Studies in the Sierra 



79 



thus hurled into existence at a single effort, they are the most 

 changeless and indestructible soil formations in the Sierra. 

 Excepting those which were launched directly into the chan- 

 nels of rivers, scarcely one of their wedged and locked boulders 

 has been moved since the day of their creation. In striking 

 contrast with these terrible demonstrations of mechanical ener- 

 gy, made in the deposition of earthquake soils, is the silent and 

 motionless transformation of solid granite into loose fine soil- 

 beds by oozing water and the tranquil play of the atmosphere. 

 Beds eight or ten feet deep occur on Mounts Watkins and El 

 Capitan, on the edge of the Yosemite Valley, where the decom- 

 position had been effected so calmly that the physical structure 

 presents no conspicuous change; the quartz, mica, and horn- 

 blende retaining the same relative positions as when solid, yet 

 so perfectly disintegrated that, like sand, it may be cut into 

 with a spade. But these unmoved beds created on the spot are 

 of relatively small extent, and as yet play an insignificant part 

 in the support of Sierra vegetation. The main body of the 

 smaller soil-fragments, weathered loose by the atmosphere, are 

 transported and redeposited by winds and rains. Magnificent 

 wind-rivers sweep the high Sierra, carrying large quantities of 

 sand, dust, and mica flakes, besides larger fragments in the 

 form of rough grains. These are distributed in smooth undu- 

 lating fields and patches, adapted to the wants of the dwarf 

 Pinus alhicaulis and many of the most precious of Sierra 

 shrubs and flowers. Many of the smaller alpine wind-beds are 

 exceedingly beautiful, nestling in the lee of rough beaten rocks, 

 their edges waved and embroidered, and their surfaces delicate- 

 ly dinted and ruffled like the garden-plats of children. During 

 the post-glacial eruptions of the volcanoes of the Mono basin, 

 winds distributed showers of cinders and ashes upon all the 

 soil-beds of the adjacent Sierra. Hundreds of square miles of 

 area are thus sprinkled on the upper basins of the San Joaquin, 

 Merced, and Tuolumne rivers; the copiousness of the cinder- 

 showers increasing the nearer the Mono volcanoes are ap- 

 proached as a center. 



The numerous domes and castellated rocks distributed over 

 the ridges and divides of the middle region abound in garnet, 

 tourmaline, quartz, mica, and feldspar crystals, which, as the 



