It is very evident from the Southern papers, that the raid of John Brown has injured the chances of Stephen A. Douglas at the South, very materially. The Alabama papers come out openly, and demand that Congress should interfere to compel the establishment of slavery in the territories, and that the doctrine of popular sovereignty should be abandoned. With this feeling, they will demand that the candidate of the Democratic party, nominated at Charleston, shall come out boldly on the platform of the duty of Congress to ESTABLISH slavery in the territories. – They will thus whittle down the Democratic party in the free states to a very small point. The Charleston Mercury claims that the incursion of John Brown is a reason for secession. Why don’t the Government arraign these southern fanatics for inciting to treason – or is it true, that treason cannot be committed except by a northern man?