Not inferior in importance and delicacy to the other subjects provided for by the treaty was that which concerned the measures for the suppression of "the slave-trade" on the coast of Africa. In order to understand the difficulties with which Mr. Webster had to contend on this subject, a brief history of the question must be given. The law of nations, as understood and expounded by the most respectable authorities and tribunals, European and American, recognizes the right of search of neutral vessels in time of war, by the public ships of the belligerents. It recognizes no right of search in time of peace. It makes no distinction between a right of visitation and a right of search. To compel a trading-vessel, against the will of her commander, to come to and be boarded, for any purpose whatsoever, is an exercise of the right of search which the law of nations concedes to belligerents for certain purposes. To do this in time of peace, under whatever name it may be excused or justified, is to perform an act of mere power, for which the law of nations affords no warrant. The moral quality of the action, and the estimate formed of it, will of course depend upon circumstances, motives, and manner. If an armed ship board a vessel under reasonable suspicion that she is a pirate, and when there is no other convenient mode of ascertaining that point, there would be no cause of blame, although the suspicion turned out to be groundless. The British government, for the praiseworthy purpose of putting a stop to the traffic in slaves, has at different times entered into conventions with several of the states of Europe authorizing a mutual right of search of the trading-vessels of each contracting party by the armed cruisers of the other party. These treaties give no right to search the vessels of nations not parties to them. But if an armed ship of either party should search a vessel of a third power under a reasonable suspicion that she belonged to the other contracting party, and was pursuing the slave-trade in contravention of the treaty, this act of power, performed by mistake, and with requisite moderation and circumspection in the manner, would not be just ground of offence. It would, however, authorize a reasonable expectation of indemnification on behalf of the private individuals who might suffer by the detention, as in other cases of injury inflicted on innocent persons by public functionaries acting with good intentions, but at their peril.