Erhardt v. Boaro, 113 U.S. 527 (1885), was an action for the possession of a mining claim in Pioneer mining district, in the County of Dolores, and State of Colorado. The claim was designated by the plaintiff as "The Hawk Lode" mining claim, and by the defendants as "The Johnny Bull Lode" mining claim. It contains two counts. The first alleges that the right of possession of the claim by the plaintiff on June 17, 1880, is by virtue of its location pursuant to the laws of the United States and of the state, and the local rules and customs of miners in the district, and by virtue of priority of possession, the wrongful entry upon the premises by the defendants on the thirtieth of that month, their outing the plaintiff therefrom, and unlawfully withholding the possession from him, to his damage of $50,000. The second count, in addition to the citizenship of the parties, the possession of the claim by the plaintiff, and the subsequent wrongful entry of the defendants, and their ousting him, alleges that the defendants worked and mined in the claim, and dug out and removed from it large quantities of gold and silver bearing ore of the value of $50,000, to the damage of the plaintiff in that amount. The plaintiff therefore prays judgment for the possession of the mining premises and for damages of $100,000.
 The answer of the defendants contains a specific denial of the several allegations of the complaint, and as to that it avers their want of information and demands proof. And it sets up the discovery of the claim in controversy on June 30, 1880, by the defendants Boaro and Hull, to which they gave the designation of "The Johnny Bull Lode," and its definite location and record within ninety days thereafter, and their subsequent relocation of the claim September 8, 1880, to avoid a conflict with an adjoining claim. They pray therefore that they may be decreed its possession and ownership in accordance with their rights.
 In the trial, the plaintiff produced evidence showing that on June 17, 1880, one Thomas Carroll, a citizen of the United States, while searching, on behalf of himself and the plaintiff, also a citizen, for valuable deposits of mineral, discovered, on vacant unoccupied land of the public domain of the United States in the Pioneer mining district mentioned, the outcrop of a vein or lode of quartz and other rock bearing gold and silver in valuable and paying quantities; that by an agreement between him and the plaintiff, pursuant to which the explorations were prosecuted, all lodes and veins discovered by him were to be located, one-fifth in his name and four-fifths in the name of the plaintiff; that on the day of his discovery, Carroll designated the vein or lode as the "Hawk Lode," and posted at the point of discovery a plain sign, or notice in writing, as follows:
 The evidence also showed that Boaro and Hull entered upon the premises on or about July 21, 1880, and remained thereafter continuously in possession; that threats of violence to the plaintiff and Carroll, if they should enter upon the premises or attempt to take possession of them, were communicated to Carroll as having been made by Boaro early in August following; that in consequence of such threats and the possession held by Boaro, Carroll was prevented from resuming work upon and completing the discovery shaft, and from entering upon any other part of the lode or vein and performing the acts of location required by law within the time limited. The evidence also tended to show that within ninety days from the discovery of the lode by Carroll, one French, on behalf of the plaintiff and Carroll, secretly caused the boundaries of the claim to be marked by six substantial posts, so as to include the place of discovery and the premises in controversy, and filed in the office of the recorder of the county a location certificate setting forth the name of the lode, the date of the location, the names of the plaintiff and Carroll as locators, and the course of the lode or vein, and giving such a description of the claim, with reference to natural objects and permanent landmarks, as would suffice to identify the same with reasonable certainty.
 The evidence offered by the defendants rebutted that of the plaintiff, and showed that on June 30, 1880, when Boaro entered upon the ground in controversy, he found nothing on the surface to indicate a vein or lode, or that any excavation had been made or stake erected, as alleged by the plaintiff, or that any portion of the ground claimed by the defendants had ever been previously located or claimed; that their discovery cut was commenced at a point thirty-five feet distant from the point described and claimed by Carroll as the point at which he had begun to sink the discovery shaft of the "Hawk Lode," and erected his stake and posted his notice, and that the top of the vein was at least four feet below the surface; that Carroll had abandoned all claim to the premises in controversy, and that his omission to perform the required location work was due to such abandonment, and not to any threats of the defendants, or of any of them, nor to the occupation of the ground by Boaro and Hull, or either of them; that neither the plaintiff nor Carroll ever demanded possession of or asserted any title to the premises until the working of the claim by the defendants had shown it to be valuable.
 The evidence of the defendants also showed that they had commenced work upon the claim about July 21, 1880, and sank and excavated an open cut, striking the vein or lode at the depth of ten feet or more, and exposed therein a vein of rock in place bearing gold and silver; that no mineral nor any indications of a vein or lode were found until they reached the depth of seven or eight feet, and that subsequently, and within the time limited by law, they marked the bounds of their claim on said lode, called by them the "Johnny Bull Lode" and recorded a location certificate, describing their claim by reference to natural objects and permanent landmarks and complying in all respects with the requirements of the law.
 The court was requested to instruct the jury that from and after the date of the discovery upon vacant, unoccupied mineral lands, of the outcrop of a vein or body of mineral-bearing rock, the discoverer is entitled to the possession of the point at which he made his discovery and of such a reasonable amount of adjacent ground as is necessary or incidental to the proper prosecution of the work of opening up or exposing the vein or body of mineral-bearing rock to the depth and within the time required by law, and that to such extent he is protected by law in his possession for the period of sixty days from the date of his discovery. But the court refused to give this instruction, and the plaintiff excepted to the refusal. The court charged the jury, among other things, that it was in evidence, and seemed to be conceded, that the notice on the stake put up by Carroll contained no specification or description of the territory claimed by the locators, as that they claimed a number of feet on each side of the discovery or in any direction therefrom, and "in this respect," said the court, "the notice was deficient, and under it the locators could not claim more than the very place in which it was planted. Elsewhere on the same lode or vein, if it extended beyond the point in controversy, any other citizen could make a valid location, for this notice, specifying no bounds or limits, could not be said to have any extent beyond what would be necessary for sinking a shaft," and also that to entitle the plaintiff to recover, "it should appear from the evidence that Boaro entered at the very place which had been taken by Carroll, because, as Carroll's notice failed to specify the territory he wished to take, it could not refer to or embrace any other place than that in which it was planted."
 The defendant obtained a verdict, the plaintiff brought the case to the high court on writ of error to review the judgment entered thereon.
 Justice Field delivered the opinion of the Court.
 As seen by the statement of the case, the court below, in its charge, assumed that the notice on the stake placed by Carroll at the point of his discovery contained no specification or description of the ground claimed by the locators because it did not designate the number of feet claimed on each side of that point, or in any direction from it. The court accordingly instructed the jury that the notice was deficient, and under it the locators could not claim any more than the very place in which the stake was planted, and that elsewhere on the same lode beyond the point of discovery, any other citizen could make a valid location.
 In this instruction we think the court erred. The statute allows the discoverer of a lode or vein to locate a claim thereon to the extent of 1,500 feet. The written notice posted on the stake at the point of discovery of the lode or vein in controversy, designated by the locators as "Hawk Lode," declares that they claim 1,500 feet on the "lode, vein, or deposit." It thus informed all persons subsequently seeking to excavate and open the lode or vein that the locators claimed the whole extent along its course which the law permitted them to take. It is indeed indefinite in not stating the number of feet claimed on each side of the discovery point, and must therefore be limited to an equal number on each side -- that is, to 750 feet on the course of the lode or vein in each direction from that point. To that extent, as a notice of discovery and original location, it is sufficient. Greater particularity of description of a location of a mining claim on a lode or vein could seldom be given until subsequent excavations have disclosed the course of the latter. These excavations are to be made within sixty days after the discovery. Then the location must be distinctly marked on the ground, so that its boundaries can be readily traced, and, within one month thereafter -- that is, within three months from the discovery -- a certificate of the location must be filed for record in the county in which the lode is situated containing the designation of the lode, the names of the locators, the date of the location, the number of feet claimed on each side of the center of the discovery shaft, the general course of the lode, and such a description of the claim, by reference to some natural object or permanent monument, as will identify it with reasonable certainty. Rev.Stat. § 2324; Gen.Laws of Colorado §§ 1813, 1814.
 But during the intermediate period from the discovery of the lode or vein and its excavation, a general designation of the claim by notice, posted on a stake placed at the point of discovery, such as was posted by Carroll, stating the date of the location, the extent of the ground claimed, the designation of the lode, and the names of the locators, will entitle them to such possession as will enable them to make the necessary excavations and prepare the proper certificate for record. The statute of Colorado requires that the discoverer, before a certificate of location is filed for record, shall, in addition to posting the notice mentioned at the point of discovery, sink a shaft upon the lode to the depth of at least ten feet from the lowest part of such shaft under the surface, or deeper, if necessary, to show a defined crevice and to mark the surface boundaries of the claim. Before this work could be done by the plaintiff and his co-locator the ground claimed by them was taken possession of by the defendants, the stake at the point of discovery, upon which the notice was posted, was removed and Carroll was thereby, and by threats of violence, prevented from reentering upon the premises and completing the work required to perfect their location and prepare a certificate for record -- at least the evidence tended to establish these facts. If they existed -- and this was a question for the jury -- the plaintiff was entitled to recover possession of the premises. To the extent of 750 feet on the course of the lode on each side from the point of discovery, he and his co-locator were entitled to protection in the possession of their claim. They did not lose their right to perfect their location and perform the necessary work for that purpose by the wrongful intrusion upon the premises and by threats of violence if they should attempt to resume possession. As against the defendants, they were entitled to be reinstated into the possession of their claim. They could not be deprived of their inchoate rights by the tortious acts of others; nor could the intruders and trespassers initiate any rights which would defeat those of the prior discoverers.
 The government of the United States has opened the public mineral lands to exploration for the precious metals, and, as a reward to the successful explorer, grants to him the right to extract and possess the mineral within certain prescribed limits. Before 1866, mining claims upon the public lands were held under regulations adopted by the miners themselves in different localities. These regulations were framed with such just regard for the rights of all seekers of the precious metals, and afforded such complete protection, that they soon received the sanction of the local legislatures and tribunals, and when not in conflict with the laws of the United States or of the state or territory in which the mining ground was situated, were appealed to for the protection of miners in their respective claims and the settlement of their controversies. And although since 1866 Congress has to some extent legislated on the subject, prescribing the limits of location and appropriation and the extent of mining ground which one may thus acquire, miners are still permitted, in their respective districts, to make rules and regulations not in conflict with the laws of the United States or of the state or territory in which the districts are situated governing the location, manner of recording, and amount of work necessary to hold possession of a claim. Rev.Stat. § 2324. In all legislation, whether of Congress or of the state or territory, and by all mining regulations and rules, discovery and appropriation are recognized as the sources of title to mining claims, and development by working as the condition of continued ownership until a patent is obtained. And whenever preliminary work is required to define and describe the claim located, the first discoverer must be protected in the possession of the claim until sufficient excavations and development can be made so as to disclose whether a vein or deposit of such richness exists as to justify work to extract the metal. Otherwise the whole purpose of allowing the free exploration of the public lands for the precious metals would in such cases be defeated, and force and violence in the struggle for possession, instead of previous discovery, would determine the rights of claimants.
 It does not appear in this case that there were any mining regulations in the vicinity of the "Hawk Lode" which affect in any respect the questions involved here. Had such regulations existed, they should have been proved as facts in the case. We are therefore left entirely to the laws of the United States and the laws of Colorado on the subject. And the laws of the United States do not prescribe any time in which the excavations necessary to enable the locator to prepare and record a certificate shall be made. That is left to the legislation of the state, which, as we have stated, prescribes sixty days for the excavations upon the vein from the date of discovery and thirty days afterwards for the preparation of the certificate and filing it for record. In the judgment of the legislature of that state, this was reasonable time. This allowance of time for the development of the character of the lode or vein does not, as intimated by counsel, give encouragement to mere speculative locations -- that is, to locations made without any discovery or knowledge of the existence of metal in the ground claimed with a view to obtain the benefit of a possible discovery of metal by others within that time. A mere posting of a notice on a ridge of rocks cropping out of the earth or on other ground that the poster has located thereon a mining claim, without any discovery or knowledge on his part of the existence of metal there or in its immediate vicinity, would be justly treated as a mere speculative proceeding, and would not itself initiate any right. There must be something beyond a mere guess on the part of the miner to authorize him to make a location which will exclude others from the ground, such as the discovery of the precious metals in it or in such proximity to it as to justify a reasonable belief in their existence. Then protection will be afforded to the locator to make the necessary excavations and prepare the proper certificate for record. It would be difficult to lay down any rules by which to distinguish a speculative location from one made in good faith with a purpose to make excavations and ascertain the character of the lode or vein, so as to determine whether it will justify the expenditures required to extract the metal, but a jury from the vicinity of the claim will seldom err in their conclusions on the subject.
 
This case, as appears by the record, is brought in the name of one of the locators, Erhardt, who owns only four-fifths of the claim. But as a tenant in common with Carroll, he can maintain an action of ejectment for the possession of the premises, the recovery being not merely for his benefit, but for that of his co-tenant, who is equally entitled with him to the possession. The high court reversed the judgment of the court below, and the case remanded for a new trial.