Field, C. J. and Norton, J. concurring.

This case was before us at the April Term, 1862, on appeal from a judgment in favor of the defendants. The judgment was reversed, and the cause remanded for a new trial, and the present appeal is from a judgment in favor of the plaintiff. The plaintiff is a mining corporation, and the facts, as elicited at the trial, are not materially different from those stated in our previous opinion.

The point in dispute is the location of a mining claim, and one of the errors assigned is, that the Court refused the following instruction: “ No location of a mining claim can be so extended as to amount to a monopoly, and in the absence of local regulations prescribing a limit, recourse must be had to general usage. If the quantity of ground included be unreasonable, the location will not be effectual for any purpose, and possession under it will only extend to the ground actually occupied. In other words, the extent of the occupancy will determine the extent of the claim, and whether the quantity be unreasonable or not, must depend upon the customs prevailing generally upon the subject.”

This instruction was taken literally from the opinion delivered by us when the case was here before ; and it is difficult for us to understand upon what ground the Court refused to give it. It is too late now to discuss the question of its correctness, for the matter has been adjudicated; and whatever doubts may exist in regard to the conclusion arrived at, it has become the law of the case. The counsel for the plaintiff contends that the point was not involved in the questions raised on the former appeal, and that so much of the language used as limits a location in the case put to the extent of the actual occupation, was mere obiter. It is true, perhaps, that an opinion upon the point was not essential to the decision of the case; but it "was important for the purposes of a new trial; and it *552 was in that view that we considered the matter and passed upon it. It was a matter necessarily involved in the issue to he tried, and the principle of res judicata, is undoubtedly applicable to its determination.

The judgment is reversed and the cause remanded for a new trial.