ANTARCTIC ADVENTURE AND RESEARCH 



promontory of Cape Evans and the icy mantle which 

 covered most of Erebus. They consisted of conical 

 piles of kenyte fragments from five feet up to twenty 

 feet high. It was not for some months that we had 

 the opportunity to investigate distant examples, and 

 then their origin was quite clear. About one mile south 

 of Cape Evans, near Lands End, we found all stages 

 of these cones. There was Seal Rock (see a, Figure 

 14), a solid mass of kenyte about ten feet high, but 

 in all probability an erratic block. Higher up the 

 slopes was Thumb Cone {h) with a mantle of debris 

 just beginning to form at the base. Nearby was an- 

 other cone about twelve feet high (r), with only a 

 small portion of the original erratic left at the top. 

 In the vicinitv also were small cones where none of 

 the original erratic was visible {d and e). I cut into 

 a debris cone behind Cape Evans and found a solid 

 core of homogeneous kenyte within. Here "thaw-and- 

 freeze" erosion (nivation) had obviously been pre- 

 vented from acting upon the central portion of the 

 base of the erratic. At Mount Suess we found a com- 

 posite cone which was twenty-five feet high (and about 

 fifty by thirty yards in plan). It w^as surmounted by 

 a block of sandstone lying on edge and about two feet 

 high. But the southwestern end of the same cone was 

 formed of fragments of basalt which were partly cov- 

 ered by sandstone fragments. Evidently here two 

 monoliths of different rock lying side by side had 

 weathered simultaneously. 



Moraines. — All types of these structures occur in 

 Antarctica but they differ in quantity largely from 



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