Lake Monona is a meandered lake, navigable in fact. The title to its bed is in the state in trust for legitimate public uses, such as fishing, navigation, and the like; and the state cannot convey it away for private uses, nor can it abdicate the trust. McLennan v. Prentice, 85 Wis. 427; Priewe v. Wis: State L. & L. Co. 93 Wis. 534; Mendota Glub v. Anderson, 101 Wis. 479; Pewaukee v. Savoy, 103 Wis. 271; Stats. 1898, sec. 1607a. A structure built upon the bed of the lake, not in aid of navigation (e. g. a building in which to store and repair boats), is a purpres-*540ture,— an invasion, both of the state’s title and the rights of the public. A pier may lawfully be built by a riparian owner in aid of navigation, through shoal water to navigable water, if not prohibited by state law; but, if built by one not a riparian owner, it is an unauthorized structure, and an invasion of the rights of the state and the public, because the right to erect such a pier is simply an incident of riparian ownership. Larson v. Furlong, 63 Wis. 323; Cohn v. Wansau B. Co. 47 Wis. 314. Applying these legal principles to the facts as found by the trial court (which are amply supported by the evidence), it is entirely clear that the boat house was and is a purpresture, because it is not an aid to navigation, and that the pier is a purpresture, because those who built and maintain it are not riparian owners; and these were the conclusions reached by the trial court.
The trial court further held, however, that the relator was not a riparian owner; that the structures were not shown to be actually obstructions to navigation, or nuisances in fact, but, rather, conveniences to the public; and that the attorney general having taken no active part in the litigation, and declining to come into court and ask judgment of abatement on behalf of the state, the court, sitting as a court of equity, would not abate the structures.
With the first proposition, namely, that the relator is not a riparian owner, we entirely agree. The deed made by Dean to the railway company in 1868 was a deed conveying in fee simple the southeast end of the lot, and covered the shore line; the railway company had power by its articles of association, “ to acquire, use, and sell, bargain, lease, and convey, all kinds of property, real and personal, necessary or convenient to operate, use, or maintain its railroad.” Rut the appellant’s contention is that the railway company could only acquire an easement or limited fee in lands to be used for right-of-way purposes, and that hence, notwithstanding the language of the deed, it must be construed as simply *541conveying such easement, and that the relator, having hy subsequent deed acquired the southeast end of the lot, owns the shore and all riparian rights, subject only to the easement of the railway company. New York Central & H. R. R. Co. v. Aldridge, 135 N. Y. 83; S. C. 17 L. R. A. 516. It was held by this court nearly twenty years ago, in the case of Messer v. Oestreich, 52 Wis. 684, that, when a railway company received a warranty deed of a strip of land for its track, the company did not take a mere easement, but a title in fee, subject at most to forfeiture for nonuser or misuser. If it be granted that the railway company had no power to acquire a fee in its right of way, but only an easement therein, still the making and delivering to it of a deed of the fee would transfer the title. The transaction would be ultra vires, but, upon principles now well established, it would be valid until assailed in a direct proceeding brought for that purpose by the government. Private persons could not attack it in collateral actions. John V. Farwell Co. v. Wolf., 96 Wis. 10. The relator is not, therefore, a riparian owner, and suffers no private injury.
Thus far we agree, in substance, with the conclusions reached below. The trial judge, however, concluded that navigation was in no way injured by the structures, and so, although they were purprestures, they were not public nuisances; that, the.attorney general not appearing in court and asking abatement thereof on behalf of the state, a court of equity would not abate them. With this conclusion we cannot agree. It is true that a purpresture on the public land is not necessarily a public nuisance. Gould, Waters (2d ed.), § -21. A purpresture is a permanent invasion of the public land. A nuisance is an injury to the public rights of navigation, fishing, and the like. It is true that it has been held in California that a court of equity in this country has- not the power to decree the abatement of a mere purpresture which is not a public nuisance. People ex rel. *542Teschemacher v. Davidson, 30 Cal. 379. A different conclusion was, however, reached in People v. Vanderbilt, 26 N. Y. 287, whfere it was distinctly held that a mere purpresture is liable to abatement in an action in equity at the suit of the attorney general, irrespective of the question whether it is actually a nuisance, and that the offer to prove that a pur-presture, such as a pier in navigable waters, was not in fact injurious to navigation, was properly overruled. Similar conclusions were reached in Pevell v. People, 177 Ill. 468, and U. S. v. Brighton P. Co. 25 Fed. Rep. 465. The authorities cited in those cases entirely justify the decisions, and we have no hesitation in adopting the latter rule.
The complaint before us was framed in the double aspect of a complaint to ’enforce the rights of the state and the private rights of an alleged riparian owner as well, but the proof showed that there were no riparian rights in the re-1 ator. The case of the state, however, remained fully proven and unaffected by the failure of the private claim. Thus it stood when judgment was rendered: A complaint charging a purpresture on the lands of the state, and demanding its removal, filed by the proper officer. The proof showing all the facts essential to a judgment as prayed in the complaint. The attorney general had not-withdrawn, nor attempted to withdraw, the complaint, or discontinue the action. We cannot but think that, under the circumstances, it was the duty of the court to render judgment of abatement. What might have been the duty of the court had the attorney general applied for leave to discontinue as to the public right, we need not consider, for there was no such application. Judgment of abatement of the illegal structures, as invasions of the public domain, should have been rendered.
By the Court. — -Judgment reversed, and action remanded with directions to render judgment for the plaintiff as prayed in the complaint.