In the fall of 1873 I was tracing the South Fork of the San Joaquin up its wild canon to its farthest glacier fountains.  It was the season of alpine Indian summer.  The sun beamed lovingly; the squirrels were nutting in the pine-trees, butterflies hovered about the last of the goldenrods, the willow and maple thickets were yellow, the meadows brown, and the whole sunny, mellow landscape glowed like a countenance in the deepest and sweetest repose.  On my way over the glacier-polished rocks along the river, I came to an expanded portion of the canon, about two miles long and half a mile wide, which formed a level park inclosed with picturesque granite walls like those of Yosemite Valley.  Down through the middle of it poured the beautiful river shining and spangling in the golden light, yellow groves on its banks, and strips of brown meadow; while the whole park was astir with wild life, some of which even the noisiest and least observing of travelers must have seen had they been with me.  Deer, with their supple, well-grown fawns, bounded from thicket to thicket as I advanced; grouse kept rising from the brown grass with a great whirring of wings, and, alighting on the lower branches of the pines and poplars, allowed a near approach, as if curious to see me.  Farther on, a broad-shouldered wildcat showed himself, coming out of a grove, and crossing the river on a flood-jamb of logs, halting for a moment to look back.  The bird-like tamias frisked about my feet everywhere among the pine-needles and seedy grass-tufts; cranes waded the shallows of the river-bends, the kingfisher rattled from perch to perch, and the blessed ouzel sang amid the spray of every cascade.  Where may lonely wanderer find a more interesting family of mountain-dwellers, earth-born companions and fellow-mortals?  It was afternoon when I joined them, and the glorious landscape began to fade in the gloaming before I awoke from their enchantment.  Then I sought a camp-ground on the river-bank, made a cupful of tea, and lay down to sleep on a smooth place among the yellow leaves of an aspen grove.  Next day I discovered yet grander landscapes and grander life.  Following the river over huge, swelling rock-bosses through a majestic canon, and past innumerable cascades, the scenery in general became gradually wilder and more alpine.  The Sugar Pine and Silver Firs gave place to the hardier Cedar and Hemlock Spruce.  The canon walls became more rugged and bare, and gentians and arctic daisies became more abundant in the gardens and strips of meadow along the streams.  Toward the middle of the afternoon I came to another valley, strikingly wild and original in all its features, and perhaps never before touched by human foot.  As regards area of level bottom-land, it is one of the very smallest of the Yosemite type, but its walls are sublime, rising to a height of from 2000 to 4000 feet above the river.  At the head of the valley the main canon forks, as is found to be the case in all yosemites.  The formation of this one is due chiefly to the action of two great glaciers, whose fountains lay to the eastward, on the flanks of Mounts Humphrey and Emerson and a cluster of nameless peaks farther south.