HIGH SEAS, an expression in international law meaning all those parts of the sea not under the sovereignty of adjacent states. Claims have at times been made to exclusive dominion over large areas of the sea as well as over wide margins, such as a 100 m., 60 m., range of vision, &c., from land. The action and reaction of the interests of navigation, however, have brought states to adopt a limitation first enunciated by Bynkershoek in the formula "terrae dominium finitur ubi finitur armorum vis." Thenceforward cannon-shot range became the determining factor in the fixation of the margin of sea afterwards known as "territorial waters" (q.v.). With the exception of these territorial waters, bays of certain dimensions and inland waters surrounded by territory of the same state, and serving only as a means of access to ports of the state by whose territory they are surrounded, and some waters allowed by immemorial usage to rank as territorial, all seas and oceans form part of the high sea. The usage of the high sea is free to all the nations of the world, subject only to such restrictions as result from respect for the equal rights of others, and to those which nations may contract with each other to observe. An interesting case affecting land-locked seas was that of the _Emperor of Japan_ v. _The Peninsular and Oriental Steam Navigation Company_, in which a collision had taken place in the inland sea of Japan. The British Supreme Court at Shanghai declared this sea to form part of the high sea. On appeal to the privy council, the appellants were successful. Though the decision of the Shanghai court on the point in question was not dealt with by the privy council, Japan continues to treat her inland sea as under her exclusive jurisdiction. (T. Ba.)