These sixteen or seventeen volumes are John Burroughs's most characteristic and important work. If he has done any desirable thing, made any real contribution to American literature, that contribution will be found among these books. His other books are eminently worth while: there is reverent, honest thinking in his religious essays, a creedless but an absolute and joyous faith; there is simple and exquisite feeling in his poems; close analysis and an unmitigatedness wholly Whitmanesque in his interpretation of Whitman; and no saner, happier criticism anywhere than in his "Literary Values." There are many other excellent critics, however, many poets and religious writers, many other excellent nature-writers, too; but is there any other who has written so much upon the ways of nature as they parallel and cross the ways of men, upon so great a variety of nature's forms and expressions, and done it with such abiding love, with such truth and charm? Yet such a comparison is beyond proof, except in the least of the literary values--mere quantity; and it may be with literature as with merchandise: the larger the cask the greater the tare. Charm? Is not charm that which I chance to like, or _you_ chance to like? Others have written of nature with as much love and truth as has John Burroughs, and each with his own peculiar charm: Audubon, with the spell of wild places and the thrill of fresh wonder; Traherne, with the ecstasy of the religious mystic; Gilbert White, with the sweetness of the evening and the morning; Thoreau, with the heat of noonday; Jefferies, with just a touch of twilight shadowing all his pages. We want them severally as they are; John Burroughs as he is, neither wandering "lonely as a cloud" in search of poems, nor skulking in the sedges along the banks of the Guaso Nyero looking for lions. We want him at Slabsides, near his celery fields, or at Woodchuck Lodge overlooking the high fields that run down from the sky into Montgomery Valley. And whatever the literary quality of our other nature-writers, no one of them has come any nearer than John Burroughs to that difficult ideal--a union of thought and form, no more to be separated than the heart and the bark of a live tree. Take John Burroughs's work as a whole, and it is beyond dispute the most complete, the most revealing, of all our outdoor literature. His pages lie open like the surface of a pond, sensitive to every wind, or calm as the sky, holding the clouds and the distant blue, and the dragon-fly, stiff-winged, and pinned to the golden knob of a spatter-dock.