The author (Henry Adams) appears to be contrasting statesmen who play to popular opinion (demagogues, in other parlance; "stage-type" here) with those of the old-school who held their own moral compass and performed actions for the country instead of merely acting for a crowd.
I gather this from a search for more context and offer it here because without such context the example you give is rather opaque.
You can read further by clicking the above link. The passage speaks of Grant and Garfield, among others, who were presidents of the United States after the Civil War. Grant especially was noted for having one of the most corrupt administrations in American political history (up to that time). But the issue seems to be one of public posturing vs. action without regard to what the press wrote and the public thought.