may, so far as its known character is concerned, be nonmineral. Exploitation after the state has acquired its title may develop its mineral character. The legislature of the state may impress upon its conveyance to grantees limitations and reservations in the light of which all state patents must be construed.1 It is impossible to state any general rule as to the operative force of such instruments, as legislation in this regard may not be, and in fact is not, the same in all the states. In the absence of any legislation imposing limitations upon the title so conveyed, it may be assumed where the general government has approved and certified to the state, lands in satisfaction of its indemnity or floating grants, that such certification, followed by a state patent, would make the title in the vendee impervious to collateral attack.2 In the case of sixteenth and thirty-sixth sections, we have heretofore observed that there is no preliminary investigation by the land department as to the character of the land. Neither the law nor regulations of the department prescribe any procedure for a determination of the question as a condition precedent to the vesting of title in the state. As there is neither certification nor patent for these sections emanating from the general government, there is nothing upon which to base a conclusive presumption that the lands at the date of the survey were of any particular character. For many years it has been the custom in California, and perhaps elsewhere, for the state land officers, prior to disposing of the lands within sixteenth and thirtysixth sections, to obtain from the register of the local United States land office a certificate showing the status 1 Stanley v. Mineral Union (Nev.), 63 Pac. 59, 60. McCormick v. Hayes, 159 U. S. 332, 348, 16 Sup. Ct. Rep. 37. of these sections as disclosed in the tract-books,1-that is, as to whether it appears from such books that there. are pre-emption or homestead filings covering these sections, or other facts which might impair the title of the state. If there appear on these books no notations showing the existence of any impediments, the register has, at the request of the state, so certified, and noted the fact of certification in the tract-books. There is absolutely no authority for this so-called "certificate." The action of the register is not supplemented by any action on the part of the commissioner or secretary of the interior. The certificate does not purport to deal with the character of the land, the only evidence as to that fact being the United States surveyor-general's return, which, as heretofore pointed out, is not entitled to serious weight. Registers of the land office have no powers except such as are defined in the acts of congress and in departmental regulations made in pursuance of law,2 and the power to give such certificates is not given either expressly or by implication in either the acts of congress or departmental regulations. The attention of the secretary of the interior has (we think for the first time) been recently called to this practice of issuing certificates from the register's office, through a report made to the commissioner of the general land office by one of the registers, which report was as follows: "I find noted upon the tract-books these words (with "regard to a certain section 16) 'Certified to the state 'per J. W. Garden, register, Oct. 8, 1885.' Our tract"books are filled with notations of this kind or similar "notations to sections sixteen and thirty-six, and I pre"sume that it was the practice of former registers, as it "is now, to certify to the state, upon inquiry by the state 66 surveyor-general, the status of the lands in sections "sixteen and thirty-six as shown by the records." With reference to this procedure, the secretary says: 66 "It is apparent by this statement of the register that "neither his predecessors nor he has comprehended the "nature of their duties respecting these school sections. "No such notations as is here indicated should have "been issued. The character of school sections in Cali"fornia as to whether mineral or non-mineral is not to "be wholly determined by the surveyor-general's return, nor indeed is his return considered as a very "high or persuasive evidence of the character of the "lands when it is once drawn in question.. It is "also possible that lands in a school section might be "excepted from a grant to a state because of other "things than their mineral character, which would not "necessarily be shown upon the records of the local "office. "While it is competent and proper for the local "officers, in response to legitimate inquiries, to give "such information as is shown by the records of their "office,-as, for instance, whether a given section six"teen has been returned as mineral or non-mineral, or "whether any portion thereof is or is not included in a "homestead or other entry,-it is not competent or proper that these officers should also undertake to "state in a manner which may be erroneously accepted "as a certification or authorized statement that the sec"tion has or has not passed to the state."1 The supreme court of California seems to have treated this class of certificates issued by the register as possessing the same legal effect as a certification by the commissioner of the general land office approving lieu or indemnity selections or selections in satisfaction of floating grants, and has said that such certification fol Instructions, 31 L. D. 212. lowed by the issuance of a state patent renders the title so evidenced immune from collateral attack.1 A previous decision by the same court sanctioned a collateral attack on a state patent by a mineral claimant, and upheld the title to the mining claim upon the findings of the trial court, that at the date of the survey the land was known to be mineral.2 It is manifest that either the court in its last expression has given to the register's certificate unwarranted legal value or the secretary of the interior has without legal justification inhibited the practice of issuing such certificates. With all possible deference to the supreme court of California, the logic of the situation would seem to be with the secretary of the interior. A state patent cannot transmit a title which the state did not receive. If the lands are known to be mineral at the date of the survey, the title does not pass to the state." One occupying the status of a bona fide mining locator at the date of survey, not being in privity with the state, could under the later decision of the supreme court of California be deprived of his "day in court" by the issuance of a state patent. We do not think the question of the known character of the land within a sixteenth or thirty-sixth section, is foreclosed by the issuance of such patent. The question may be investigated at any time, either by the courts, in the absence of a contest pending before the land department, or by that tribunal, at the instigation of an applicant for a mineral patent, due notice of such application being given to the state or its grantee.* 1 Saunders v. La Purisima G. M. Co., 125 Cal. 159, 57 Pac. 656. 'Hermocilla v. Hubbell, 89 Cal. 5, 26 Pac. 611. Ivanhoe M. Co. v. Keystone M. Co., 102 U. S. 167. Fleetwood Lode, 12 L. D. 604; Boulder and Buffalo M. Co., 7 L. D. 54. 2145. Conclusions. -From the foregoing exposition of the law, we deduce the following conclusions: (1) That lands embraced within sixteenth or thirtysixth sections, known to be mineral in character at the date of the final approval of the survey, do not pass to the state, but remain a part of the public mineral domain, subject to exploration and purchase, the same as other public mineral lands. (2) The state may not select as lieu lands, or lands in satisfaction of its floating grants, any tract whose mineral character is known or established prior to the final approval of the selection and listing to the state. (3) The approval by the commissioner of the land office of a selection by a state of lands under an indemnity or other floating grant is in the absence of fraud a conclusive adjudication of the character of such lands. Such approval and certification have the effect of a patent. (4) Where sixteenth and thirty-sixth sections are returned by the surveyor as mineral, and the state accepts this return and selects other lands in lieu thereof, both the state and general government are estopped from threafter asserting that the lands are non-mineral. (5) Where such sections are returned as mineral, and the state does not accept the return as establishing the character of the land, it has a right to its "day in court" for the purpose of impeaching the return. Where it desires to select lands, either in lieu of sixteenth and thirty-sixth sections or under its floating grants, which lands are returned by the surveyor-general as mineral, it has a right to "prove the mineral off," and, if successful, to have other lands listed to it. (6) Whether or not a given tract is of a known mineral character at the time the grant or selection would |