted in the lease by mutual mistake. It ;will be further noticed that in the lease itself tlie covenant of the defendants is in the alternative, and under it the defendants agreed to-furnish “four (4) horse steam power or (60) sixty lbs. pressure.”
A review of the testimony will show- beyond cavil that in the negotiations which led up to the making of the léase and the insertion of this alternative covenant, it was thought and understood by the plaintiff and the broker who represented the defendants, that its terms were equivalent; and that it was only after more than a year when the defendants failed and -neglected, owing to the inability of their- -boiler, to then supply sixty pounds pressure, that attention was called to the fact that four horse power was not the equivalent .of sixty pounds pressure.
Upon the trial it was conceded that the two terms are entirely different in- meaning and application, “ four (4) horse steam power ” expressing quantity of steam, and “ sixty lbs. pressure ” the quality or pressure at which the steam is delivered. It was also established that in the defendants’ business what-was needed-Was steam through a one- and one-half inch pipe supplied'as needed during-the day at sixty pounds pressure.
The respondents (state the rule correctly, that'in order to justify the interposition of a court of equity in undertaking to reform a contract in Writing, the evidence should be clear. and convincing such as to leave no reasonable doubt as to the mutual mistake. The burden of producing satisfactory evidence rested-upon the plaintiff, and, in our opinion,- he has successfully sustained it, *415because it is seldom, if ever, that a case is presented wherein a mutual mistake has been so satisfactorily proved.
According to the plaintiff the words “ four (4) horse steam power ” were in the lease when first presented to him by the broker, and he then objected to them upon the ground that he did not know what these words, meant, and that what he needed and must have in the conduct of his business was sixty pounds' pressure of steam, and he insisted that the covenant to supply that amount of pressure should be inserted in the lease, which was done, and the other words were allowed to remain upon the assurance of the broker that one horse . power equaled fifteen pounds pressure and four horse power would be equivalent to sixty pounds pressure. It was upon this representation as to the terms being equivalent, which was undoubtedly relied upon by the plaintiff, and. which we must assume that the broker himself believed, that the words “four (4) horse steam power” were allowed to remain in the lease.
We do not, therefore, agree in the contention of the respondents that this evidence fails to show that there was any mistake on behalf of. the defendants in adopting the phraseology appearing in the lease relating to the supply of steam. The defendants were represented in the transaction by their broker, and as the agreement was arranged between the plaintiff and the broker representing the defendants, the latter’s acts and understanding of the meaning of the language used and its purpose are binding upon the defendants.
The- broker’s testimony shows that he did not know the difference between four horse power and sixty pounds pressure, and all the surrounding circumstances support the plaintiff’s version that he refused to sign the lease with the words “ four (4) horse steam power ” in it until there was also inserted the covenant as to the sixty pounds pressure. "Unless the parties understood these terms to be equivalent,. it is difficult to see any reason for inserting them in the lease since they differ in meaning and application. What the plaintiff needed was sufficient steam for his business of sponging cloth, and this required a sixty pounds pressure of steam. Moreover, one of the defendants’ witnesses, who rented steam, testified that with ' respect to spongers they always contracted to furnish a given pressure through a given pipe, because it was the only way to *416determine the amount to be supplied, and that fifty pounds was the ordinary requirement.
The lease itself states that the sponging business was to be carried on, and the uncontradicted testimony is that this could not be done with less than sixty pounds pressure. But the most significant fact as indicative of the construction which the parties themselves placed upon the covenant in the lease is that for more than a year, though it was attended with trouble and expense, the defendants actually furnished the sixty pounds pressure, the engineer’s testimony being that every morning he saw to it that sixty pounds was ready for the spongers when they arrived for work, and that he worked the boiler hard to keep up that pressure. It was only after the boiler had been used up and commenced to leak and was unable to furnish sixty pounds pressure that the defendants fell back upon the alternative provision in the lease of four horse power, and insisted that in furnishing that amount of steam they were complying with their lease, regardless of the amount of pressure.
It has been many times held that the practical construction put upon a contract by the parties to it is sometimes almost conclusive as' to its meaning (Nicoll v. Sands, 131 N. Y. 24), and that there is no surer way to find out what the parties mean than to see whát they have done. (Insurance Company v. Dutcher, 95 U. S. 273.)
The entire evidence, including the nature of the plaintiff’s business, the custom in furnishing steam for that business, the way in which the lease was made and the conduct of the defendants in supplying for over a year the pressure needed, seems to us to point with unerring certainty to the fact that the words “ four (4) horse steam power ” were inserted in the lease as the result of a mutual mistake and that the plaintiff was entitled to have -the lease reformed by striking out therefrom those words.
The question of damages, if any, to which the plaintiff would' be entitled is not before us upon this appeal, the judgment having been for the defendants. The judgment accordingly should be reversed and a new trial ordered, with costs to the appellant to abide the event.
Patterson, Ingraham, Hatch and Laughlin, JJ., concurred.
Judgment reversed, new trial ordered, costs to appellant to abide event.