It has from time to time been stipulated, in treaties between belligerent and neutral countries, (as in the case of the Treaty between Great Britain and the United States, of 1794,) that vessels of the neutral country should not be considered as having notice of a blockade, until they have been duly and respectfully warned off; and it would only be on a second attempt to enter port that they would be liable to be seized.  Under such a treaty a neutral vessel might lawfully sail for a blockaded port, knowing it to be blockaded.[191]

[Sidenote:  Third Rule of Blockade.]

An act of Violation is essential to a Breach of Blockade; such as, either going in or coming out of the port with a cargo, laden after the commencement of the blockade:  or being found so near to the blockaded port as to show, beyond a doubt, that the vessel was endeavouring to run into it:  or where the intention is expressly avowed by the papers found on board.[192]

The time of shipment is very material; for although it may be hard to refuse a Neutral, liberty to retire with a cargo already laden, and by that act already become neutral property,—­yet, after the commencement of a blockade, a neutral cannot be allowed to interpose in any way to assist the exportation of the property of the enemy.  After the commencement of a blockade, a Neutral is no longer at liberty to make any purchase in that port.[193]

A Maritime Blockade is not in law violated by bringing or sending goods to the port through the internal canal navigation or land carriage of the country; and thus such goods are not liable to confiscation on ground of the blockade.

[Sidenote:  Right of Search.]

On the great question of the Right of Search, the International Law has been summed up by Lord Stowell, in the case of the Maria, where the exercise of the right was attempted to be resisted, by the interposition of a convoy of Swedish ships of war.[194]

First, the right of visiting and searching merchant ships on the high seas, whatever be the ships, whatever be the cargoes, whatever be the destinations, is the incontestible right of the lawfully commissioned cruizers of a belligerent nation.

Secondly, that the authority of the Sovran of the neutral country, being interposed in any manner of mere force, cannot legally vary the rights of a lawfully commissioned belligerent cruizer.  It cannot be maintained, that if a Swedish commissioned cruizer, during the wars of his own country, has a right, by the Laws of Nations, to visit and examine neutral ships, the King of England, (being Neutral to Sweden,) is authorized by law to obstruct the exercise of that right with respect to the merchants’ ships of his country.

Thirdly, that the penalty for the violent contravention of this right, is the confiscation of the property withheld from visitation and search.

The judgment of condemnation, pronounced in this case, was followed by the Treaty of Armed Neutrality entered into by the Baltic Powers to resist the Right of Search, in 1800, which league was dissolved by the death of the Emperor Paul, and the points in controversy between those Powers and Great Britain were finally adjusted by the Convention of 5th of June, 1805.[195]