Negro Slavery.–Nothing in the United States has surprised me so much as the general tone of the public mind and the press on the subject of slavery. The institutions of America profess to be based on justice, and certainly an all-pervading justice is indispensable to their permanence and success; yet the most cruel injustice is perpetrated on the Negro race, and defended, as if it were justice, by persons whose character and intelligence render them in every other respect amiable and estimable. This is a canker in the moral constitution of the country, that must produce evil continually until it is removed. Those who defend slavery deny the right of foreigners to interfere with it; they speak of it as a domestic institution, with which nobody has any concern except the legislatures of the States in which it exists, and on this ground the House of Representatives of the United States, at Washington, on the 11th December current, refused to receive any petitions on the subject. Mr Atherton, member for New Hampshire, presented a series of five resolutions; the vote was taken on the first resolution, “Resolved, That this Government is of limited powers, and that, by the constitution of the United States, Congress has no jurisdiction whatever over the institution of slavery in the several States of the confederacy;” which was carried, “ayes, 198; noes, 6.”