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Sierra Club Bulletin 



began to set things right : many long-cherished notions its lines 

 began to substantiate and many long-taught theories they 

 proceeded to disrupt. New revelations presented themselves 

 from day to day. Here were moraines plastered upon the 

 landscape in a manner suggesting that the ice had little or 

 no eroding power, while yonder loomed sharply truncated 

 spurs of solid rock, proclaiming ice erosion of the intensest 

 sort. Here was a moraine ascending hundreds of feet in down- 

 stream direction, while in another place the ice had passed 

 by a gap considerably lower than its surface without taking 

 advantage of the outlet. One glacier after straddling a ridge 

 for miles had split just before reaching a saddle. Why did 

 it balk at the inviting hollow? Surely these glaciers behaved 

 in unexpected ways. 



The interest continued until the very end. The search had 

 been organized in the upper country where ice signs are rela- 

 tively plentiful, and was carried thence to progressively 

 lower levels. Where did the glaciers end? What was the 

 lowest point on the Sierra flank reached by them? Is Muir 

 right in his assertion that the ice enveloped the entire range 

 down to its foot? Such were the questions that urged them>- 

 selves upon the investigator. 



It is scarcely desired here to go into particulars, — it would 

 not be meet thus to anticipate the government's publication, 

 but this much may be stated with propriety: the ice of the 

 earlier epochs was very extensive and descended far beyond 

 the Yosemite, yet it failed to reach the Sierra foot by many 

 miles. The increase of temperature from the 5,000-foot level 

 down to the foothills must have been almost as pronounced in 

 glacial times as it is now. The vast ice fields of the upper 

 Sierra contracted downward into individual ice tongues, and 

 these again, as they protruded below the zone of glacial cli- 

 mate, diminished in strength with great rapidity, in spite of 

 the protection from the sun afforded them by their profound, 

 rock-walled channels. As a consequence the Sierra glaciers 

 came rather abruptly to an end. The evidence of their ter- 

 mination, it should be said, is unmistakable, if faint and hid- 

 den; one must be willing to grope through the manzanita 

 to secure it. 



