It was not until the Declaration of Paris in 1856 that general rules of International Law regarding private property on sea came into existence. [Footnote 344: _Robe d'ennemy confisque celle d'amy. Confiscantur ex navibus res, ex rebus naves._] [Footnote 345: Boeck, Nos. 3-103, and Geffcken in Holtzendorff, IV. pp. 572-578, give excellent summaries of the facts.] [Sidenote: Declaration of Paris.] § 177. Things began to undergo a change with the outbreak of the Crimean War in 1854, when all the belligerents proclaimed that they would not issue Letters of Marque, and when, further, Great Britain declared that she would not seize enemy goods on neutral vessels, and when, thirdly, France declared that she would not appropriate neutral goods on enemy vessels. Although this alteration of attitude on the part of the belligerents was originally intended for the Crimean War only and exceptionally, it led after the conclusion of peace in 1856 to the famous and epoch-making Declaration of Paris,[346] which enacted the four rules--(1) that privateering is abolished, (2) that the neutral flag covers enemy goods[347] with the exception of contraband of war, (3) that neutral goods, contraband of war excepted, are not liable to capture under the enemy flag, (4) that blockades, in order to be binding, must be effective, which means maintained by a force sufficient really to prevent access to the coast of the enemy. Since, with the exception of a few States such as the United States of America, Colombia, Venezuela, Bolivia, and Uruguay, all members of the Family of Nations are now parties to the Declaration of Paris, it may well be maintained that the rules quoted are general International Law, the more so as the non-signatory Powers have hitherto in practice always acted in accordance with those rules.[348] [Footnote 346: See Martens, _N.R.G._ XV. p. 767, and above, vol. I. § 559.] [Footnote 347: It has been asserted--see, for instance, Rivier, II. p. 429--that the neutral flag covers only private, not public, enemy property, and therefore that such goods on neutral vessels as belong to the State of the enemy may be seized and appropriated. This opinion would seem, however, to be untenable in face of the fact that the Declaration of Paris speaks of _marchandise neutre_ without any qualification, only excepting contraband goods, thus protecting the whole of the cargo under the neutral flag, contraband excepted. See below, § 319, p. 385, note 3.] [Footnote 348: That there is an agitation for the abolition of the Declaration of Paris has been mentioned above, § 83, p. 100, note 3.] [Sidenote: The Principle of Appropriation of Private Enemy Vessels and Enemy Goods thereon.]