ON THE CRATER OF MOUNT SHASTA. 



31 



well-marked naked old moraines at least two miles in length, 

 whicli sweep round to the volcano above referred to, and appar- 

 ently connect with the terminal moraine of a small narrow gla- 

 cier just east of the Whitney Glacier, and which may formerly 

 have been an upper eastern branch of it. This, perhaps, is the 

 Ash Creek Glacier, which lies on the northeast slope of the moun- 

 tain, while the McCloud Glacier lies farther to the eastward. 



The terminal moraines at the end of the Whitney Glacier, 

 which are not, as in Swiss glaciers, clearly demarked from the 

 end of the glaciers themselves, but form an exceedingly irregular 

 and broken field of rocks and debris covering and burying the 

 ice, with many sinks or basins and " kettles," enabled me to 

 clearly understand the mode of formation of the " kettles " or 

 deep holes, at times still filled with water, which are so marked 

 in Massachusetts, near Salem and Marblehead, and also at the 

 " Dumplings " on Canonicut Island near Newport, Rhode Island. 



In his account of the McCloud Glacier of Mount Shasta in his 

 entertaining Mountaineering in the Sierra Nevada, Mr. Clarence 

 King states that for " at least a mile's width the whole lower zone 

 is buried under accumulation of morainal matter. Instead of 

 ending like most Swiss glaciers, this ice wastes chiefly in contact 

 with the ground, and when considerable caverns are formed the 

 overlying moraine crushes its way through the rotten roof, mak- 

 ing the funnels we had seen." 



These immense fields of morainal matter overlying and bury- 

 ing the melting edge of the glacier, here spreading out over the 

 lower flanks of the mountain, were evident signs of the waning 

 of the ice, the glacier having long since ceased to advance ; and 

 it enabled me, as never before, to understand that the peculiar 

 hills and basins or kettles of the great terminal moraine of south- 

 ern New England were formed by the irregular melting of the 

 southern edge of the glacier, when through and under the mass 

 of ice, perhaps not over from three to five hundred feet thick, 

 ran subglacial streams and rivers, while here and there, owing to 

 the uneven melting of the ice, immense masses of gravel and 

 bowlders had fallen in, the material adjoining being rearranged 

 into rounded kames, so characteristic of our New England 

 scenery. 



The rocks on the eastern side of the middle portion of the 

 Whitney Glacier were rounded and polished, as much as such 

 hard rock could well be, when the glacier was of greater volume 

 than now. At present the ice has melted away from the sides of 

 the rock overlooking it. So far as I could see from my point of 

 view, the surface was not grooved or striated. 



That the glacier was in motion was proved by the not infre- 

 quent distant explosions caused by the rupture of the ice near the 



