"That, sir, was the leading feature of the compromise measures of 1850. Those measures, therefore, abandoned the idea of a geographical line as a boundary between free States and slave States--abandoned it because compelled to do it from an inability to maintain it--and in lieu of that substituted a great principle of self-government, which would allow the people to do as they thought proper. Now the question is, when that new compromise, resting upon that great fundamental principle of freedom, was established, was it not an abandonment of the old one--the geographical line? Was it not a supersedure of the old one, within the very language of the substitute for the bill which is now under consideration? I say it did supersede it, because it applied its provisions as well to the north as to the south of 36° 30'. It established a principle which was equally applicable to the country north as well as south of the parallel of 36° 30'--a principle of universal application." Mr. Douglas's bill passed both branches of Congress and became a law, after passing through a severe ordeal both in Congress and before the people. Its passage gave the popular branch of the next Congress into the control of Mr. Douglas's political enemies, for the bill in a majority of the free States was very unpopular. On the first Monday in December, 1857, Mr. Douglas took his seat in the Senate with many anxious eyes upon him, for it had already been rumored that he would differ with the administration upon its conduct of Kansas affairs, and would take issue with the President in his forthcoming message. Rumor was right--the message was read--it did in effect recommend the indorsement of the Lecompton Constitution--and Mr. Douglas had the courage and boldness to stand up in defence of his peculiar doctrines of popular sovereignty, which he thought had been violated by the Lecompton Constitution. His great opening speech was delivered on the ninth of December, 1857. The President's message had been read the day previous and Mr. Douglas had indicated his purpose on the next day to speak upon it. Accordingly when the Senate assembled on Tuesday, the old Senate-hall was crowded to its utmost capacity and hundreds were unable to effect an entrance. The curiosity of the public to learn the position which the Illinois senator would take upon this important question was intense, and many of the members of the house were present. Mr. D. rose, apparently as cool as he ever was in his life, although, in the opinion of some of his Democratic friends, his decision, which after careful thought he had reached, to oppose the Lecompton Constitution, would ruin all his political prospects. He began by quoting the peculiar language of the President's message, and, perhaps in a vein of irony, contended that the President was opposed to this Lecompton Constitution, which,