This brushy, berry-bearing region used to be a deer and bear pasture, but since the disturbances of the gold period these fine animals have almost wholly disappeared.  Here, also, once roamed the mastodon and elephant, whose bones are found entombed in the river gravels and beneath thick folds of lava.  Toward noon, as we were riding slowly over bank and brae, basking in the unfeverish sun-heat, we witnessed the upheaval of a new mountain-range, a Sierra of clouds abounding in landscapes as truly sublime and beautiful—­if only we have a mind to think so and eyes to see—­as the more ancient rocky Sierra beneath it, with its forests and waterfalls; reminding us that, as there is a lower world of caves, so, also, there is an upper world of clouds.  Huge, bossy cumuli developed with astonishing rapidity from mere buds, swelling with visible motion into colossal mountains, and piling higher, higher, in long massive ranges, peak beyond peak, dome over dome, with many a picturesque valley and shadowy cave between; while the dark firs and pines of the upper benches of the Sierra were projected against their pearl bosses with exquisite clearness of outline.  These cloud mountains vanished in the azure as quickly as they were developed, leaving no detritus; but they were not a whit less real or interesting on this account.  The more enduring hills over which we rode were vanishing as surely as they, only not so fast, a difference which is great or small according to the standpoint from which it is contemplated.

At the bottom of every dell we found little homesteads embosomed in wild brush and vines wherever the recession of the hills left patches of arable ground.  These secluded flats are settled mostly by Italians and Germans, who plant a few vegetables and grape-vines at odd times, while their main business is mining and prospecting.  In spite of all the natural beauty of these dell cabins, they can hardly be called homes.  They are only a better kind of camp, gladly abandoned whenever the hoped-for gold harvest has been gathered.  There is an air of profound unrest and melancholy about the best of them.  Their beauty is thrust upon them by exuberant Nature, apart from which they are only a few logs and boards rudely jointed and without either ceiling or floor, a rough fireplace with corresponding cooking utensils, a shelf-bed, and stool.  The ground about them is strewn with battered prospecting-pans, picks, sluice-boxes, and quartz specimens from many a ledge, indicating the trend of their owners’ hard lives.

The ride from Murphy’s to the cave is scarcely two hours long, but we lingered among quartz-ledges and banks of dead river gravel until long after noon.  At length emerging from a narrow-throated gorge, a small house came in sight set in a thicket of fig-trees at the base of a limestone hill.  “That,” said my guide, pointing to the house, “is Cave City, and the cave is in that gray hill.”  Arriving at the one house of this one-house city,