ANOTHER question, "How shall the slave trade be suppressed?" began to be agitated near the close of the last century. The moral desolation existing in Africa, was without a parallel among the nations of the earth. When the last of our Northern States had freed its slaves, not a single Christian Church had been successfully established in Africa, and the slave trade was still legalized to the citizens of every Christian nation. Even its subsequent prohibition, by the United States and England, had no tendency to check the traffic, nor ameliorate the condition of the African. The other Europeon powers, having now the monopoly of the trade, continued to prosecute it with a vigor it never felt before. The institution of slavery, while lessened in the United States, where it had not yet been made profitable, was rapidly acquiring an unprecedented enlargement in Cuba and Brazil, where its profitable character had been more fully realized. How shall the slave trade be annihilated, slavery extension prevented, and Africa receive a Christian civilization? were questions that agitated the bosom of many a philanthropist, long after Wilberforce had achieved his triumphs. It was found, that the passage of laws prohibiting the slave trade, and the extermination of that traffic, were two distinct things--the one not necessarily following the other. The success of Wilberforce with the British Parliament, only increased the necessity for additional philanthropic efforts; and a quarter of a century afterwards found the evil vastly increased which he imagined was wholly destroyed. It was at the period in the history of Africa, and of public sentiment on slavery, which we have been considering, that the American Colonization Society was organized. It began its labors when the eye of the statesman, the philanthropist, and the Christian, could discover no other plan of overcoming the moral desolation, the universal oppression of the colored race, than by restoring the most enlightened of their number to Africa itself. Emancipation, by States, had been at an end for a dozen of years. The improvement of the free colored people, in the presence of the slave, was considered impracticable. Slave labor had become so profitable, as to leave little ground to expect general emancipation, even though all other objections had been removed. The slave trade had increased twenty-five per cent. during the preceding ten years. Slavery was rapidly extending itself in the tropics, and could not be arrested but by the suppression of the slave trade. The foothold of the Christian missionary was yet so precarious in Africa, as to leave it doubtful whether he could sustain his position.