The question as to the effects arising from the abuse of the American flag was brought into discussion in 1842, between American and British diplomatists. Great Britain had to acknowledge, as the slave-trade by the United States had only been declared piracy in a municipal sense, that although a vessel was fully equipped for the trade, or even had slaves on board, if American, she was in no sense amenable to British cruisers. It, however, leaves the question unsettled, How is a vessel to be ascertained to be American? The plea that any vessel, hoisting any flag, is thereby secured against all interference in all circumstances, never can be seriously offered as a principle of national law. Neither the United States nor any other power has ever acted on a dogma of this breadth. The United States do not claim that their flag shall give immunity to those who are not American; for such a claim would render it a cover to piracy and to acts of the greatest atrocity. But any vessel which hoists the American flag, claims to be American, and therefore while she may be boarded and examined by an American cruiser, this right is not conceded to a foreign cruiser; for the flag is prima facie evidence, although not conclusive proof of nationality; and if such vessel be really American, the boarding officer will be regarded in the light of a trespasser, and the vessel will have all the protection which that flag supplies. If, on the other hand, the vessel prove not to be American, the flag illegally worn will afford her no protection. Therefore a foreign officer boarding a vessel under the flag of the United States, does it upon his own responsibility for all consequences. These principles have been carried out in the co-operation and joint cruising with British vessels, as will hereafter be seen, with occasional exceptions of blustering and blundering, when American cruisers were absent. This state of things, however, sometimes produces a strange dilemma. The brig “Lawrence,” which was really American, was captured and condemned by an English admiralty court, as a slaver, all of which was contrary to national rights. But it was made out that she was a slaver, and although the master protested, he found himself helpless. The vessel was justly condemned as a slaver, but condemned by the wrong party, which had no legal jurisdiction over her. The master was a pirate if he fell into the hands of American authorities, and thus was debarred all claim for redress. There is no doubt that many such cases occurred, and would again on the withdrawal of the squadron. This, therefore, gave a kind of impunity to the British cruisers, in violating the rights of the American flag, and kept things in an unsound state. The only remedy for it, was in the permanent establishment of an American squadron on the coast.