"The Wilmot Proviso has been before the country some time. It has been repeatedly discussed in Congress, and by the public press. I am strongly impressed with the opinion that a great change has been going on in the public mind upon this subject,--in my own as well as others; and that doubts are resolving themselves into convictions, that the principle it involves should be kept out of the national Legislature, and left to the people of the Confederacy in their respective local governments. "Briefly, then, I am opposed to the exercise of any jurisdiction by Congress over this matter; and I am in favor of leaving the people of any territory which may be hereafter acquired, the right to regulate it themselves, under the general principles of the Constitution. Because, "1. I do not see in the Constitution any grant of the requisite power to Congress; and I am not disposed to extend a doubtful precedent beyond its necessity,--the establishment of territorial governments when needed,--leaving to the inhabitants all the rights compatible with the relations they bear to the Confederation." These extracts show, that, in 1846, Gen. Cass was for the Proviso _at once_; that, in March, 1847, he was still for it, _but not just then_; and that in December, 1847, he was _against_ it altogether. This is a true index to the whole man. When the question was raised in 1846, he was in a blustering hurry to take ground for it. He sought to be in advance, and to avoid the uninteresting position of a mere follower; but soon he began to see glimpses of the great Democratic ox-gad waving in his face, and to hear indistinctly a voice saying, "Back!" "Back, sir!" "Back a little!" He shakes his head, and bats his eyes, and blunders back to his position of March, 1847; but still the gad waves, and the voice grows more distinct, and sharper still,--"Back, sir!" "Back, I say!" "Further back!" and back he goes to the position of December, 1847; at which the gad is still, and the voice soothingly says, "So!" "Stand still at that." Have no fears, gentlemen, of your candidate: he exactly suits you, and we congratulate you upon it. However much you may be distressed about our candidate, you have all cause to be contented and happy with your own. If elected, he may not maintain all, or even any, of his positions previously taken; but he will be sure to do whatever the party exigency, for the time being, may require; and that is precisely what you want. He and Van Buren are the same "manner of men;" and, like Van Buren, he will never desert you till you first desert him. [After referring at some length to extra "charges" of Gen. Cass upon the Treasury, Mr. Lincoln continued:---]