lands, in fact mineral, would afford no protection to the railroad company in the event of the future discovery of precious metals therein. This is a mistake. After the Secretary of the Interior has decided that any particular lands are not mineral, and has issued a patent therefor, the title is not liable to be defeated by the subsequent discovery of minerals. The authorities upon this point are cited in Mr. Shields' original brief (pp. 46 to 60).

"The point is also covered by the case of Davis v. Weibbold, 139 U. S. 507, where a patent was issued for a town site, and minerals were subsequently discovered in the lands patented. But it was held that the title was not affected by such discovery, and that the provision of the town-site act (Rev. Stat., § 2392) that 'no title shall be acquired to any mine of gold, silver, cinnabar, or copper,' does not apply where the mines were discovered after a patent has been issued.

"Mr. Justice Field, delivering the opinion of the court, quotes with approval, at page 521, the following language of Judge Sawyer in Cowell v. Lammers [21 Fed. Rep. 200, 206]: 'There must be some point of time when the character of the land must be finally determined, and, for the interest of all concerned, there can be no better point to determine this question than at the time of issuing the patent.'

"And again, at page 523, he quotes with approval the following language of Mr. Justice Lamar, while Secretary of the Interior [5 L. D. 194]: 'The issue of said patent was a determination by the proper tribunal that the lands covered by the patent were granted to said company, and hence, under the proviso of said act, were not mineral at the date of the issuance of said patent.'

"And again, page 524: 'The grant or patent, when issued, would thus be held to carry with it the determination of the proper authorities that the land patented was not subject to the exception stated.'

"In Moore v. Smaw, 17 California, 199, it was decided, in the first opinion delivered by Mr. Justice Field as chief justice of the supreme court of California, that the patent of the United States passes title to minerals.

"Of course, if the railroad company knows at the time of receiving a patent that the lands covered by it are mineral, a case of fraud is presented which entitles the Secretary of the Interior to have the patent canceled, as was done in Morton v. Nebraska, 21 Wall. 660, and in The Western Pacific Railroad Company v. The United States, 108 U. S. 510. But, barring cases of fraud, the issuing of a patent by the Secretary of the Interior to the railroad company gives it an absolute title, not liable to be defeated by the subsequent discovery of minerals.

"Here, then, is a method of adjusting the company's grant according to the procedure contemplated by the act itself, which protects fully the interests of both the Government and the railroad, and which is in accordance with the practice which has always prevailed in the Department of the Interior." Citing Secretary Noble's decision in Central Pacific Railroad Co. v. Valentine, supra.

The court rejected the contention that the conditions existing at the date of definite location were decisive of whether the land was mineral or non-mineral, and held that the question remained an open one until the issue of a patent. In the latter connection the court referred to prior decisions respecting the power and duty of the Land Department, in issuing patents, to inquire and determine whether the lands are of the class prescribed, whether there are other claims to them, and whether the applicant is entitled to a transfer of the title; reaffirmed its ruling in Smelting Co. v. Kemp, 104 U. S. 636, 640, that a patent not only "operates to pass the title, but is in the nature of an official declaration by that branch of the Government to which the alienation of the public lands, under the law, is intrusted, that all the requirements preliminary VOL. CCXXXIV-44

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to its issue have been complied with;" and further said (pp. 328, 329):

"If the Land Department must decide what lands shall not be patented because reserved, sold, granted, or otherwise appropriated, or because not free from preëmption or other claims or rights at the time the line of the road is definitely fixed, it must also decide whether lands are excepted because they are mineral lands. If, as suggested by counsel, when the Secretary of the Interior has under consideration a list of lands to be patented to the Northern Pacific Railroad Company, it is shown that part of said lands contain minerals of gold and silver, discovered since the company's location of its road opposite thereto, he would not perform his duty, stated in Knight v. Land Association, 142 U. S. 161, 178, as the 'supervising agent of the government to do justice to all claimants and preserve the rights of the people of the United States,' by certifying the list until corrected in accordance with the discoveries made known to the department.

"There are undoubtedly many cases arising before the Land Department in the disposition of the public lands where it will be a matter of much difficulty on the part of its officers to ascertain with accuracy whether the lands to be disposed of are to be deemed mineral lands or agricultural lands, and in such cases the rule adopted that they will be considered mineral or agricultural as they are more valuable in the one class or the other, may be sound. The officers will be governed by the knowledge of the lands obtained at the time as to their real character. The determination of the fact by those officers that they are one or the other will be considered as conclusive."

And then, after quoting approvingly what we have already extracted from Secretary Noble's decision in Central Pacific Railroad Co. v. Valentine, supra, it was added (p. 330): "It is true that the patent has been issued

in many instances without the investigation and consideration which the public interest requires; but if that has been done without fraud, though unadvisedly by officers of the Government charged with the duty of supervising and attending to the preparation and issue of such patents, the consequence must be borne by the Government until by further legislation a stricter regard to their duties in that respect can be enforced upon them."

Of the decision in that case it was concisely said in Shaw v. Kellogg, 170 U. S. 312, 339: "It is true there was a division of opinion, but that division was only as to the time at which and the means by which the non-mineral character of the land was settled. The minority were of the opinion that the question was settled at the time of the filing of the map of definite location. The majority, relying on the language in the original act of 1864 making the grant, and also on the joint resolution of January 30, 1865, which expressly declared that such grant should not be 'construed as to embrace mineral lands, which in all cases shall be and are reserved exclusively to the United States, held that the question of mineral or non-mineral was open to consideration up to the time of issuing a patent. But there was no division of opinion as to the question that when the legal title did pass-and it passed unquestionably by the patent-it passed free from the contingency of future discovery of minerals."

The exclusion of mineral lands is not confined to railroad land grants, but appears in the homestead, desertland, timber and stone, and other public-land laws, and the settled course of decision in respect of all of them has been that the character of the land is a question for the Land Department, the same as are the qualifications of the applicant and his performance of the acts upon which the right to receive the title depends, and that when a patent issues it is to be taken, upon a collateral attack, as affording conclusive evidence of the non-mineral character of

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the land and of the regularity of the acts and proceedings resulting in its issue, and, upon a direct attack, as affording such presumptive evidence thereof as to require plain and convincing proof to overcome it. Smelting Co. v. Kemp, 104 U. S. 636, 641; Steel v. Smelting Co., 106 U. S. 447; Maxwell Land Grant Case, 121 U. S. 325, 379–381; Heath v. Wallace, 138 U. S. 573, 585; Noble v. Union River Logging Railroad, 147 U. S. 165, 174; Burfenning v. Chicago, &c. Railway Co., 163 U. S. 321, 323. In this respect no distinction is recognized between patents issued under railroad land grants and those issued under other laws; nor is there any reason for such a distinction.

Of course, if the land officers are induced by false proofs to issue a patent for mineral lands under a non-mineralland law, or if they issue such a patent fraudulently or through a mere inadvertence, a bill in equity, on the part of the Government, will lie to annul the patent and regain the title, or a mineral claimant who then had acquired such rights in the land as to entitle him to protection may maintain a bill to have the patentee declared a trustee for him; but such a patent is merely voidable, not void, and cannot be successfully attacked by strangers who had no interest in the land at the time the patent was issued and were not prejudiced by it. Colorado Coal & Iron Co. v. United States, 123 U. S. 307, 313; Diamond Coal Co. v. United States, 233 U. S. 236, 239; Germania Iron Co. v. United States, 165 U. S. 379; Duluth & Iron Range Railroad Co. v. Roy, 173 U. S. 587, 590; Hoofnagle v. Anderson, 7 Wheat. 212, 214-5. In the last case this court said, speaking through Chief Justice Marshall: "It is not doubted that a patent appropriates land. Any defects in the preliminary steps, which are required by law, are cured by the patent. It is a title from its date, and has always been held conclusive against all those whose rights did not commence previous to its emanation.

If the patent has been issued irregularly, the Government