By this arrangement, as the United States never has consented, and never ought to consent, even on the African coast, to grant to Great Britain, or any other power, the right of search, a slaver, when falling in with an American cruiser, would be prepared to elude search and capture by the display of a foreign ensign and papers, even had she slaves on board. And on the other hand, she might the same day fall in with a British cruiser, and by displaying her flag, and presenting the register or sea-letter, vindicate her American nationality. This illustrates the importance of men-of-war, belonging to each nation, cruising in company for the detection of slavers. Great Britain being in treaty with Spain, Portugal, Brazil, Sardinia and other powers, the proposed mode of co-operation would lead to the detection of slavers under almost any nationality except that of France, which government has an efficient squadron of steamers and sailing vessels on the coast, fully prepared to vindicate her own flag.[6] In reference to vessels ostensibly American, which had been engaged in the slave-trade, a British officer, on the 21st of March, 1850, in a letter inclosing a list of American vessels which had been boarded by the cruiser under his command, stated that all these vessels had afterwards taken slaves from the coast; and with the exception of the “Lucy Ann,”[7] captured with five hundred slaves on board by a British steamer, had escaped. The registers, or sea-letters, of these vessels appeared to be genuine; and he being unable to detect any inaccuracies in their papers, his duty to the American flag had ceased. The vessels in his list had been boarded by himself; but the senior officer of the division was referred to, “who could give a list of many more, all of which would have been good prizes to an officer having the right of search;” for he was well assured that they went over to that coast, fully fitted and equipped for the slave-trade. He expressed a regret that the pleasure of making acquaintance with the commander of the Perry had only fallen to his lot at a moment when the term of his service on the western coast of Africa had expired; but was satisfied that not only on the part of the senior officer commanding the southern division, but also of his brother officers still remaining in service on the coast, the most cordial co-operation would be afforded in the suppression of the slave-trade. The British commissioner, of the mixed commission under the treaty between Great Britain and Portugal for the suppression of the African slave-trade, also furnished a list of suspected slavers which had claimed American nationality. On the 25th of March, the commander requested the English captain to give him a detailed account of the circumstances attending the capture of the barque Navarre, by her B. M. steamer Fire Fly.