There were active movements in 1852 and 1858, in the South, to revive the African slave trade, and especially was there fierce opposition to the "piracy act." Jefferson Davis, at a convention in Mississippi, July, 1858, advocated the repeal of the latter act, but doubted the practicability then of abrogating the law prohibiting slave traffic.(30) It is worthy of mention here that April 20th, eight days after Sumter was fired upon, Commander Alfred Taylor, commanding the United States naval ship _Saratoga_, in the port of Kabenda, Africa, captured the _Nightingale of Boston_, flying American colors, with a cargo of 961 recently captured, stolen, or purchased African negroes, destined to be carried to some American part and there sold into slavery. This human cargo was sent to the humane Rev. John Seys, at Monrovia, Liberia, to be provided for. One hundred and sixty died on a fourteen-days' sea-voyage, from ship-fever and confinement, though the utmost care was taken by Lieutenant Guthrie and the crew of the slaver for their comfort.(31) The laws abolishing the foreign slave trade and prohibiting the introduction of African slaves (after 1807) into the United States even helped to rivet slavery more firmly therein. They more than doubled the value of a slave, and, therefore, incited slave-breeding to supply the increasing demand in the cotton States, and in time this proved so profitable that the South sought new territory whence slavery could be extended, and out of which slave States could be formed. The "_Declaration against the Slave Trade_" of the world, signed by the representatives of the "Powers" at the Congress of Vienna, in 1815, and repeated at the Congress of Paris at the end of the Napoleonic wars, was potential enough to abate but not to end this most inhuman and sinful trade.(32) Even as late as 1816, English merchants, supported by the corporations of London and Liverpool, through mercantile jealousy, and pretending to believe that the very existence of commerce on the seas and their own existence depended on the continuance of the slave trade, not only opposed the abolition of the black slave traffic, but they opposed the abolition of _white slavery_ in Algiers.(33) This nefarious traffic did not cease in the United States, although at the Treaty of Ghent (1815) it was declared that: "Whereas the traffic in slaves is irreconcilable with the principles of humanity and justice," and the two countries (Great Britain and the United States) therein stipulated to use their best endeavors to abolish it.