(after stating the facts). Counsel for appellant assign as error the action of the court in giving the following instruction: “IV. Defendant denies that he did in fact cut any timber on the south half of the south half, but says his operations were confined exclusively to the north half of the south half, and he says further that, even though any trees were cut on the said so-uth half of the south half, they were cut under the following circumstances: That the line between the said south half and the north half was undetermined, and was not known accurately to either himself or the plaintiff, and that to adjust any difference as to the true location of the line they established it by agreement fairly made and free from fraud, and that he cut no timber on the said south half as bounded by said established line. If you find the facts so to be, your verdict will be for the defendant.”
*513The instruction was erroneous, and should not have been given.
To sustain their contention, counsel for appellant rely upon the case of Schraeder Mining & Manufacturing Co. v. Packer, 129 U. S. 688, in- which the court hold: “A consent by coterminous proprietors of real estate to mark a boundary line supposed to run according to the marking between undisputed tracts, given by both in ignorance of the real facts and of the existence of a conflict, does not estop either from claiming his rights when the mistake is discovered; nor can it be construed as a license from the one party to the other, to cut timber on the disputed tract up to the mistaken boundary line.”
The evidence in the case at bar shows that 'appellant and appellee agreed upon a boundary line under the belief that it was the true line, when in fact it was not, .and that immediately the timber was cut and removed from the land. In short, it was an erroneous line agreed upon by mistake. In such cases the agreement is not binding, but may be set aside by either party when the mistake is discovered, unless there is some element of estoppel which prevents him. 4 Am. & Eng. Enc. Raw (2 ed.), 862.
It is only where the true line is unknown, or is difficult of ascertainment, and the parties establish the line to settle a disputed and vexatious question as to the boundary line between them, that the agreement is binding. In such cases the mutual concessions between the parties is a sufficient consideration for the agreement. In the present case the boundary line was not incapable of ascertainment. The parties agreed to the line under the mistaken belief that it was the true line.
The measure of damages in cases like this, where the property has been cut by an innocent trespasser and delivery can not be had, is the value of the property in its converted form, less the labor expended on it, provided such expense does not exceed the increase in value. Eaton v. Langley, 65 Ark. 448; Nashville Lumber Co. v. Barefield, 93 Ark. 353.
Counsel for appellant also insists that the court erred in not giving the folowing instruction: “You are instructed that, as to the alleged settlement and establishment of the line, the burden of proof is upon the defendant.” The court did not *514err in refusing this instruction; for, while the burden was on the defendant (appellee) to show payment, as declared in Hays v. Dickey, 67 Ark. 169, and cases cited, the burden was not on him to prove the “establishment of the line.” Under the well-settled rules of the court, appellant could not complain of the action of the court in refusing an instruction which was in part incorrect.
For the error in giving instruction No. 4 as indicated in the opinion, the judgment will be reversed, and the cause remanded for a new trial.