The historian must, indeed, himself be an investigator. He must know good ore from bad; must distinguish fineness, quality, genuineness; must stop to get out of the records for himself what he lacks for the perfection of his work. But for all that, he must know and stand ready to do every part of his task like a master workman, recognizing and testing every bit of stuff he uses. Standing sure, a man of science as well as an artist, he must take and use all of his equipment for the sake of his art,--not to display his materials, but to subordinate and transform them in his effort to make, by every touch and cunning of hand and tool, the perfect image of what he sees, the very truth of his seer’s vision of the world. The true historian works always for the whole impression, the truth with unmarred proportions, unexaggerated parts, undistorted visage. He has no favorite parts of the story which he boasts are bits of his own, but loves only the whole of it, the full and unspoiled image of the day of which he writes, the crowded and yet consistent details which carry, without obtrusion of themselves, the large features of the time. Any exaggeration of the parts makes all the picture false, and the work is to do over. “Test every bit of material,” runs the artist’s rule, “and then forget the material;” forget its origin and the dross from which it has been freed, and think only and always of the great thing you would make of it, the pattern and form in which you would lose and merge it. That is its only high use.