BLOCKADE. It appears to have been the ancient practice of belligerents at the outset of a war to forbid by proclamation all trade on the part of neutrals with the enemy, and to treat as enemies all those who contravened the proclamation; and neutrals acquiesced tacitly in this practice until the commencement of the 17th century. In the course of that century the ancient practice came into question, as imposing on the commerce of neutrals an in-convenience not justified by any adequate necessity on the part of belligerents, and it has since fallen into desuetude. Belligerents, however, have still maintained, without any question on the part of neutrals, the practice of intercepting supplies going over sea to an enemy under certain conditions, namely, when a belligerent has invested an enemy's port, with the intention of reducing the enemy to surrender from the failure of supplies, and for that object a stoppage of all supplies to such port has become a necessary opera-tion of the war. Any attempt, under such circumstances, on the part of a neutral merchant to introduce supplies into the invested port is a direct interference with the operations of the war, and is inconsistent with neutrality, and it accordingly subjects the offending party to be treated

as an enemy by the belligerent The question, What con-stitutes such a belligerent investment of an enemy's port as to create an obligation on the part of neutrals to abstain from attempting to enter it, has been much controverted since the " armed neutrality" of 1780 ; but all uncertainty as to the principle upon which the decision in each case must proceed, has been put an end to .by the declaration of the powers assembled in congress at Paris in 1856, that " Blockades, in order to be binding, must be effective, that is to say, must be maintained by a force sufficient really to prevent access to the enemy's coast." The question of fact will still be a subject for judicial inquiry in each case of capture, whether the conditions under which a blockade has been maintained satisfy the above declaration. If an asserted blockade is maintained in a manner which satisfies the above declaration, there is no limit to the extent of an enemy's coast which may be placed under blockade. There is also a general consent amongst nations that a neutral merchant must have knowledge of a blockade in order to be liable to be treated as an enemy for attempting to break it; but there is not any uniform practice amongst nations on this subject further than that when a blockade has become notorious, the knowledge of it will be presumed against every neutral vessel which attempts to enter the blockaded port. On the other hand, where a blockade is not notorious, it is in accordance with the practice of nations to give some notice of it to neutrals; and this notice may be communicated to them either by actual warning given to each neutral vessel which seeks to cross the line of blockade, or by a constructive warning to all neutrals resulting from an official notification of the blockade on the part of the blockading power to all powers in amity with it. It is a growing practice, if not altogether an established practice, amongst nations which accredit to one another resident envoys, for belligerents to notify diplomatically to the neutral powers the fact that they have placed an enemy's port under blockade; and it is the rule of the prize courts of Great Britain and of the United States of America to hold that, where such an official notification has been made, all the subjects of the neutral powers may be presumed to have knowledge of the blockade. Other powers, amongst which France may be mentioned, have been accustomed to direct their blockading cruisers to give warning of the blockade to each vessel that attempts to cross the line of blockade, and not to capture any vessel unless she attempts to break the blockade after such warning; but the practice of France agrees with the practice of other powers in not giving such warning after a blockade has become notorious. There is, further, a general practice amongst nations to treat the act of sailing with an intention to enter a blockaded port as an unneutral act, which will warrant the capture of a neutral merchant vessel by a belligerent cruiser on any part of the high seas, unless clear evidence is forthcoming from the captured vessel that the intention has been abandoned, or that its execution was contingent on the blockade being raised. After a port has been placed under blockade, egress is prohibited to all neutral vessels, except to such as have entered the port before the blockade was established, if they come out either in ballast or with cargoes taken on board before the commencement of the blockade. No warning is required to affect such vessel with a knowledge of the blockade, and if any such vessel should succeed in passing through the blockading squadron it becomes liable to capture as good prize by a belligerent cruiser on any part of the high seas, until it has reached its port of destination, when the offence is considered to be purged. Under the ancient practice both ship and cargo were confiscable for the breach of a blockade, and even the captain and crew were liable to be treated as enemies. A milder practice is now generally observed as regards the captain and crew, and a certain equity is administered in the British and American prize courts towards the owners of cargo, where the ship and the cargo do not belong to the same parties, and the owners of the cargo have not any knowledge of the blockade, or have been unable to countermand the shipment of the cargo since the blockade has become known to them. In such cases the cargo is released, although the ship may be rightfully condemned to the captors. (T. T.)