Meander lines of a river as established by original government survey are not boundary lines unless made so by the instrument of conveyance, the waters themselves constitute the real boundary. Summerville v. Scotts Bluff County, 182 Neb. 311, 154 N.W.2d 517 (1967). See also Hartwig v. Berggren, 179 Neb. 718, 140 N.W.2d 22 (1966).