THE SPELL OF THE YOSEMITE 
thousand feet high, hung here and there with snow- 
white waterfalls, and supporting the blue sky on 
domes and pinnacles still higher. Oh, the calmness 
and majesty of the scene! the evidence of such tre- 
mendous activity of some force, some agent, and 
now so tranquil, so sheltering, so beneficent! 
That there should be two or three Yosemites in 
the Sierra not very far apart, all with the main fea- 
tures singularly alike, is very significant — as if this . 
kind of valley was latent in the granite of that region 
—some peculiarity of rock structure that lends 
itself readily to these formations. The Sierra lies 
beyond the southern limit of the great continental 
ice-sheet of late Tertiary times, but it nursed and 
reared many local glaciers, and to the eroding power 
of these its Yosemites are partly due. But water was 
at work here long before the ice — eating down into 
the granite and laying open the mountain for the 
ice to begin its work. Ice may come, and ice may 
go, says the river, but I go on forever. Water tends 
to make a V-shaped valley, ice a U-shaped one, 
though in the Hawaiian Islands, where water erosion 
alone has taken place, the prevailing form of the 
valleys is that of the U-shaped. Yosemite approxi- 
mates to this shape, and ice has certainly played a 
part in its formation. But the glacier seems to have 
stopped at the outlet of the great valley; it did not 
travel beyond the gigantic hall it had helped to ex- 
cavate. The valley of the Merced from the mouth 
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