delivered the opinion of the Court:
The important question presented by this record is, whether, under the statute giving municipal corporations control of the streets and alleys within the municipality, power exists in the corporate authorities to vacate a street, or a portion of a street, for the benefit and use of a private person.
It is charged, and the answer practically admits, and, indeed, the ordinance on its face purports, that the attempted vacation of a strip five feet wide and eighty-five feet long, off of the side of the street, was for the single purpose of permitting its use by appellant Smith, president of the board of trustees of the village, as an area-way, connected with the basement of his proposed building. The doctrine is sought to be invoked, that the motives of the trustees of the village in the passage of the ordinance can not be judicially inquired into. That position is at once conceded. ' Whether their motives were honest or otherwise, in voting for the ordinance, is not a subject of inquiry. But the purpose accomplished by the ordinance,—the object attained,—may always be considered, indeed, must be, in determining the validity of the ordinance. If the purpose effected by the ordinance is within the power of the city council, their act will be valid. The question to be 'determined is one of power in the municipality, in the determination of which, the legal effect of the action of the municipality becomes the controlling matter for consideration. *61In Ligare v. Chicago, 139 Ill. 46, it was held that the effect— the result—of the action of the city council was the exclusion of the general public from a portion of the public street opened and sought to be opened, and the power of the city to so exclude the public was denied. No such purpose was expressed in the ordinance, but that being th'e effect of what was done, the court looked to the result, and that result requiring the exercise of power not conferred upon or existing in the municipality, the ordinance was declared void.
The answer avers, that under and by virtue of the ordinance, in this case, Smith had taken possession of the locus in quo, excavated for and erected a stone area-wall, enclosing the strip of the street proposed to be vacated.. The purpose sought to be attained, and actually accomplished, if the ordinance is valid, is not left in doubt. This strip of ground was to be delivered over to Smith for his private use, and the control of the municipality over the same, as a part of a public street of the village, extinguished.
Before proceeding farther it will be proper to notice the contention that the court erred in sustaining exceptions to portions of the answer. The practice in chancery, in this State, in respect of exceptions to answers, which are mere pleadings, the verification having been waived in the bill, has been so repeatedly determined that no discussion will be necessary. (Board of Supervisors v. M. and W. Railway Co. et al. 21 Ill. 338; Brown v. Scottish-American Mortgage Co. 110 id. 235 ; Mix v. The People, 116 id. 265.) Conceding, in view of these authorities, that the court erred in this respect, it is manifest that defendants were not prejudiced thereby. A careful examination of the answer will fail to disclose a single averment of fact, to which exception was sustained, which, if retained and proved in the most ample manner, would have changed the result. Thus, proof of the fact that it was agreed between the village and Smith that he should enclose the area-way with a substantial iron railing, and extend the sidewalk around *62it, and the like facts, would in nowise affect the question of whether a purpresture was created in the street, or the power of the village authorities to vacate that portion of the street for the private use contemplated.
It is contended, first, that the power of the village authorities to vacate streets is plenary, and that they having, in the exercise of their legislative discretion, vacated the strip of ground mentioned, their action is not the subject of judicial review; and secondly, if the vacating ordinance be invalid, it is nevertheless a license to Smith to occupy that portion of the street, and such occupancy by him is not therefore a nuisance.
It is insisted, that as the statute (Rev. Stat. chap. 24, par. 63, clause 7,) grants power to municipalities organized under the general Incorporation act “to lay out, establish, open, alter, widen, extend, grade, pave or otherwise improve streets, alleys, avenues, sidewalks, wharves, parks and public grounds, and vacate the same,” the power to vacate is absolute, to be exercised in the discretion of the municipal authorities. We can not concur in this vi^w. By the platting of the village the streets, in their entire width and length, were dedicated to the use of the public, as streets. The village thereby became seized in fee of the streets and alleys, for the use of the local and general public, holding them in trust for such uses and purposes, and none other. (Alton v. Transportation Co. 12 Ill; 38; Carter v. Chicago, 57 id. 285; Chicago v. McGinn, 51 id. 266; Jacksonville v. Jacksonville Railway Co. 67 id. 540; Quincy v. Jones, 76 id. 231; Kreigh v. Chicago, 86 id. 410; Stack v. East St. Louis, 85 id. 377; Lee v. Mound Station, 118 id. 312.) These municipal corporations are instrumentalities of the State, exercising such powers as are conferred upon them in the government of the municipality. Their power is measured by the legislative grant,, and they can exercise such powers only as are expressly granted, or are necessarily implied from the powers expressly *63conferred. The legislature representing the great body of the people of the State, when no private right is invaded or trust violated, (Jacksonville v. Jacksonville Railway Co. supra,) may repeal the law creating them, or exercise such control in respect of the streets, alleys and public grounds, within the municipalities of the State, as it shall deem for the interest of the people of the State. Dillon on Mun Corp. sec. 541; Chicago v. Rumsey, 87 Ill. 355; The People v. Walsh, 96 id. 253; Chicago v. Union Building Ass. 102 id. 397; West Chicago Park Board v. McMullen, 134 id. 170.
It does not follow, however, as seems to be supposed, that by the,use of the general words, “and vacate the same,” the absolute power of the legislature was intended to be conferred upon the municipal authorities. The grant of power in this particular is to be construed in view'of the purposes for which the municipality is invested with the control of its streets, alleys and public grounds. The municipality, in respect of its streets, is a trustee for the general public, and holds them for the use to which they are dedicated. The fundamental idea of a street is, not only that it is public, but that it is public in all its parts, for free and unobstructed passage thereon by all persons desiring to use it.
In Alton v. Transportation Co. supra, we said, in treating the subject there under consideration: “Whatever title to these public grounds may be vested in the city, she has not the unqualified control and disposition of them. They were dedicated to the public for particular purposes, and only for such purposes can they be rightfully used. For these purposes the city may improve and control them, and adopt all needful rules and regulations for their management and use, but she can not alien or otherwise dispose of them. At most, she but holds them in trust for the benefit of the general public.” In Quincy v. Jones, supra, after quoting with approval the foregoing language, it is said: “It is the unquestioned duty of the city, in controlling and improving the streets, to prepare *64them for public use as streets, * * * as the public necessity may require. Holding them in trust for the public, and having no authority to convey or divert them to other uses, it would seem inevitably to follow that they can have no power to grant to individuals rights or easements in the street which might in any way interfere with the duty of preparing them for public use.” And in Chicago Dock Co. v. Garrity et al. 115 Ill. 155, in considering the power of the municipality to grant rights in the public streets of the city, it was said: “It is not claimed that the use of the streets can be permanently granted for private purposes, and we recognize as unquestionable law that the use of the streets * * * must be for the public, and that no corporation or individual can acquire an exclusive right to their use, or to the use of any part of them, for private purposes.” In Glasgow v. St. Louis, 87 Mo. 678, under power “to establish, open, vacate, alter, widen, extend, pave or otherwise improve all streets,” etc., it was held, that an ordinance to vacate a portion of one of the streets of the city for the use of private parties was ultra vires. See, also, Reimer’s Appeal, 100 Pa. St. 182; St. Vincent’s Orphan Asylums. Troy, 76 N. Y. 108; State v. Berdetta, 73 Ind. 185; Belcher Sugar Refinery Co. v. St. Louis, etc. Co. 82 Mo. 127; Dubash v. Hannibal and St. Joe Railroad Co. 89 id. 86.) And we held that the city can not acquire land by condemning the same for a street, when the real purpose is to devote it to a private use. (Ligare v. Chicago, supra.) In the Belcher Sugar Refinery Co. case, supra, the court held that the corporation could not condemn the property for a public use, to be appropriated to a private use. It in nowise affects the principle involved, whether the street is acquired by dedication or condemnation. Glasgow v. St. Louis, supra.
The municipal corporation holding and controlling its streets in trust for the use of the general public, without power of converting them to any other use, it follows, necessarily, that the right to “vacate the same” is to be exercised *65only when the municipal authorities, in the exercise of their discretion, determine the street is no longer required for the public use or convenience, and the case of Meyer v. Village of Teutopolis, 131 Ill. 552, is, when properly understood, not in conflict with the views'here expressed. See Ligare v. Chicago, supra.
It is not necessary to here discuss or determine whether the courts will, in any case, interfere to prevent the abuse of municipal discretion in the respect mentioned, for the reason that it is not sought to restrain the exercise of such discretion, but to prevent the perversion of their power to the promotion of private interests, in violation of the trust upon which the streets are held. (Carter v. Chicago, supra.) In this case there is no pretence that the public interest required the vacation of any part of the street, or that any public interest, local or general, would be subserved by the proposed vacation. The ordinance, professedly and in terms, proposes to destroy the public right and use, for the sole purpose of enabling a private person to occupy a portion of the street with a permanent structure, appurtenant to his building abutting upon the street. This the municipal authorities are not empowered to do, and their action was ultra vires and void.
The other contention, even if the ordinance could be regarded as a license to Smith to permanently occupy a portion of the street, is equally untenable. As we have seen, the primary purpose of a street is for public use, and that it is not within the power of the municipality to divert the street to permanent private uses. It by no means follows that every obstruction of a street is a purpresture, or illegal. Thus, the necessary and temporary obstruction incident to the use or repair of the street; the interruption that may be caused by the temporary depositing of earth or material in improving the adjoining lots; excavations under the street authorized by the municipality, and the like, (Gridley v. Bloomington, 68 Ill. 47,) if temporary and reasonably -necessary, must be borne, *66as a reasonable and necessary limitation of the free and uninterrupted right of use by the public, and when made under proper regulations, and with reasonable safeguards against accident, such interruptions are not to be regarded as nuisances, the test in all such cases being, that the interruption shall be reasonably necessary, and not continued for an unreasonable time. (2 Dillon on Mun. Corp. 581, et seq. and authorities cited; Angelí on Highways, ch. 6; Wood on Law of Nuisances, 262, et seq.) And so in respect of iron gratings to admit light, openings for admission of coal, flap or trap-doors,, the extension of signs into the street, and the like, if authorized by the municipality, and properly constructed, so as not to interfere with the public use of the street or sidewalk, are not to be regarded as nuisances. But it is indispensable, to-take from the use of the street, for such purposes, the character of a nuisance, that the street or sidewalk be left free for the public use, and in as safe condition as it would have been without such use, for the city government can not exempt itself from liability for injuries resulting from an unsafe condition of the streets or any part of them, and can not delegate to others authority to make them so, for although such occupation of the street may not be a nuisance, yet the owner- or person creating the obstruction, or using it, and the city, after notice, will be liable for negligence in its construction or maintenance. (Wood on Law of Nuisances, 275, et seq., and cases cited; Dillon on Mun. Corp. supra; Elliott on Boads and Streets, 480-540.) Every person passing over the street has a right to presume that it is in proper condition, and in every way safe for the purpose of his passage, with due and ordinary care, and as the municipality itself can not be justified in creating a nuisance, no one can justify the creation of a nuisance under a license from it.
The distinction between these uses of the street, when authorized, and that proposed in this case, is well defined. That the obstruction extending into the street five feet, and for the *67length of eighty-five feet, was intended to be, and was, permanent, is not questioned. It was for use as an area-way, adjoining the basement of the brick building to be erected upon the adjacent lot, flush with the lot line. It was surrounded by a stone wall, on the top of which was to be placed an iron railing, and the sidewalk was to be extended around it. Its perpetual use was necessary for the purpose for which it was designed, and if the ordinance be treated as a license, merely, the right to so maintain it in the public street, to the exclusion of the public, and for the exclusive benefit of the abutting lot owner, w'as intended to be conferred. This being so, it falls within the definition of a purpresture, (4 Blackstone’s Com. 167,) and is, per se, a public nuisance, which the village authorities had no power to license or maintain. Wood on Law of Nuisances, 238, et seq.
The 221st section of the Criminal Code (1 Starr & Curtis, 815,) provides: “It is a public nuisance: * * * 5. To obstruct or encroach upon public highways, * * * streets, alleys, commons, ” etc. “The king, ” says Judge Dillon, (Mun„ Corp. sec. 521,) “can not license the erection or commission of a nuisance, nor, in this country, can a municipal corporation do so by virtue of any implied or general power. A building, or other structure of like nature, erected upon a street without the sanction of the legislature is a nuisance, and the local corporate authorities of a place can not give a valid permission thus to occupy the streets, without express power to this end conferred upon them by charter or statute.” (See note.) Wood, in his Law of Nuisances, (sec. 742,) lays down the rule, that “while a municipal corporation may provide, by ordinance, for the prevention and removal of, yet it can not license, a nuisance, nor can it maintain a nuisance upon city property, but is subject to the same liabilities and remedies therefor, at the suit of persons injured or in behalf of the public, as an individual would be.” These texts are amply-sustained by the decided cases cited.
*68In Pettis v. Johnson, 66 Ind. 139, the city of Indianapolis contracted with the owners of a building situated upon one of the public alleys of the city, that they should construct a stairway in the alley, to afford access to rooms in the building, occupied by officers of the city. The structure being permanent in its character, it was held to be a nuisance, and abated accordingly. The court says: “The city had no power to contract for such a structure in such a place. True, the city has exclusive jurisdiction over the streets and alleys, not to enable it to appropriate them or any part of them, in perpetuity, to the use of private individuals, but to keep them, so far as may be, open and free to all, and so regulate and control necessary temporary obstructions that they shall not become permanent.” Pfau v. Reynolds, 53 Ill. 212; Commonwealth v. King, 13 Metc. 115; State v. Berdetta, supra; Hart v. Mayor, 3 Paige, 213; The People v. Cunningham, 1 Denio, 524, and cases supra.
The permanent encroachment upon a public highway or street unauthorized by the legislature, and the creation of a purpresture therein, which obstructs the free and uninterrupted passage of the public, is, as a matter of law, a public nuisance. The matter of inconvenience to the public, or that sufficient of the street may remain unobstructed to still accommodate the public travel, can not be considered. The trustee of the public,—the municipality,—is charged with the duty of keeping and maintaining the streets, in all their parts, open and unobstructed, and in reasonably safe condition for the public use. No question of the amount of damage done or that may ensue from the creation of the purpresture is raised, nor can it be considered in proceedings by the public, the question being, simply, whether there has been an invasion of the public right. Where the proceedings are instituted by a private individual for a public nuisance, the gist of his right of action is the private injury, and he must allege and prove some special damage, different in kind from that *69suffered by the general public. (McDonald v. English, 85 Ill. 232; Chicago v. Union Building Ass. 102 id. 379; East St. Louis v. O’Flynn, 119 id. 200.) The public may institute proceedings for the abatement or prevention of the nuisance, by its authorized public officers, irrespective of the question of pecuniary damage. (Jackson et al. v. Norris, 72 Ill. 364; Hunt v. Chicago Horse and Dummy Railway Co. 121 id. 638.) Nor does it seem to be necessary, when the erection is, itself, an invasion of the public right,—that is, where it is a nui- ' sanee per se,—that the fact should be established at law, preliminary to the jurisdiction by injunction. The public is entitled to the speediest and most effectual way to prevent the threatened invasion of its right. (Wood on Law of Nuisances, secs. 777, 786; Dillon on Mun. Corp. 520 ; State v. Mayor of Mobile, 5 Port. 279; Reimer’s Appeal, supra; Attorney General v. Vanderbilt, 26 N. Y. 287; Manhattan v. Barker, 7 Robt. 723; Eden on Injunctions, 11-159.) And if there has been a clear invasion of the common right, — the unauthorized taking for private use of that which belongs to the public, as, by the permanent occupation of a public street, or a portion of it,—injunction will be granted, at the suit of the proper officer, on behalf of the public, to prevent the creation and maintenance of the nuisance. 3 Pomeroy’s Eq. 1359, and note; Earle v. DeHart, 1 Beasley, (N. J. Eq.) 280 ; Sparhawk v. Union, etc. Railroad Co. 54 Pa. St. 401; East India Co. v. Vincent, 2 Atk. 83 ; Murdock’s case, 2 Bland. Ch. 461; 29 Am. Dec. 389, notes.
We are of opinion that the chancellor decided correctly, and the decree of the circuit court will be affirmed.