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Sierra Club Bulletin 



Depth of Yosemite 



Much stress has been laid on the mere uncompared arithmeti- 

 cal depth of Yosemite, but this is a character of no consequence 

 to the consideration of its origin. The greatest Merced Yosemite 

 is 3,000 feet deep; the Tuolumne, 2,000; another, 1,000; but 

 what geologist would be so unphilosophical as to decide against 

 the identity of their origin from difference in depth only. One 

 pine tree is 100 feet high, lean and crooked, from repressing 

 winds and the poverty of the soil which nourished it ; while an- 

 other, more fortunate in the conditions of its life, is 200 feet 

 high, erect and vigorous. So, also, one Yosemite is 3,000 feet 

 deep because of the favorable structure of its rocks and the 

 depth and number of the ice-rivers that excavated it ; another is 

 half as deep, because of the strength of its rocks, or the scanti- 

 ness of the glacial force exerted upon it. What would be thought 

 of a botanist who should announce that our gigantic Sequoia 

 was not a tree at all, offering as a reason that it was too large 

 for a tree, and, in describing it, should confine himself to some 

 particularly knotty portion of the trunk? In Yosemite there is 

 an evergreen oak double the size of ordinary oaks of the region, 

 whose trunk is craggy and angular as the valley itself, and col- 

 ored like the granite bowlders on which it is growing. At a little 

 distance this trunk would scarcely be recognized as part of a 

 tree, until viewed in relation to its branches, leaves and fruit. It 

 is an admirable type of the craggy Merced cafion-tree, whose 

 angular Yosemite does not appear as a natural portion thereof 

 until viewed in its relations to its wide-spreading branches, with 

 their fruit and foliage of meadow and lake. 



We present a ground-plan of three Yosemite valleys, showing 

 the positions of their principal glaciers, and the relation of their 

 trends and areas to them. The large arrows in Figs, i, 2, 3 show 

 the positions and directions of movement of the main confluent 

 glaciers concerned in the erosion of three Yosemites. With re- 

 gard to the number of their main glaciers, the Tuolumne Yo- 

 semite may be called a Yosemite of the third power ; the Kings 

 River Yosemite, of the fourth power ; and the Merced Yosemite, 

 of the fifth power. The granite in which each of these three Yo- 

 semites is excavated is of the same general quality; therefore, 

 the differences of width, depth, and trend observed, are due al- 



