A portion of the sea projecting inland, in which the tide ebbs and flows. 5 Coke, 107. An arm of the sea is considered as extending as far into the interior of a country as the water of fresh rivers is propelled backwards by the ingress of the tide. Ang. Tide- Waters, 73; Hubbard v. Hubbard, 8 N. Y. 196; Adams v. Pease, 2 Conn. 484; U. S. v. Grush, 5 Mason, 290, Fed. Cas. No. 15,268; Ex parte Byers (D. C.) 32 Fed. 404.