Washington Dispatches.
--No action was taken at the caucus of Southern Senators. It was called principally to ascertain the extent of the secession movement in the Cotton States, and to learn, by exchange of opinions, whether the South could be united compactly upon some common basis. No doubt was expressed but that Georgia, Alabama, Mississippi, Florida and South Carolina would secede by ordinances. Senators present from those States represented that no interposition now could arrest that first step, though their ultimate relation to the Union might be effected by future developments. Messrs. Bayard, Pearce, Nicholson, Powell and Crittenden were in favor of making every effort to protect the rights of the South in the Union. Mr. Mason also favored the same view, while requiring guarantees and expressing misgivings as to the result. Mr. Hunter was willing to go farther for conciliation than his recent letter indicated. Mr. Brown advocated immediate secession as the only remedy. But Mr. Davis thought other means should be exhausted before proceeding to that extremity. Mr. Slidell was among the most ultra, and declared that Louisiana could not be restrained from taking position with the seceding States, even if her representatives in Congress were opposed to that policy. Mr. Iverson was not present.Mr. Buchanan is anxiously awaiting the result of a mission he sent to South Carolina on Thursday last, to induce Gov. Gist and the leading Disunionists not to attempt the seizure of the forts in Charleston harbor, until after the fourth of March. William H. Trescott, Assistant Secretary of State--a South Carolinian and secessionist — has been dispatched on this business, and, of course, carries with him an assurance that the President would not interfere to prevent South Carolina from going out.
