All outdoor existence, all outdoor phenomena, are deeply interesting to him. There is scarcely a form of outdoor life, scarcely a piece of landscape, or natural occurrence characteristic of the Eastern States, which has not been dealt with suggestively in his pages: the rabbit under his porch, the paleozoic pebble along his path, the salt breeze borne inland by the Hudson, the whirl of a snow-storm, the work of the honey bees, the procession of the seasons over Slabsides, even the abundant soil out of which he and his grapes grew and which, "incorruptible and undefiled," he calls divine. He devotes an entire chapter to the bluebird, a chapter to the fox, one to the apple, another to the wild strawberry. The individual, the particular thing, is always of particular interest to him. But so is its habitat, the whole of its environment. He sees the gem, not cut and set in a ring, but rough in the mine, where it glitters on the hand of nature, and glitters all the more that it is worn in the dark. Naturally John Burroughs has written much about the birds; yet he is not an ornithologist. His theme has not been this or that, but nature in its totality, as it is held within the circle of his horizon, as it surrounds, supports, and quickens him. That nature does support and quicken the spiritual of him, no less than the physical, is the inspiration of his writing and the final comment it requires. Whether the universe was shaped from chaos with man as its end, is a question of real concern to John Burroughs, but of less concern to him than the problem of shaping himself to the universe, of living as long as he can upon a world so perfectly adapted to life, if only one be physically and spiritually adaptable. To take the earth as one finds it, to plant one's self in it, to plant one's roof-tree in it, to till it, to understand it and the laws which govern it, and the Perfection which created it, and to love it all--this is the heart of John Burroughs's religion, the pith of his philosophy, the conclusion of his books. But if a perfect place for the fit, how hard a place is this world for the lazy, the ignorant, the stubborn, the weak, the physically and spiritually ill! So hard that a torpid liver is almost a mortal handicap, the stars in their courses fighting against the bilious to defeat them, to drive them to take exercise, to a copious drinking of water, to a knowledge of burdock and calomel--to obedience and understanding.