In the conduct of that remarkable campaign of 1858, Mr. Douglas was the advocate of expediency, Mr. Lincoln of principle. Mr. Douglas appealed to the prejudices of the white race against the black, and argued in favor of present ease and selfish indifference to justice in our conduct as a nation. Mr. Lincoln incessantly appealed to the consciences of his audience, to all that part of human nature which is kindly, which is just, which is noble; to the broad doctrines upon which our national freedom was originally based. It is true that along with these main currents of debate numerous minor questions and side issues came up; but such was the pervading color, the chief drift of the discussion. Over and over and over again, there sounds out among the words of Douglas, "This is a white man's government; the negro ought not to vote." And even more constant is the lofty reply, "I stand by the Declaration of Independence, and the everlasting rights of humanity. The negro is a man, and he ought to have all the rights of a man!" Mr. Lincoln's speech at Springfield, on June 17th, has been briefly described. Mr. Douglas, coming home to his own State, to justify his course, and receive his re-election, answered him in his Chicago speech of July 9th, and Mr. Lincoln rejoined next day. Douglas spoke again, at Bloomington on the 16th, and at Springfield on the 17th, and on the latter day Mr. Lincoln spoke also at Springfield. In this speech he set forth a curious and characteristic contrast between himself and his opponent, in a grotesque and sarcastic manner that must have told sharply upon his western audience, while its comic surface is underlaid with the usual solid basis of conscious adherence to justice and principle. Mr. Lincoln said: