The debates in both houses of Congress last week, on the slave question were highly interesting and important. The resolution introduced in the Senate by Mr. Mason, for an inquiry into the Harper's Ferry affair, gave rise to the discussion in that body. The resolution is admitted on all hands to be a proper one, yet the Republican Senators have, in an apparently factious spirit, delayed its passage. These same gentleman, however, have unanimously and with every appearance of sincerity, denounced Brown's enterprise, and disclaimed for themselves and the great mass of their people any sympathy for such interferences with our rights.

Helper's book is the subject under discussion in the House of Representatives. Many of the Republican members, including Sherman, their candidate for Speaker, recommended the book for general circulation in the Presidential canvass of 1856. They cannot relieve themselves of the odium which justly attaches to their act, but it is gratifying to see that they repudiate the sentiments of the book and seem ashamed of the business. Sherman and others declare that they hold no opinions hostile to the rights of slaveholders, and that they never read or saw Helper's publication, although they endorsed it! As remarked by a member, Mr. Sherman is not the right sort of man for Speaker, as he might sign bills without knowing what they contain. It is proper, however, that he should have the benefit of his own explanation. We state therefore that Francis P. Blair says Helper promised to expunge "the obnoxious matter" from the work, and it was upon this assurance that many members of Congress were induced to recommend it. The New York Tribune also says, the extracts from Helper's book, published in the papers, "were not in the compendium prepared for general circulation, and the Congressional names appended to them are, therefore, morally forged, as they never recommended any such sentiments."

Some of the Democratic members improved the opportunity to make a little party capital.- -Senator Mallory, of Florida, thought "the only safety for the country would be found in the Democratic party." Mr. Reuben Davis, of Mississippi, proclaimed in the House that "it was the duty of all conservative and patriotic men to rally to the support of the Democracy, the only national party." Senator Iverson, of Georgia, another Democrat, was not quite so complimentary. "He believed the Northern portion of the Democracy was as rotten on this question as the Black Republicans." If Sherman was elected Speaker of the House, he would counsel his constituents to break up the Union. "That would be his advice, but he did not know that his people would follow it, for he was considered even in Georgia a little ultra." Rather so.

The intemperate zeal of a certain class of Southern members was illustrated at one stage of the debate. Mr. Nelson, of Tenn., delivered an eloquent and patriotic speech in favor of a peaceable settlement of the pending difficulties, when what does Mr. R. A. Pryor do but pounce upon him as fiercely as if he had advocated abolition sentiments. We regret that the management of affairs for Virginia and the South is not left to such men as Mr. Millson, of Norfolk, whose calm and statesmanlike speech was in striking contrast to the harangues of some of his colleagues.