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EXPLANATION OF PLATE V 

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KETTLE-HOLES NEAR HIDDEN GLACIER 



Kettle-holes are ascribed to the melting out of ice masses that had 

 been buried by the rapid accumulation of gravel or sand. In the 

 cases pictured the burying material was gravel washed from Hidden 

 Glacier, and the ice masses were originally part of the glacier. 



The Upper Figure shows a fresh-formed example, the steep walls 

 exhibiting the gravel deposit in section. It shows also the gentle 

 terminal slope of the glacier, the smooth sculpture of its valley wall, 

 and the mouth of a hanging valley. See pages 55 and 118. 



The Lower Figure shows a less advanced stage of the same phe- 

 nomenon. After settling had commenced, the spot received a deposit of 

 mud, and this mud was cracked as the settling proceeded. 



Photographed by G. K. Gilbert, June, 1899. Negatives NOS. 371 

 and 372, United States Geological Survey. 

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