International Law. A Treatise Volume Ii Part 53

(1) There must be a _declaration_ as well as a _notification_ in order to make a blockade binding (article 8). If there is either no proper declaration or no proper notification, the blockade is not binding.

(2) A _declaration_ of blockade is made either by the blockading Power or by the naval authorities acting in its name. The declaration of blockade must specify (_a_) the date when the blockade begins; (_b_) the geographical limits of the coastline under blockade; and (_c_) the period within which neutral vessels may come out (article 9). If the commencement of the blockade or its geographical limits are given inaccurately in the declaration, or if no mention is made of the period within which neutral vessels may come out, or if this period is given inaccurately, the declaration is void, and a new declaration is necessary in order to make the blockade binding (article 10).

(3) _Notification_ of the declaration of blockade must at once be made.

Two notifications are necessary (article 11):--

The first notification must be made by the Government of the blockading fleet to all neutral Governments either through the diplomatic channel, or otherwise, for instance by telegraph. The purpose of this notification is to enable neutral Governments to inform merchantmen sailing under their flag of the establishment of a blockade.

The second notification must be made to the local authorities by the officer commanding the blockading force; these authorities have on their part to notify, as soon as possible, the foreign consuls at the blockaded port or coastline. The purpose of this notification is to enable neutral merchantmen in the blockaded port or ports to receive knowledge of the establishment of the blockade and to prepare themselves to leave the port within the period specified in the declaration of blockade.

(4) The rules as to declaration and notification of blockade apply to cases where the limits of a blockade have been extended, or where a blockade is re-established after having been raised (article 12).

[Sidenote: Length of Time for Egress of Neutral Vessels.]

-- 377. As regards _ingress_, a blockade becomes valid the moment it is established; even vessels in ballast have no right of ingress. As regards _egress_, it has always been usual for the blockading commander to grant a certain length of time within which neutral vessels might leave the blockaded ports unhindered, but no rule existed respecting the length of such time, although fifteen days were frequently granted.[756] This usage of granting to neutral vessels a period within which they may leave the blockaded port, has been made a binding rule by the Declaration of London. For, since article 9 enacts that a declaration of blockade must specify the period within which neutral vessels may come out, it implicitly enacts that the granting of such a period is compulsory, although it may only be long enough to enable neutral vessels to make their way out as quickly as possible.

[Footnote 756: According to U.S. Naval War Code, article 43, thirty days are allowed "unless otherwise specially ordered."]

[Sidenote: End of Blockade.]

-- 378. Apart from the conclusion of peace, a blockade can come to an end in three different ways.

It may, firstly, be raised, or restricted in its limits, by the blockading Power for any reason it likes. In such a case it has always been usual to notify the end of blockade to all neutral maritime States, and article 13 of the Declaration of London turns this usage into a binding rule by enacting that the voluntary raising of a blockade, as also any restrictions in its limits, must, in the same way as the declaration of a blockade, be notified to all neutral Governments by the blockading Power, as well as to the local authorities by the officer commanding the blockading fleet.

A blockade can, secondly, come to an end through an enemy force driving off the blockading squadron or fleet. In such case the blockade ends _ipso facto_ by the blockading squadron being driven away, whatever their intention as to returning may be. Should the squadron return and resume the blockade, it must be considered as new, and not simply the continuation of the former blockade, and another declaration and notification are necessary (article 12 of the Declaration of London).

The third ground for the ending of a blockade is its failure to be effective, a point which will be treated below in -- 382.

III

EFFECTIVENESS OF BLOCKADE

See the literature quoted above at the commencement of -- 368.

[Sidenote: Effective in contradistinction to Fict.i.tious Blockade.]

-- 379. The necessity for effectiveness in a blockade by means of the presence of a blockading squadron of sufficient strength to prevent egress and ingress of vessels became gradually recognised during the first half of the nineteenth century; it became formally enacted as a principle of the Law of Nations through the Declaration of Paris in 1856, and the Declaration of London enacts it by article 2. Effective blockade is the contrast to so-called fict.i.tious or paper blockade, which was frequently practised during the seventeenth, eighteenth, and at the beginning of the nineteenth century.[757] Fict.i.tious blockade consists in the declaration and notification that a port or a coast is blockaded without, however, posting a sufficient number of men-of-war on the spot to be really able to prevent egress and ingress of every vessel. It was one of the principles of the First and of the Second Armed Neutrality that a blockade should always be effective, but it was not till after the Napoleonic wars that this principle gradually found universal recognition. During the second half of the nineteenth century even those States which had not acceded to the Declaration of Paris did not dissent regarding the necessity for effectiveness of blockade.

[Footnote 757: See Fauchille, _Blocus_, pp. 74-109.]

[Sidenote: Condition of Effectiveness of Blockade.]

-- 380. The condition of effectiveness of blockade, as defined by the Declaration of Paris, is its maintenance _by such a force as is sufficient really to prevent access to the coast_. But no unanimity exists respecting what is required to const.i.tute an effective blockade according to this definition. Apart from differences of opinion regarding points of minor interest, it may be stated that in the main there are two conflicting opinions.

According to one opinion, the definition of an effective blockade p.r.o.nounced by the First Armed Neutrality of 1780 is valid, and a blockade is effective only when the approach to the coast is barred by a chain of men-of-war anch.o.r.ed on the spot and so near to one another that the line cannot be pa.s.sed without obvious danger to the pa.s.sing vessel.[758] This corresponds to the practice hitherto followed by France.

[Footnote 758: See Hautefeuille, II. p. 194; Gessner, p. 179; Kleen, I.

-- 129; Boeck, Nos. 676-681; Dupuis, Nos. 173-174; Fauchille, _Blocus_, pp. 110-142. Phillimore, III. -- 293, takes up the same standpoint in so far as a blockade _de facto_ is concerned:--"A blockade _de facto_ should be effected by stationing a number of ships, and forming as it were an arch of circ.u.mvallation round the mouth of the prohibited port, where, if the arch fails in any one part, the blockade itself fails altogether."]

According to another opinion, a blockade is effective when the approach is watched--to use the words of Dr. Lushington[759]--"by a force sufficient to render the egress and ingress dangerous, or, in other words, save under peculiar circ.u.mstances, as fogs, violent winds, and some necessary absences, sufficient to render the capture of vessels attempting to go in or come out most probable." According to this opinion there need be no chain of anch.o.r.ed men-of-war to expose any vessels attempting to break the blockade to a cross fire, but a real danger of capture suffices, whether the danger is caused by cruising or anch.o.r.ed men-of-war. This is the standpoint of theory and practice of Great Britain and the United States, and it seems likewise to be that of Germany and several German writers.[760] The blockade during the American War of the whole coast of the Confederate States to the extent of 2500 nautical miles by four hundred Federal cruisers could, of course, only be maintained by cruising vessels; and the fact that all neutral maritime States recognised it as effective shows that the opinion of dissenting writers has more theoretical than practical importance.

[Footnote 759: In his judgment in the case of the _Franciska_ (1855), Spinks, 287.]

[Footnote 760: See Perels, -- 49; Bluntschli, -- 829; Liszt, -- 41, III.]

The Declaration of London has settled the controversy in so far as article 3 enacts that "the question whether a blockade is effective, is a question of fact." Each case must, therefore, be judged according to its merits, and the before mentioned decision of Dr. Lushington would seem to have found implied recognition by article 3.

The question of effectiveness being one of fact, and the real danger to pa.s.sing vessels being the characteristic of effectiveness of blockade, it must be recognised that in certain cases and in the absence of a sufficient number of men-of-war a blockade may be made effective through planting land batteries within range of any vessel attempting to pa.s.s,[761] provided there be at least one man-of-war on the spot. But a stone blockade,[762] so called because vessels laden with stones are sunk in the channel to block the approach, is not an effective blockade.

[Footnote 761: The _Nancy_ (1809), 1 Acton, 63; the _Circa.s.sian_ (1864), 2 Wallace, 135; the _Olinde Rodrigues_ (1898), 174, United States, 510.

See also Bluntschli, -- 829; Perels, -- 49; Geffcken in Holtzendorff, IV.

p. 750; Walker, _Manual_, -- 78.]

[Footnote 762: See above, -- 368, p. 450, note 1. It ought to be mentioned here also that according to article 2 of Convention VIII. "it is forbidden to lay automatic contact mines off the ports and coasts of the enemy, with the sole object of intercepting commercial navigation."]

And it must, lastly, be mentioned that the distance of the blockading men-of war from the blockaded port or coast is immaterial so long as the circ.u.mstances and conditions of the special case justify such distance.

Thus during the Crimean War the port of Riga was blockaded by a man-of-war stationed at a distance of 120 miles from the town, in the Lyser Ort, a channel three miles wide forming the only approach to the gulf.[763]

[Footnote 763: The _Franciska_ (1855), Spinks, 287. See Hall, -- 260, and Holland, _Studies_, pp. 166-167.]

[Sidenote: Amount of Danger which creates Effectiveness.]

-- 381. It is impossible to state exactly what degree of danger to a vessel attempting to pa.s.s is necessary to prove an effective blockade.

It is recognised that a blockade does not cease to be effective in case now and then a vessel succeeds in pa.s.sing the line unhindered, provided there was so much danger as to make her capture probable. Dr. Lushington strikingly dealt with the matter in the following words:[764]--"The maintenance of a blockade must always be a question of degree--of the degree of danger attending ships going into or leaving a port. Nothing is further from my intention, nor indeed more opposed to my notions, than any relaxation of the rule that a blockade must be sufficiently maintained; but it is perfectly obvious that no force could bar the entrance to absolute certainty; that vessels may get in and get out during the night, or fogs, or violent winds, or occasional absence; that it is most difficult to judge from numbers alone. Hence, I believe that in every case the inquiry has been, whether the force was competent and present, and, if so, the performance of the duty was presumed; and I think I may safely a.s.sert that in no case was a blockade held to be void when the blockading force was on the spot or near thereto on the ground of vessels entering into or escaping from the port, where such ingress or egress did not take place with the consent of the blockading squadron."

[Footnote 764: In his judgment in the case of the _Franciska_ (1855), Spinks, 287.]

[Sidenote: Cessation of Effectiveness.]

-- 382. A blockade is effective so long as the danger lasts which makes probable the capture of such vessels as attempt to pa.s.s the approach. A blockade, therefore, ceases _ipso facto_ by the absence of such danger, whether the blockading men-of-war are driven away, or are sent away for the fulfilment of some task which has nothing to do with the blockade, or voluntarily withdraw, or allow the pa.s.sage of vessels in other cases than those which are exceptionally admissible. Thus, when in 1861, during the American Civil War, the Federal cruiser _Niagara_, which blockaded Charleston, was sent away and her place was taken after five days by the _Minnesota_, the blockade ceased to be effective, although the Federal Government refused to recognise this.[765] Thus, further, when during the Crimean War Great Britain allowed Russian vessels to export goods from blockaded ports, and accordingly the egress of such vessels from the blockaded port of Riga was permitted, the blockade of Riga ceased to be effective, because it tried to interfere with neutral commerce only; therefore, the capture of the Danish vessel _Franciska_[766] for attempting to break the blockade was not upheld.

[Footnote 765: See Mountague Bernard, _Neutrality of Great Britain during the American Civil War_ (1870), pp. 237-239.]

[Footnote 766: Spinks, 287. See above, -- 370.]

On the other hand, practice[767] and the majority of writers have always recognised the fact that a blockade does not cease to be effective in case the blockading force is driven away for a short time through stress of weather, and article 4 of the Declaration of London precisely enacts that "a blockade is not regarded as raised if the blockading force is temporarily withdrawn on account of stress of weather." English[768]

writers, further, have hitherto denied that a blockade loses effectiveness through a blockading man-of-war being absent for a short time for the purpose of chasing a vessel which succeeded in pa.s.sing the approach unhindered,[769] but the Declaration of London does not recognise this.[770]

[Footnote 767: The _Columbia_ (1799), 1 C. Rob. 154.]

[Footnote 768: See Twiss, II. -- 103, p. 201, and Phillimore, III. -- 294.]

[Footnote 769: See article 37 of U.S. Naval War Code.]

[Footnote 770: See the Report of the Drafting Committee on article 4 of the Declaration of London.]

IV