This appears to have been the only effort made by the European powers in concert, to enforce the observance by the Barbary States of the principles which regulate intercourse and warfare among more civilized nations; the Governments of Britain and France however, as we shall see, continued separately to maintain those principles; of the other powers each acted for itself, paying, threatening or fighting, as it conceived most proper for its own interests and honor. In 1812 and 1823, when the insurrection of the Greeks had already assumed so formidable a character, as to require the utmost exertions on the part of the Sultan, each of the Barbary States sent ships to his aid; on this occasion, the Government of Great Britain exacted from the Bey of Tunis a declaration that the Greeks who might be taken by his forces should not be enslaved, but be treated as prisoners of war. No such promise appears recorded on the part of the Dey of Algiers, and the propriety of requiring it for the interests of humanity, may be doubted; a powerful incentive to the continuance of the war against the Greeks would indeed be thus removed; but on the other hand, it might have been supposed that little mercy would be shown to captives who if preserved were to be supported at an expense, while nothing was to be obtained from their labor or for their ransom. This supposition is strengthened by the fact, that an Algerine Ambassador who was sent to London in 1819, propounded to the Secretary for Foreign Affairs the question--"Whether, as his Government had engaged to make no Christian slaves, its cruisers might without offending Great Britain, put to death those of their prisoners whom by treaty they could not reduce to slavery?" The Algerines sent eight ships to the Archipelago, which returned in the autumn of 1823; how they conducted themselves in the war it is not easy to ascertain; the Dey chose to consider that they had acquired a title to immortal renown, and while elated by their real or fancied successes, he ventured to commit an act of violence against the British Consul, which caused Algiers to undergo another humiliation.