Mark Twain, in short, knew very well--for I think these illustrations prove it--that there was something decidedly different between himself and a great writer. In that undifferentiated mob of celebrities, great, and less great, and far from great, amid which he moved for a generation, he was a favored equal. But in the intimate presence of some isolated greatness he reverted to the primitive reverence of the candidate for the mystagogue. Was it Emerson? He ceased to be a fellow writer, he became one of the devout Yankee multitude. Was it Browning? He forgot the man he had so cordially known in the poet whom he studied for a time with the naïve self-abasement of a neophyte. Was it Mommsen? Read this humorous entry in one of his Berlin note-books: "Been taken for Mommsen twice. We have the same hair, but on examination it was found the brains were different." In fact, whenever he uses the word "literature" in connection with his own work it is with a sudden self-consciousness that lets one into the secret of his inner humility. "I am the only literary animal of my particular subspecies who has ever been given a degree by any college in any age of the world, so far as I know," he writes to the authorities of Yale in 1888. A man who freely compared himself with the melodeon, as distinguished from the opera, who, in the preface to "Those Extraordinary Twins," invited his readers, who already knew how "the born and trained novelist works," to see how the "jack-leg" does it, could never have been accused of not knowing his true rank. "You and I are but sewing-machines," he says in "What Is Man?" "We must turn out what we can; we must do our endeavor and care nothing at all when the unthinking reproach us for not turning out Gobelins."