GLACIAL STUDIES IN GREENLAND 



587 



crevasses in such a position. A similar system of fracture lines 

 is observable on the side of the Tuktoo glacier facing the Sen- 

 tinel nunatak. The general nature and course of these may be 

 made out from an inspection of Fig. 60, but the details are bet- 



Fic. 61. — A nearer view of the south side of the eastern lobe of the 1 ulctoo glacier 

 from a photograph by Professor Libbey, showing the verticality of the wall, the 

 absence of a moraine at the base, the crevassing in a moderate degree, having the 

 direction usually taken on the side of a glacier, and, particularly, the non-gaping 

 crevices, running transverse to the crevasses. 



ter seen in Fig. 6i. In the upper part of the glacier it will be 

 observed that there are numerous oblique fracture lines starting 

 within the dark band which represents the vertical wall of the 

 glacier and running obliquely backward and upward, curving 

 toward the axis of the glacier. It will be seen that these cross 

 the layers of the ice, which are shown by light and dark banding 

 on the vertical side and b}- parallel ridgings on the upper sur- 

 face of the glacier. The normal system of crevassing may be 

 seen imperfectly by the gaping fissures on the side of the gla- 

 cier at the left in Fig. 60. They are also indicated by the 



