enjoins upon the plaintiff a degree of care commensurate with the danger, and is admissible as tending to show contributory negligence. City of Sandwich v. Dolan, 141 Ill. 430; 31 N. E. Rep. 416; Village of Clayton v. Brooks, 150 Ill. 97; 37 N. E. Rep. 574; Town of Poseyville v. Lewis, 126 Ind. 80; 25 N. E. Rep. 596; Norwood v. City of Somerville, 159 Mass. 105; 33 N. E. Rep. 1108; Finn v. City of Adrian, 93 Mich. 504; 53 N. W. Rep. 614; McGrail v. City of Kalamazoo, 94 Mich. 52; 53 N. W. Rep. 955; Dittrich v. City of Detroit, 98 Mich. 245; 57 N. W. Rep. 125; Flynn v. City of Neosho, 114 Mo. 567; 21 S. W. Rep. 903. While it is certain that previous knowledge of the existence of a defect in a street or sidewalk has an important and oftentimes a decisive bearing upon the question of contributory negligence, mere inattention on the part of a person injured by reason of such defect will not conclude him upon that question. It is not necessary that the thoughts of a traveler should at all times be fixed upon a defect in a public thoroughfare, of which he may have had notice. Maloy v. City of St. Paul, 54 Minn. 398; 56 N. W. Rep. 94. If a person, with full and present knowledge of the defective condition of a sidewalk, and of the risks incident to its use, voluntarily attempts to travel upon it, when the defect could easily and without appreciable inconvenience have been avoided by going around it, he is not in the exercise of reasonable care, but must be presumed to have taken his chances, and if injury results he cannot recover from the city. Wright v. City of St. Cloud, 54 Minn. 94; 55 N. W. Rep. 819. Where a person knew that a bridge was in a dangerous and unsafe condition, and yet undertook to drive over it without apparent necessity, it was held that he was guilty of contributory negligence and could not recover. Cohen v. City of Coffeeville, 69 Miss. 561; 13 South. Rep. 668. In an action against a county to recover for injuries sustained by being thrown from a buggy by a patent defect in the highway, where it appeared that plaintiff deliberately and carelessly, seeing the defect, drove over it, or that her failure to see it was the proximate cause of injury, she cannot recover. Magill v. Lancaster County, 39 S. C. 27; 17 S. E. Rep. 507. Where signboards bearing in large letters the inscription "Bridge unsafe" are placed conspicuously at each end of a defective bridge, and are of such construction as to given warning of the unsafe condition of the bridge, the fact that a traveler is unable to read English does not excuse his attempting to cross the bridge, and in doing so he is guilty of contributory negligence. Weirs v. Jones County, 86 Iowa, 625; 53 N. W. Rep. 321. FIELD ET AL. v. BARLING ET AL. (Supreme Court of Illinois, April 2, 1894.) 1. MUNICIPAL CORPORATIONS. POWER TO GRANT USE OF STREETS FOR PRIVATE PURPOSES. BRIDGE OVER ALLEY. An ordinance granting to private parties the right to construct for their own use a bridge over a public alley is invalid, since cities hold the fee of the streets in trust for public uses only. 2. RIGHT OF ABUTTING OWNER TO ENJOIN PRIVATE ERECTIONS OVER ALLEY. SPECIAL DAMAGE. Where a proposed obstruction in a public alley inflicts special damage on the owner of an adjoining lot, he is entitled to an injunction restraining its erection. 3. Where the answer to a bill to enjoin the erection of a bridge across a public alley admits an intention to erect the bridge, and describes it specifically, and it appears that defendants have no right to erect any bridge in such alley, it is proper to enjoin them from erecting any bridge across the alley, without limiting the injunction to the particular kind of bridge proposed to be erected. 4. RIGHTS OF ABUTTING OWNERS IN PLATTED STREETS AND ALLEYS. Where land is platted by the owner into lots, blocks, streets and alleys, and lots are sold by him with reference to the plat, the purchasers acquire, as appurtenant to the lots, the right to have the adjoining streets and alleys kept clear of obstructions both on and above the ground. BILL for injunction brought by Henry A. Barling and others against Marshall Field, John M. Pashley and others. Complainants obtained a decree. Defendants appeal. Wilson, Moore & McIlvaine, for appellants. Geo. L. Paddock (John J. Herrick, of counsel), for appellees. CRAIG, J. This was a bill brought by Henry A. Barling, Edward H. Green and Edward D. Mandell, trustees under the will of Edward Mott Robinson, deceased, against Marshall Field et al. to enjoin them from building or constructing any building, bridge, passageway or other construction on, upon or across the alley known as Holden place or court, between the north line of Washington street and complainants' property described in the bill. The block in the city of Chicago bounded by Wabash avenue, Randolph, State and Washington streets, is known as block 13 of Ft. Dearborn addition to Chicago. The land, when platted, belonged to the United States, and the plat of Ft. Dearborn addition was executed and recorded in June, 1839. The following plat shows State street, Washington street and Wabash avenue, and Randolph street as originally laid out; also Holden place. The plat also shows the location of complainants' property, and the location of Field's old building, and the new one, and the point where it was proposed to erect the bridge across Holden place, connecting the two buildings. Washington Street Holden place, as will appear from the plat, is forty feet wide, extending north and south, through blocks 13 and 14, with lots on each side; those on the east fronting on Wabash avenue, those on the west fronting on State street. Holden place has been used as a public place or street for many years. The defendants' lots on the northeast corner of Washington and State streets, have a frontage of 160 feet on State, extending back to Holden place, covered by a six-story building, occupied by Marshall Field & Co. for several years as a dry-goods house. The defendants have acquired lots on northwest corner of Wabash avenue and Washington street, with a frontage of 108 feet on Wabash avenue, extending back to Holden place. On the latter lots the Wabash Avenue appellants commenced the erection of a new building, nine stories high. At the time of the filing of the bill the new building had been erected six stories high, and the appellants were about to commence the erection of a bridge or passageway over Holden place, connecting the old and new buildings. The bridge or passageway, as disclosed by the answer, was to be eighteen feet above the surface of Holden place, three stories in height, extending north from Washington street over the alley, the entire width of the alley, the distance of forty feet and upward, fifty-five feet or seventy-three feet above the ground. It is charged in the bill that "the effect of said construction of such connecting building, if the same be not prevented by this honorable court, will be to deprive your orators' said building and the occupants thereof, to a great extent, of sunshine, light, air and warmth, which they have hitherto enjoyed, by reason of the opening and keeping open of said court or alley from the time of said platting and subdivision down to the present; will give said alley an appearance of a private gateway and passage; will hinder and deter traffic, and in many other ways cause serious and continuing damage to your orators and their property; that such damage will amount to many thousands of dollars, and will be beyond legal remedy or relief, if not prevented by this court." It is also alleged that orators and Marshall Field & Co. and the other defendants held their respective lands on said block 13 under a common source of title, viz., the United States, by patents made by the United States in pursuance of a subdivision plat and sales by the United States; "that by reason of the exhibition and publication of the said subdivision and plat, and by the sale of lots thereunder to the respective grantors of your orators and the said defendants Marshall Field & Co., or said Marshall Field, for their use, there has resulted, as between your orators and the said Marshall Field & Co., or such of them as own the said properties so fronting south on Washington street, on either side of said alley, a right in law to have the said alley remain absolutely and wholly open forever, of the same dimensions and to the same extent as delineated by the United States upon the subdivision and plat aforesaid, viz., from the north line of Washington street, forty feet in width, to the south line of Randolph street, and upwards to the sky." In the answer the appellants admit the intention to build the proposed bridge or structure over and across Holden place, but deny that it will interfere with the light, air and ventilation of complainants' premises, or that it will in any manner injure complainants. The appellants also set up and rely upon an ordinance set out in complainants' bill, passed by the city of Chicago June 6, 1892. Section 1 of the ordinance is as follows: "Be it ordained by the city council of the city of Chicago: Section 1. That permission and authority be and is hereby given to John M. Pashley and his assigns to construct and use a bridge or covered passageway across the alley running between lots 9, 10 and 11 on one side, and lot 6, in assessor's subdivision of lots 6, 7 and 8, etc., on the other, all in block 13, Fort Dearborn addition to Chicago; provided, the lowest portion of said bridge or passageway shall not be lower than eighteen feet above grade of alley, and shall be so constructed that free and unobstructed passage may be had under the same; and provided, that said bridge or passageway shall be constructed of incombustible material and to the satisfaction of the commissioner of buildings." Section 2 provides that Pashley, or his assigns, and all persons who shall occupy the buildings which the bridge is to connect, shall indemnify and save the city of Chicago harmless from all damages which it may become liable for by reason of the passageway granted. It will not be necessary to cite authorities in support of the proposition that a private individual cannot appropriate to his own exclusive use a portion of the surface of a street dedicated to the public use. Before Holden place was dedicated to the public as a street, the title of the United States, the original proprietor, was not confined to the surface of the ground, but its title extended upward, embracing the light and air as well as the soil; and the dedication of the strip of land for a public street embraced not only the surface of the ground, but the light and air above, and an individual has no more right to obstruct the light and air above the street than he has to obstruct the surface of the soil. In Barnett v. Johnson, 15 N. J. Eq. 481, where it was proposed to obstruct light and air over ground dedicated to the public, it is said: "When the strip of land is declared a public highway, the adjoining owner has the right to light and air from it. The column of light and air above the roadbed, whether of |