68. ~Action of the Powers from 1814 to 1820.~ At the Congress of Vienna, which assembled late in 1814, Castlereagh was indefatigable in his endeavors to secure the abolition of the trade. France and Spain, however, refused to yield farther than they had already done, and the other powers hesitated to go to the lengths he recommended. Nevertheless, he secured the institution of annual conferences on the matter, and a declaration by the Congress strongly condemning the trade and declaring that "the public voice in all civilized countries was raised to demand its suppression as soon as possible," and that, while the definitive period of termination would be left to subsequent negotiation, the sovereigns would not consider their work done until the trade was entirely suppressed.[19] In the Treaty of Ghent, between Great Britain and the United States, ratified February 17, 1815, Article 10, proposed by Great Britain, declared that, "Whereas the traffic in slaves is irreconcilable with the principles of humanity and justice," the two countries agreed to use their best endeavors in abolishing the trade.[20] The final overthrow of Napoleon was marked by a second declaration of the powers, who, "desiring to give effect to the measures on which they deliberated at the Congress of Vienna, relative to the complete and universal abolition of the Slave Trade, and having, each in their respective Dominions, prohibited without restriction their Colonies and Subjects from taking any part whatever in this Traffic, engage to renew conjointly their efforts, with the view of securing final success to those principles which they proclaimed in the Declaration of the 4th February, 1815, and of concerting, without loss of time, through their Ministers at the Courts of London and of Paris, the most effectual measures for the entire and definitive abolition of a Commerce so odious, and so strongly condemned by the laws of religion and of nature."[21] Treaties further restricting the trade continued to be made by Great Britain: Spain abolished the trade north of the equator in 1817,[22] and promised entire abolition in 1820; Spain, Portugal, and Holland also granted a mutual limited Right of Search to England, and joined in establishing mixed courts.[23] The effort, however, to secure a general declaration of the powers urging, if not compelling, the abolition of the trade in 1820, as well as the attempt to secure a qualified international Right of Visit, failed, although both propositions were strongly urged by England at the Conference of 1818.[24]