§ 172. To the territory of a State belong not only the land within the State boundaries, but also the so-called territorial waters. They consist of the rivers, canals, and lakes which water the land, and, in the case of a State with a seacoast, of the maritime belt and certain gulfs, bays, and straits of the sea. These different kinds of territorial waters will be separately discussed below in §§ 176-197. In contradistinction to these real parts of State territory there are some things that are either in every point or for some part treated as though they were territorial parts of a State. They are fictional and in a sense only parts of the territory. Thus men-of-war and other public vessels on the high seas as well as in foreign territorial waters are essentially in every point treated as though they were floating parts of their home State.[285] And the houses in which foreign diplomatic envoys have their official residence are in many points treated as though they were parts of the home States of the respective envoys.[286] Again, merchantmen on the high seas are for some points treated as though they were floating parts of the territory of the State under whose flag they legitimately sail.[287]
Territorial Subsoil.
§ 173. The subsoil beneath the territorial land and water[288] is of importance on account of telegraph and telephone wires and the like, and further on account of the working of mines and of the building of tunnels. A special part of territory the territorial subsoil is not, although this is frequently asserted. But it is a universally recognised rule of the Law of Nations that the subsoil to an unbounded depth belongs to the State which owns the territory on the surface.
[288] As regards the subsoil of the Open Sea, see below, §§ [287c] and [287d].
Territorial Atmosphere.
§ 174. The space of the territorial atmosphere is no more a special part of territory than the territorial subsoil, but it is of the greatest importance on account of wires for telegraphs, telephones, electric traction, and the like; further on account of wireless telegraphy and of aviation.
(1) Nothing need be said concerning wires for telegraphs and the like, except that obviously the territorial State can prevent neighbouring States from making use of its territorial atmosphere for such wires.