A structure erected over a river, creek, stream, ditch, ravine, or other place to facilitate the passage thereof; in- cluding by the term both arches and abut- ments. 3 Harr. N. J. 108; 15 Vt. 438; 55 Ga. 609. A railway viaduct, designed only for the passage of engines and cars, is not a "bridge," within the statutory mean- ing of that word; 1 Wall. 116. See 7 Nev. 294; 40 Ν. J. L. 805. Bridges are either public or private. Public bridges are such as form a part of the highway, common, according to their character as foot, horse, or carriage bridges, to the public generally, with or without toll; 2 East 342; though their use may be limited to particular occasions, as to seasons of flood or frost: 2 Maule & S. 262: 4 Campb. 189. They are established either by legislative authority or by dedication. By legislative authority. By the Great Charter (9 Hen. III. c. 15), in England, no town or freeman can be compelled to make new bridges where never any were before, but by act of parliament. Under such act, they may be erected and maintained by corporations chartered for the purpose, or by counties, or in whatever other mode may be prescribed; Woolrych, Ways 196. In this country it is the practice to charter companies for the same purpose, with the right to take tolls for their reimbursement; 4 Pick. 341; or to erect bridges at the state's expense; or by general statutes to impose the duty of erection and main- tenance upon towns, counties, or districts; 2 W. & S. 495; 5 Gratt. 241; 2 Ohio 508; 23 Conn. 416; 14 B. Monr. 92; 5 Cal. 426; 1 Mass. 153; 12 N. Y. 52; 2 N. H. 513; 59 Me. 80; 85 Pa. 163; 78 id. 457; 47 N. J. Law 89. For their erection the state may take private property, upon making com- pensation, as in case of other highways; Ang. Highw. §81; the rule of damages for land so taken being not its mere value for agricultural purposes, but its value for a bridge site, minus the benefits derived to the owner from the erection: 17 Ga. 30. The right to erect a bridge upon the land of another may also be acquired by mere parol license, which, when acted upon, becomes ir- revocable; 11 Ν. Η. 102; 14 Ga. 1. But see 4 R. I. 47. The franchise of a toll bridge or ferry may be taken, like other property, for a free bridge; 6 How. 507; 23 Pick. 360; 4 Gray 474; 28 N. H. 195; and, when vested in a town or other public corpora- tion, may be so taken without compensa- tion; 10 How. 511. A new bridge may be erected, under legis- lative authority, so near an older bridge or ferry as to impair or destroy its value, without compensation, unless the older franchise be protected by the terms of its grant; 11 Pet. 420; 7 Pick. 344; 6 Paige, Ch. 554; 1 Barb. Ch. 547; 3 Sandf. Ch. 625; 8 Bush 31; 2 Dill. 332; 21 Can. S. C. R. 456; 3 Wall. 51; but, unless authorized by statute, a new bridge so erected is unlaw- ful, and may be enjoined as a nuisance; 3 Bla. Com. 218, 219; 4 Term 566; 2 Cr. M. & R. 432; 6 Cal. 590; 3 Wend. 610; 8 Ala. 211; 11 Pet. 261, Story, J.; and if the older franchise, vested in an individual or private corporation, be protected, or be exclusive within given limits, by the terms of its grant, the erection of a new bridge or ferry, even under legislative authority, is unconstitutional, as an act impairing the obligations of contract; 7 N. H. 35; 17 Conn. 40; 10 Ala. N. S. 37. See 21 Can. S. C. R. 456. The entire expense of a bridge erected within a particular town or district may be assessed upon the inhabit- ants of such town or district; 10 Ill. 405; 23 Conn. 416. The absolute control of navigable streams in the United States is vested in congress; Miller, Const. U. S. 457; but in the absence of legislation by congress a state has the right to erect a bridge over a navigable river within its own limits; 3 Wall. 718; 4 Pick. 460; 1 Ν. H. 467; 5 McL. 425; 35 Me. 325; 22 Conn. 198; 27 Pa. 303; 15 Wend. 113; and so may a county; 12 Pa. Co. Ct. R. 669; al- though in exercising this right, care must be taken to interrupt navigation as little as possible; 43 Me. 198; 3 Hill 621; 23 Eng. L. & Eq. 240; 4 Harr. Del. 544; 4 Ind. 36; 2 Gray 339; 6 McL. 70, 209. The erection of a bridge entirely within a state across a navigable river running partly within and partly without the state is not a matter so directly connected with interstate commerce as to be under the exclusive control of congress, and in the absence of congressional action the state has authority to regulate the same; 53 Fed. Rep. 16. A state has no power to fix tolls on a bridge connecting it with another state, thereby regulating charges on interstate commerce without the consent of con- gress or the concurrence of such other state. The chief justice and three as- sociate justices concurred on the ground that concurrent acts of the state incor- porating the bridge company and authoriz- ing it to fix tolls constituted a contract between the corporation and both states which could not be altered by one state without the consent of the other; 154 U. S. 204, 2