steps necessary for a location in the statutory order, although not until after the applicant for the patent had done everything required by law, would there be any justice in sustaining the adverse suit and awarding the property to the plaintiff therein on the ground that the applicant had not made any discovery until the day after his marking on the ground, and so the discovery did not precede the location?

These suggestions add strength to the concurring opinion of three leading commentators on mining law, the general trend of the rulings of the Department and decisions of the courts, to the effect that the order in which the several acts are done is not essential, except so far as one is dependent on another. Doubtless a locator does not acquire the right of exclusive possession unless he has made a valid location, and discovery is essential to its validity, but if all the acts prescribed by law are done, including a discovery, is it not sacrificing substance to form to hold that the order of those acts is essential to the creation of the right? It must be remembered that the discovery and the marking on the ground are not matters of record put in pais, and if disputed in an adverse suit or otherwise must be shown, as other like facts, by parol testimony. It must also be remembered that the certificate of location required by the Colorado statutes need not be verified. The one in this case was not. A locator might, if so disposed, place the date of discovery before it was in fact made, and at any time within three months prior to the filing of the certificate.

But it has been said that the question has been decided by this court adversely to these views, and Enterprise Mining Company v. Rico-Aspen Mining Company, 167 U. S. 108, and Calhoun Mining Company v. Ajax Mining Company, 182 U. S. 499, are cited. In the former case the question was as to when a vein discovered in a tunnel must be located, and in the opinion (p. 112) we said:

"In order to make a location there must be a discovery; at least, that is the general rule laid down in the statute. Sec

tion 2320 provides: 'But no location of a mining claim shall be made until the discovery of the vein or lode within the limits of the claim located.' The discovery in the tunnel is like a discovery on the surface. Until one is made there is no right to locate a claim in respect to the vein, and the time to determine where and how it shall be located arises only upon the discovery-whether such discovery be made on the surface or in the tunnel."

But that comes far short of meeting the question before us. It is undoubtedly true that discovery is the initial fact. The language of the statute makes that plain, and parties may not go on the public domain and acquire the right of possession by the mere performance of the acts prescribed for a location. But the question here is whether, if there be both a discovery and the performance of all the acts necessary to constitute a location, the order in which these things take place is essential to the right of exclusive possession which belongs to a valid location?

In the Ajax case the contest was between mining claims on the one hand and a mining claim and tunnel site on the other. All the mining claims had passed to patent. The plaintiff in error, who was defendant below, held the junior patent issued upon a later entry, and the entries of plaintiff's claims were made and the receiver's final receipts issued prior to the location of the tunnel site. In other words, the defendant, admitting that its right to a tunnel had not been established by a location at the time of the entries of plaintiff's claims, sought to invalidate them by proof that there had been no previous discovery of mineral. This was refused by the trial court, and we sustained the ruling, saying (p. 510):

"The patents were proof of the discovery and related back to the date of the locations of the claims. The patents could not be collaterally attacked. This has been decided so often that a citation of cases is unnecessary."

An entry, sustained by a patent, is conclusive evidence that at the time of the entry there had been a valid location and VOL. CXCVI-23

such valid location implies as one of its conditions a discovery, and the decision only went to the extent that this could not be challenged by one who at the time of the entry had made no location and therefore had acquired no tunnel right. There is nothing in this ruling to conflict with the views we have expressed.

It would seem, therefore, from this review of the authorities as well as from the foregoing considerations that, as between the Government and the locator, it is not a vital fact that there was a discovery of mineral before the commencement of any of the steps required to perfect a location, and that if at the time of the entry everything has been done which entitled the party to an entry, to wit, a discovery and a perfect location, the Government would not be justified in rejecting the application on the ground that the customary order of procedure had not been followed. In other words, the Government does not, by accepting the entry and confirming it by a patent, determine as to the order of proceedings prior to the entry, but only that all required by law have been taken.

If, therefore, the entry and patent do not of themselves necessarily determine the order of the prior proceedings, why may not any one who claims rights anterior to the entry and dependent upon that order show as a matter of fact what it was? One not a party to proceedings between the Government and the patentee is concluded by the action of the Government only so far as that action involves a determination. There is a determination by the fact of entry and patent that there was prior to the entry a discovery and a location. Having been so determined third parties may be concluded thereby.

But it may be said that when the time of a particular fact is concluded by an adjudication or when an opportunity is presented for such an adjudication and not availed of, the time as stated must be considered as settled; that when the plaintiff applied for its patent if there was any question to be made by the defendant of any statement of fact made in the location certificate, or other record, it should have been challenged by

an adverse suit. Failing to do so the fact must be considered to be settled as stated. Undoubtedly, if in an adverse suit the time of any particular matter is litigated, the judgment is conclusive, and if the date of discovery stated in the plaintiff's location certificate had been challenged in an appropriate action brought by the defendant and determined in favor of the plaintiff, there could be now no inquiry. So, when the owner of a lode claim makes application for a patent and the owner of another seeks to challenge the former's priority of right on account of the date of discovery, it is his duty to bring an adverse suit, and if he fails to do so that question will be as to him concluded. Such is the purpose and effect of the adverse proceedings.

Is the same rule also applicable to a tunnel site? This opens up the question of what are the rights and obligations of the owner of a tunnel? And here these facts must be borne in mind. The owner of a tunnel never receives a patent for it. There is no provision in the statute for one, and none is in fact ever issued. No discovery of mineral is essential to create a tunnel right or to maintain possession of it. A tunnel is only a means of exploration. As the surface is free and open to exploration, so is the subsurface. The citizen needs no permit to explore on the surface of government land for mineral. Neither does he have to get one for exploration beneath the surface for like purpose. Nothing is said in section 2323 as to what must be done to secure a tunnel right. That is left to the miners' customs or the state statutes, and the statutes of Colorado provide for a location and the filing of a certificate of location. When the tunnel right is secured the Federal statute prescribes its extent—a tunnel 3,000 feet in length and a right to appropriate the veins discovered in such tunnel to the same extent as if discovered from the surface.

If the tunnel right was vested before a discovery in the plaintiff's lode claim the defendant ought to have the benefit of it. The plaintiff's right does not antedate his discovery, at least it does not prevail over any then existing right. But, it

is said, the defendant did not adverse the plaintiff's application for a patent; that its omission so to do precludes it from now asserting a right prior to the date of discovery named in the certificate of location, just as a judgment in an adverse suit involving the question of date would have been conclusive. Is the owner of a tunnel who simply seeks to protect his tunnel and has as yet discovered no lode claim, bound to adverse an application for the patent of a lode claim, the lode of which was discovered on the surface? It is contended that the case of Enterprise Mining Company v. Rico-Aspen Mining Company, supra, decides this question. But in that case the line of the tunnel did not enter the ground of the lode claim but ran parallel with and distant from it some 500 feet, and we held that the mere possibility that in the line of the tunnel might be discovered a vein which extended through the ground of the distant lode claim did not necessitate adverse proceedings. Here the line of the tunnel runs directly through the ground of the plaintiff, and the question is distinctly presented whether, in order to protect the right to that tunnel, the defendant was called upon to adverse. Whatever might be the propriety or advantage of such action, the statute does not require it.

Sections 2325 and 2326 provide the manner of obtaining a patent and for adverse proceedings. The first commences: "A patent for any land claimed and located for valuable deposits may be obtained in the following manner." This, obviously, does not refer to easements or other rights, nor the acquisition of title to land generally, but only to land claimed and located for valuable deposits. Then, after prescribing certain proceedings, the statute adds, "if no adverse claim shall have been filed with the register. . . it shall be assumed that the applicant is entitled to a patent

and that no adverse claim exists." The next section commences, "Where an adverse claim is filed during the period of publication, it shall be upon oath of the person or persons making the same, and shall show the nature, boundaries, and