object. The division of the islands in the river and its bays would follow the same rule.1

24. Where the dividing line of two States is water, as a river or lake, which is subject to changes, important questions may arise respecting the rights of property. Thus, where, by a gradual and insensible movement, the water ad. vances on one side and recedes on the other, or by detrition on one side and deposit on the other, a portion of the soil is gradually transferred, there is evidently a loss to one State and an increase to the other. So also, where islands are washed away on one side of the channel, and new ones formed on the other, there is a corresponding change of territory. Again, suppose that the river or lake which constitutes the boundary has suddenly changed its bed, will this change produce a corresponding increase or diminution of territory to the adjacent proprietors? The Roman law determined with great care the effects of changes in the distribution of waters upon the ownership of private lands; and the influence of this law is manifest in the rules adopted by publicists with respect to international property.2

§ 25. Where the moving of the dividing water is so gradual as to be almost insensible, the changes produced are not considered as acquisitions and losses of property, but the natural consequences of property already existing; because, the thing owned is naturally susceptible of this physical increase or decrease. In such a case, whether the dividing water belongs entirely to one State, or the boundary is the middle or Thalweg, each party gains or loses accordingly as the increase or decrease is upon its side. The same rule applies to the gradual removal or formation of islands in a river or lake which divides States, or in the sea, within the territorial limits or ligne de respect of a State bordering upon the ocean. More

1 Gundling, Jus. Nat., p. 248; Wolfius, Jus Gentium, §§ 106-109; Stypmannus, Jus Marit., etc. cap. v. n. 476-552; Merlin, Répertoire, voc. 'alluvium ;' Rayneval, Droit de la Nature, tome i. p. 307; De Cussy, Droit Maritime, liv. i. tit. ii. § 57.

2 Rayneval, Inst. du Droit Nat. liv. ii. ch. xi.; Pothier, Euvres de, tome x. pp. 87, 88; Voet, ad Pandects, tome i. pp. 606, 607; Heineccius, Revitaciones, lib. ii. tit. i. §§ 356-369; Las Siete Partidas, part. iii. tit. xxviii. 1. xxxi. ; Alvarez, Institutes, lib. ii. tit. i. § 6; Asso, Instituciones, p. 101; Gomez, Elementos, lib. ii. tit. iv. § 3; Febrero Mexicana, tome i p. 161; Sala Mexicana, tomo ii. p. 62; Justinian, Inst., lib. ii. tit. i. §§ 20-24; De Camps, Manuel des Prop. Riv. passim; Chardon, Droit a'Alluvion, passim.

over, a State has a certain right of preemption to islands formed adjacent to its coast, even outside of this line of respect. But the case is very different where the river abandons its ancient bed and forms a new channel, or where a lake leaves its former banks and forms a new lake, or a series of new lakes; the boundaries of the States remain in the abandoned bed of the river, or in the position formerly occupied by the lake.'

§ 26. Where a navigable river, during a part of its course, flows through the territory or forms the boundary of one State, but passes through a third State before it enters the sea, questions of some difficulty have arisen with respect to its dominion and use. It is, however, now generally conceded that the right of navigation, for commercial purposes, is common to all the nations inhabiting the different parts of its banks. But this right of innocent passage, being what the text-writers call an imperfect right, its exercise is necessarily modified by the safety and convenience of the State which is affected by it, and can only be effectually secured by mutual conventions, regulating the mode of its exercise. In other words, the outlet of the river being entirely within the territorial jurisdiction of one State, that State may establish and enforce all proper and necessary regulations, so that this right of innocent passage shall neither endanger its own safety nor interfere with its own paramount right of legislation and jurisdiction. The Roman law declared navigable rivers to be so far public property that a free passage over them was open to everybody, but distinguished between rivers and the sea, the former being classed among res publicæ, and the latter among res communes.2

1 Grotius, De Jur. Bel. ac Pac., lib. vii. cap. iii. § 17; Ortolan Domaine International, §§ 85-93; Heffter, Droit International, § 69 note; Gunther, Europ. Völkerrecht, t. ii. p. 57; Pestel, Commentarii de Repub. Batav. § 268; Bowyer, Universal Public Law, ch. xxviii.; Riquelme, Derecho Pub. Int., lib. i. tit. i. cap. iv.; Bello, Derecho Internacional, pt. i. cap. iii.; Pando, Derecho Internacional, p. 99; Almeda, Derecho Publico, tome i. p. 199; Cushing, Opinions U. S. Attys. Genl., vol. viii. p. 175; Crittenden, Opinions U. S. Att'ys. Genl., vol. v. pp. 264, 412; Puffendorf, De Jur. Nat. et Gent., lib. iv. cap. v. § 8; Wolfius, Jus Gentium, §§ 108, 109; Proudhon et Dumay, Domaine Public, tome iv. ch. lvi. sec. 7.

2 Justinian, Institutes, lib. ii. tit. i. §§ 1, 2; Phillimore, On Int. Law, vol. i. §§ 155-6; Vattel, Droit des Gens, liv. ii. ch. ix. §§ 126-130; ch. x. §§ 132-134; Puffendorf, De Jur. Nat. et Gent., lib. iii. cap. iii. §§ 3-6; Polson, Law of Nations, sec. v.

§ 27. The Roman law also declares the right to use the shores to be an incident to that of the water, and the right to navigate a river carries with it the right to moor vessels to its banks, to lade and unlade cargoes, &c. Publicists have applied this principle of the Roman civil law to the same case between nations, and infer the right to use the adjacent land for the purposes, as means necessary to the attainment of the end for which the free navigation of the water is permitted. The principal right would seem to draw after it the incidental right of using all the means which are necessary to secure its proper enjoyment. But this incidental right, like the principal right itself, is imperfect in its nature, and the mutual convenience of both parties must be consulted in its exercise.'

§ 28. Such right of innocent passage, though an imperfect right, and requiring mutual conventions regulating the mode of its exercise, is nevertheless a real, subsisting right, founded upon the law of nature, and recognised by the most approved writers on public law. It may also be added that it has been recognised by the general consent of nations, and must now be regarded as an established principle of international law.2

§ 29. But those interested in the enjoyment of this principal right, and its incidents, may renounce them entirely, or consent to modify them in such a manner as mutual convenience and policy may dictate. Thus, by the treaty of Westphalia, the navigation of the river Scheldt was closed to the Belgic provinces, in favour of the Dutch; and by the treaties of Vienna, and subsequent conventions, the ripuarian powers, on the banks of the great rivers of Europe, agreed to certain detailed regulations respecting their navigation through the territory of the States in which such rivers débouched into the ocean. But this agreement of the ripuarian States to regulations of police and fixed toll duties on vessels and merchandise passing through the territory of another State, to and from the sea, or even an entire surrender or renouncement of the right, cannot be adduced as an argument against the existence of the right itself. On the contrary, if no such right existed, there would be no necessity for its

1 Wheaton, Elem. Int. Law, pt. ii. ch. iv. §1 3.

2 Grotius, De Fur. Bel. ac Pac., lib. ii. cap. iii. §§ 7-12; Heffter, Droit International, §§ 77-80.

regulation, and its renouncement would be an act of supererogation.'

30. The navigation of the Rhine has often afforded matters of difficulty and dispute between the States which border on it, or through whose territories it flows. By Annexe sixteen to the final act of the congress of Vienna, in 1815, the free navigation of this river was confirmed in its whole course, from the point where it becomes navigable to the sea, ascending and descending.' The interpretation of these stipulations gave rise to a controversy between the kingdom of the Netherlands and other States interested in the navigation of that river, from the fact that the Rhine, properly so called, does not empty into the sea, but loses its waters among the sandy downs at Kulwick, the navigation being carried on, through the mouths or arms of the sea called the Leck, the Yssel, and the Waal and Meuse. After a long and tedious negotiation, the question was finally settled by the convention of Mayence in 1841, providing for the free navigation and commerce of the ripuarian States 'into the sea,' with minute regulations of police, and fixed toll duties on vessels and merchandise passing to and from the sea, and to the ports of the upper ripuarian States on the Rhine.2

§ 31. The same principle was extended in 1815, by the congress of Vienna, to the navigation of the Neckar, the Mayn, the Moselle, the Meuse, and the Scheldt; and similar provisions were made for the free navigation of the Elbe in 1821, and, at other periods, of the Po, the Danube, the Vistula and other rivers of ancient Poland. The treaty

of Westphalia, 1648, by which the independence of the United Provinces was acknowledged by Spain, contained a stipulation by which the river Scheldt was to continue shut on the side of the former, who were proprietors of both banks, toward the sea. It was also stipulated that the inhabitants of the United Provinces should abstain from frequenting the places occupied by Spain in the East Indies. Another motive alleged by the Dutch for this stipulation, closing the navigation of the lower Scheldt, was, that the whole course of the two branches of this river, which passed within the domi

1 Wheaton, Hist. Law of Nations, pp. 282-4, 552.

2 Martens, Nouveau Recueil, tome ix. p. 252; Ortolan, Domaine International, § 44.

nions of Holland, was entirely artificial; that it owed its existence to the skill and labour of Dutchmen; that its banks had been erected and maintained by them at great expense. The emperor Joseph II., in 1781, attempted to open the navigation of this river, and for this purpose, in 1784, brought forward several antiquated claims against the republic. A compromise was effected by the treaty of Fontainebleau, in 1785, by which it was agreed that the river Scheldt, from Saftingen to the sea, should continue to be shut on the side of the States General, as well as the canals of Sas, Swin, and the other mouths of the sea there terminating, conformably to the treaty of Munster. In return for these concessions, the Dutch accorded several of the emperor's demands, and agreed to pay an indemnity of ten millions of florins. The claim of Holland in this discussion was defended by Mirabeau, on the ground of positive conventional law. He was not absolutely opposed to the free navigation of the Scheldt, but, on the contrary, endeavoured to show how it might be opened without danger to Holland and Europe, by the independence of Belgium, which would form a neutral barrier to the United Provinces. The free navigation of this river was again seriously discussed in 1792-3, in the diplomatic correspondence between Holland, Belgium, England and France; and the question finally settled, as before stated, by the congress of Vienna, in 1815, on the basis of the celebrated memoir presented by Baron Wilhelm Von Humboldt.1

32. By the treaty of 1763, between France, Spain, and Great Britain, the boundary between the French and British possessions in North America was the middle of the river Mississippi, from its source to the Iberville, and thence, through that river and lakes Maurepas and Pontchartrain, to the sea. The right of freely navigating the Mississippi, from its source to the sea, was, at the same time, secured to the subjects of Great Britain. Both Louisiana and Florida were afterwards ceded to Spain by France and Great Britain. By the independence of the United States, its citizens had acquired the same rights, with respect to the navigation of the Mississippi, as had belonged to the subjects of Great Britain. But Spain, having become possessed of both banks of that river, from

1 Martens, Rec. de Traités, tome xxx. p. 209; Mayer, Corpus Juris Germ., tome ii. pp. 224-239, 298; De Cussy, Droit Maritime, liv. i. tit. ii. § 57; lib. ii. ch. xxviii.