THE territory of a State includes the mouths of all rivers, bays, and estuaries, as well as the sea along its coast to the distance of a marine league. This is a regulation dictated by the necessities of self-protection. For the policing of commerce the distance is extended to four leagues; i.e. according to the usage prevailing in Great Britain and the United States, foreign goods coming within that distance cannot be transhipped without the payment of duties.

Vessels belonging to the citizens of any nation on the high seas, and public vessels wherever found, have some of the attributes of territory. If a ship is confiscated on account of piracy or of violation of custom-house laws in a foreign port, or is there attached by the owner's creditor and becomes his property, we never think that territory has been taken away. For a crime committed in port a vessel may be chased into the high seas and there arrested, without a suspicion that territorial rights have been violated, though on the other hand to chase a criminal across the borders and seize him on foreign soil is a gross offence against sovereignty. Yet again, a private vessel, when it arrives in a foreign port, ceases to be regarded as territory, unless treaty provides otherwise, and then becomes merely the property of aliens. The qualities of a private ship which resemble rights of territory are (1), as against its own crew on the high seas (for its own territorial or municipal law accompanies it as long as it is beyond the reach of other law, or until it comes within the bounds of some other jurisdiction), and (2), certain rights as against foreigners, who, on the high seas, are excluded from exercising any form of sovereignty over it, just as they would have been if the vessel in question had actually formed part of the soil of its own country. Public vessels, on the other hand, stand on a higher ground; they are not only public property, as being either built or bought by their Government, but they are, as it were, floating barracks, a part of the public organism, and represent the national dignity, and on this account, even in foreign ports, they are exempt from the local jurisdiction. In both cases, however, it is on account of the crew, rather than on that of the ship itself, that they have any territorial quality. Take the crew away, let the forsaken hulk be met at sea, and it becomes mere abandoned property, and nothing more.

The high sea is now free and open to all nations, but formerly the ocean, or some portions of it, were claimed as a monopoly. Thus the Portuguese prohibited the ships of other nations, and even half-blood subjects of their own race from sailing in the seas of Guinea and the East Indies. " No native-born Portuguese or alien," says one of their ancient ordinances, "shall traverse the lands or seas of Guinea and the Indias, or any territory conquered by us, without license, on pain of death and the loss of all his goods."

So too the Spaniards formerly claimed the right of excluding all others from the Pacific, and it was against such claims, especially against those of the Portuguese, that Grotius, in 1609, wrote his Mare Liberum, in which he lays down the general principle of the free right of navigation, and argues that the sea cannot become property, and that the claims of the Portuguese to the discovery of countries which the ancients have left us an account of, as well as their claims through the donation of Pope Alexander VI., were without foundation. And yet the countrymen of Grotius, who had been the defenders of the liberty of the seas, sought to prevent the Spaniards on their way to the Philippines from taking the route of the Cape of Good Hope. The English, in the seventeenth century, claimed property in the seas surrounding Great Britain, as far as to the coasts of the neighbouring countries, and it was only in the eighteenth that they softened down this claim of property into one of sovereignty. Selden, who published his Mare Clausum in 1635, while contending against the monopolising pretensions of Spain and Portugal, contended zealously, on the ground of ancient precedent for this claim of his country. "The shores and ports of the neighbouring States," said he, "are the limits of the British sea-empire, but in the wide ocean to the north and west the limits are yet to be constituted." Russia finally, at a more recent date, based an exclusive claim to the Pacific, north of the 51st degree, upon the ground that this part of the ocean was a passage to shores lying exclusively within her jurisdiction. But this claim was resisted by the U.S. Government, and withdrawn in a temporary convention of 1824. A treaty of the same empire with this country, made in 1825, contained similar concessions, and at the present day it has come to be generally recognised that the rights of all nations to the use of the high sea being the same, their right to fish upon the high seas, or on banks and shoal places in them are equal. — From Woolsey's International Law.