TOPOGRAPHY AND EVIDENCE OF VALLEY GLACIERS 441 



In both the South and North basins, and also below their entrance, are 

 a number of lakes, whose location is shown on the accompanying model 

 (see plate 31). As one looks down from any part of the wall of either 

 the South or North basin, his eye rests on an irregular floor, which has 

 every appearance of being a moraine (see plates 32 and 39), and which 

 is dotted with numerous small lakes, ponds, and swamps. 



Evidence of Valley Glaciers 



In preface to this section it is well to call attention to the present 

 climatic conditions of Ktaadn. Throughout the winter the mountain 

 is deeply snow-covered, and the winds whirl vast quantities of snow into 

 the basins. So deep is the snowdrift that in both the North and South 

 basins large snow banks still remained on June 27 (see plate 33), and 

 seemed liable to remain for a week or two longer. In September the 

 snow commences to fall again, and in fact sno'vv squalls occur through- 

 out the summer. It snowed while our party was on the mountain, on 

 June 26. A very slight change in the climate, through increased eleva- 

 tion or decrease in the mean annual temperature, would bring about 

 conditions of glaciation on Ktaadn at present. 



That valley glaciers have descended from the tableland and from the 

 various peaks into the South and North basins no one will question who 

 has seen the evidence, which is very clear and of different kinds. In the 

 first place, the remarkable smoothness of the precipitous rock walls (see 

 plates 34 and 35) is evidence that they have been only recently exposed to 

 the weather. The difference in appearance between these slopes and the 

 same rocks upon the mountain top is very noticeable. They are so pre- 

 cipitous that extensive avalanches (see plate 34) frequently occur, several 

 having fallen within the last few years. Moreover, the walls are exposed 

 to vigorous frost action, to heavy water action, and to fierce winds; yet 

 the amount of weathering since they were exposed to the air has been 

 exceedingly slight. While no glacial scratches were detected and no 

 polishing that was evidently due to ice action, the very smoothness of 

 the walls and the minute development of talus at the base of the cliffs 

 are striking evidences that the walls have not long been open to the air. 



The resemblance between the steep, smooth w T alls of these basins and 

 the sides of certain valleys in the Nugsuak peninsula of Greenland, from 

 which the glaciers are just now leaving, attracted my attention at once. 

 In that portion of Greenland there are places from which the glaciers 

 have almost entirely withdrawn, leaving in their place either entirely 

 stagnant snow patches, which protect the rock from the frost, or else 

 almost stagnant hanging glaciers, which scarcely deserve the name gla- 



LXIII— Bult,. Geol. Soc. Am., Vol. 11, 1899 



