Faithfully yours, CHARLES SUMNER. WM. M. WERMERSKIRCH, Esq., _Corresponding Secretary of the German Republican Central Committee, New York._ STATE SUICIDE AND EMANCIPATION. LETTER TO A PUBLIC MEETING AT THE COOPER INSTITUTE, NEW YORK, MARCH 6, 1862. This meeting was in pursuance of the following call. “All citizens of New York who rejoice in the downfall of treason, and are in favor of sustaining the National Government in the most energetic exercise of all the rights and powers of war, in the prosecution of its purpose to destroy the cause of such treason, and to recover the territories heretofore occupied by certain States recently overturned and wholly subverted as members of the Federal Union by a hostile and traitorous power calling itself ‘The Confederate States,’ and _all who concur in the conviction that said traitorous power, instead of achieving the destruction of the Nation, has thereby only destroyed Slavery_, and that it is now the sacred duty of the National Government, as the only means of securing permanent peace, national unity and well-being, to provide against its restoration, and _to establish in said territories Democratic Institutions founded upon the principles of the Great Declaration_, ‘That all MEN are created equal, endowed by their Creator with the unalienable rights of Life, Liberty, and the pursuit of Happiness,’ are requested to meet at the Cooper Institute, on the sixth day of March, at eight o’clock, P. M., to express to the President and Congress their views as to the measures proper to be adopted in the existing emergency.” On the day of this great meeting the President communicated to Congress his Message on Compensated Emancipation, which was his first public step in the transcendent cause. The President of the meeting was Hon. James A. Hamilton, the venerable son of Alexander Hamilton, who agreed with Mr. Sumner in regard to the death of Slavery and the power of Congress. There was also a distinguished list of Vice-Presidents, with George Bancroft at the head. There were letters from Preston King, Senator of New York, Henry Wilson, Senator of Massachusetts, David Wilmot, Senator of Pennsylvania, George W. Julian, Representative in Congress from Indiana, and from Mr. Sumner. Among the orators were the President of the meeting, Mr. Martin F. Conway, Representative in Congress from Kansas, and Carl Schurz, who had recently returned from his Spanish mission. The report in the _New York Tribune_ has the caption, “The Suicide of Slavery.--New York for a Free Republic.” Mr. Sumner’s letter was a vindication of his Resolutions. SENATE CHAMBER, March 5, 1862.