Page:Popular Science Monthly Volume 88.djvu/558

 What Wind and Rain Can Do

How Nature's Chisels Work Through Milhons of Years

��ON the sloping "shores" of the great salt-incrusted playa at the bottom of Death Valley, California, which is the bed of an ancient lake, there is a large volcanic rock which, it is stated, has appeared to grow out of the ground several feet within the memory of the pioneers. When first observed, this was simply a large irregularly-shaped rock resting on the ground. Since then it appears to have been pushed upward. It is supported on a fragile, wedge- shaped neck not over a couple of feet broad. The apparent instability of the

��region, sweeping everything before theif great volume of water.

On the opposite page is pictured another product of wind and rain, probably one of the most singular collec- tions of rock figures in existence. Acres and acres in extent, from a distance they resemble, as much as anything, a vast family or colony of gigantic prairie dogs sitting on their haunches, and covering the entire slopes of Red Mountain, Arizona. The figure of the man in the left center of the photograph indicates the size of these "prairie dogs."

���Mushroom Rock — one of Death Valley's curiosities

��thin neck with its top-heavy burden is accentuated by a good-sized hole in its middle, so that in traveling the trail which passes directly under the rock, the tenderfoot is apt to feel relieved when the formation has been left behind.

Contrary to supposition, there has been no growth or uplift of this rock. The earth at its base has been washed and blown away by the winds and the cloud-bursts, which, on rare occasions occur even in this intensely desert

��This mountain is a cinder cone of the San Francisco plateau, and the village of rock forms has been caused by the cutting and sculpturing of the soft lava by the wind and rain. The cinder cone of a volcano is the last upheaval, the result of the dying gasp of eruption. So stupendous, however, has been the dynamic energy attending many of the earlier volcanic disturbances of the West that there are cinder cones several thousand feet in height.

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