A lateral extension of a main line; a road connected with or issuing from a main line, but not a mere incident of it and not a mere spur or side-track, not one constructed simply to facilitate the business of the chief railway, but designed to have a business of its own in, the transportation of persons and property to and from places not reached by the principal line. Akers y. Canal Co.. 43 X. J. Law, 110; Biles v. Railroad Co., 5 Wash. 509. 32 Pac. 211; Grennan v. McGregor, 78 Cal. 258, 20 Pac. 559; Newhall v. Railroad Co., 14 111. 274; Blanton v. Railroad Co., 86 Va. 618, 10 S. E. 925.