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Sierra Club Bulletin 



and its depth perhaps nowhere much exceeded 700 feet. Its 

 chief fountains were ranged along the western side of the Mer- 

 ced spur at an elevation of about io,cx)0 feet. These gave birth 

 to magnificent affluents, flowing in a westerly direction for sev- 

 eral miles, in full independence, and uniting near the center of 

 the basin. The principal trunk curved northward, grinding 

 heavily against the lofty wall forming its left bank, and finally 

 poured its ice into Yosemite by the South Cafion between Gla- 

 cier Point and Mount Starr King. All the phenomena relating 

 to glacial action in this basin are remarkably simple and order- 

 ly, on account of the sheltered positions occupied by its princi- 

 pal fountains with reference to the unifying effects of ice-cur- 

 rents from the main summits of the chain. A fine general view, 

 displaying the principal moraines sweeping out into the middle 

 of the basin from Black, Red, Gray, and Clark mountains may 

 be obtained from the eastern base of the cone of Starr King. 

 The right lateral of the tributary which took its rise between 

 Red and Black mountains is a magnificent piece of ice-work. 

 Near the upper end, where it is joined to the shoulder of Red 

 Mountain, it is 250 feet in height, and displays three well- 

 marked terraces. From the first to the second of these, the ver- 

 tical descent is eighty-five feet, and inclination of the surface 

 fifteen degrees; from the second to the third, ninety-five feet, 

 and inclination twenty-five degrees ; and from the third to 

 the bottom of the channel, seventy feet, made at an angle of 

 nineteen degrees. The smoothness of the uppermost terrace 

 shows that it is considerably more ancient than the others, 

 many of the blocks of which it was composed having crumbled 

 to sand. 



A few miles farther down, the moraine has an average slope 

 in front of about twenty-seven degrees, and an elevation above 

 the bottom of the channel of six hundred and sixty-six feet. 

 More than half of the side of the channel from the top is cov- 

 ered with moraine matter, and overgrown with a dense growth 

 of chaparral, composed of manzanita, cherry, and castanopsis. 

 Blocks of rose-colored granite, many of them very large, occur 

 at intervals all the way from the western base of Mount Qark 

 to Starr King, indicating exactly the course pursued by the ice 

 when the north divide of the basin was overflowed. Mount 



