Again, he was a lover of nature. The quality which we should call mystery in a painting, and which belongs so particularly to the aspect of the external world and to its influence upon our feelings, was one which he was never weary of attempting to reproduce in his books. The seeming significance of nature's appearances, their unchanging strangeness to the senses, and the thrilling response which they waken in the mind of man, continued to surprise and stimulate his spirits. It appeared to him, I think, that if we could only write near enough to the facts, and yet with no pedestrian calm, but ardently, we might transfer the glamour of reality direct upon our pages; and that, if it were once thus captured and expressed, a new and instructive relation might appear between men's thoughts and the phenomena of nature. This was the eagle that he pursued all his life long, like a schoolboy with a butterfly net. Hear him to a friend: "Let me suggest a theme for you--to state to yourself precisely and completely what that walk over the mountains amounted to for you, returning to this essay again and again until you are satisfied that all that was important in your experience is in it. Don't suppose that you can tell it precisely the first dozen times you try, but at 'em again; especially when, after a sufficient pause, you suspect that you are touching the heart or summit of the matter, reiterate your blows there, and account for the mountain to yourself. Not that the story need be long, but it will take a long while to make it short." Such was the method, not consistent for a man whose meanings were to "drop from him as a stone falls to the ground." Perhaps the most successful work that Thoreau ever accomplished in this direction is to be found in the passages relating to fish in the "Week." These are remarkable for a vivid truth of impression and a happy suitability of language, not frequently surpassed.