In answer to my proposition at Galesburgh last week, I see that some man in Chicago has got up a letter, addressed to the Chicago Times, to show, as he professes, that somebody had said so before; and he signs himself "An Old-Line Whig," if I remember correctly. In the first place, I would say he was not an old-line Whig. I am somewhat acquainted with old-line Whigs from the origin to the end of that party; I became pretty well acquainted with them, and I know they always had some sense, whatever else you could ascribe to them. I know there never was one who had not more sense than to try to show by the evidence he produces that some men had, prior to the time I named, said that negroes were not included in the term "all men" in the Declaration of Independence. What is the evidence he produces? I will bring forward his evidence, and let you see what he offers by way of showing that somebody more than three years ago had said negroes were not included in the Declaration. He brings forward part of a speech from Henry Clay,--the part of the speech of Henry Clay which I used to bring forward to prove precisely the contrary. I guess we are surrounded to some extent to-day by the old friends of Mr. Clay, and they will be glad to hear anything from that authority. While he was in Indiana a man presented a petition to liberate his negroes, and he (Mr. Clay) made a speech in answer to it, which I suppose he carefully wrote out himself and caused to be published. I have before me an extract from that speech which constitutes the evidence this pretended "Old-Line Whig" at Chicago brought forward to show that Mr. Clay did n't suppose the negro was included in the Declaration of Independence. Hear what Mr. Clay said: "And what is the foundation of this appeal to me in Indiana to liberate the slaves under my care in Kentucky? It is a general declaration in the act announcing to the world the independence of the thirteen American colonies, that all men are created equal. Now, as an abstract principle, there is no doubt of the truth of that declaration; and it is desirable, in the original construction of society and in organized societies, to keep it in view as a great fundamental principle. But, then, I apprehend that in no society that ever did exist, or ever shall be formed, was or can the equality asserted among the members of the human race be practically enforced and carried out. There are portions, large portions, women, minors, insane, culprits, transient sojourners, that will always probably remain subject to the government of another portion of the community.