MR. THOMPSON was anxious to lay before the meeting documentary testimony, in preference to any thing he could say himself. Rather than set forth his own views, as he had done on many former occasions, he wished to bring forward such documents as even his opponent would admit to be really American. He pledged himself to show that this was an American question. He was not prepared for this branch of the subject, because he had not expected that Mr. Breckinridge would exonerate America from the charge of being a slaveholding nation; nevertheless, he was perfectly ready to take it up. He would undertake to prove that the existence of slavery in the United States was the result of a compromise--that the Constitution of the United States was, in fact, based upon a compromise, in relation to this subject. At the time when the Constitution was agreed to, the then slaveholding states refused to come into what was called the confederacy of republics, unless slaveholding was permitted. At that time there were only three hundred thousand slaves in the Union; now there were two millions and a half. So much, said Mr. Thompson, for what the good and influential men of the South, spoken of by Mr. Breckinridge, had done for the abolition of slavery. Then there were three hundred thousand; now there were two million four hundred thousand. The method by which these good and influential people had gone about extirpating slavery, had been an Irish method; it had shown distinctly the extent of their zeal and usefulness. Why, setting aside their influence altogether, they might, had they been as numerous as represented by his respected opponent, have manumitted as many of their own slaves. It was said, no doubt, that the laws prevented this; but who made the laws? The child could not do what her mamma had commanded her to do, because she was tied to the mahogany table, she could only answer, when asked who tied her, that it was herself. In like manner, he could turn round on those whom his respected opponent represented, as haters of slavery. Emancipationists they wished to be called; colonizationists they ought to be called. He would ask them, what had they done? Had they not compromised every principle of justice and truth, by permitting slaveholding in their Union? Had they not even bestowed exclusive privileges on the slaveholders? Had they not bestowed on them such privileges as that, even now, they sent twenty-four or twenty-five representatives to Congress more than their proportion? His respected opponent had said this was not a national question. Why, then, send six thousand bayonets to the South for the protection of the slaveholder? Why were the American people taxed in order to maintain bayonets, blunderbusses, and artillery in the South? Not a national question! Why, then, was Missouri admitted a member of the Union--Missouri a slaveholding State, admitted by the votes of the Northern republics. Mr. Breckinridge had fought very shy of the state