And what is true of any two men is equally true of any one man at two different times. To-day he is in a dreamy, reflective mood,--he has been reading Wordsworth, perhaps,--and when he takes his afternoon saunter he looks at the bushy hillside, or at the wayside cottage, or down into the loitering brook, and he sees in them all such pictures as they never showed him before. Or he is in a matter-of-fact mood, a kind of stock-market frame of mind; and he looks at everything through economical spectacles,--as if he had been set to appraise the acres of meadow or woodland through which he passes. At another time he may have been reading some book or magazine article written by Mr. John Burroughs; and although he knows nothing of birds, and can scarcely tell a crow from a robin (perhaps for this very reason), he is certain to have tantalizing glimpses of some very strange and wonderful feathered specimens. They must be rarities, at least, if not absolute novelties; and likely enough, on getting home, he sits down and writes to Mr. Burroughs a letter full of gratitude and inquiry,--the gratitude very pleasant to receive, we may presume, and the inquiries quite impossible to answer. Some men (not many, it is to be hoped) are specialists, and nothing else. They are absorbed in farming, or in shoemaking, in chemistry, or in Latin grammar, and have no thought for anything beyond or beside. Others of us, while there may be two or three subjects toward which we feel some special drawing, have nevertheless a general interest in whatever concerns humanity. We are different men on different days. There is a certain part of the year, say from April to July, when I am an ornithologist; for the time being, as often as I go out-of-doors, I have an eye for birds, and, comparatively speaking, for nothing else. Then comes a season during which my walks all take on a botanical complexion. I have had my turn at butterflies, also; for one or two summers I may be said to have seen little else but these winged blossoms of the air. I know, too, what it means to visit the seashore, and scarcely to notice the breaking waves because of the shells scattered along the beach. In short, if I see one thing, I am of necessity blind, or half-blind, to all beside. There are several men in me, and not more than one or two of them are ever at the window at once. Formerly, my enjoyment of nature was altogether reflective, imaginative; in a passive, unproductive sense, poetical. I delighted in the woods and fields, the seashore and the lonely road, not for the birds or flowers to be found there, but for the "serene and blessed mood" into which I was put by such friendship. Later in life, it transpired, as much to my surprise as to anybody's else, that I had a bent toward natural history, as well as toward nature; an inclination to study, as well as to dream over, the beautiful world about me. I must know the birds apart, and the trees, and the flowers.