ANTARCTIC ADVENTURE AND RESEARCH 



main Ferrar Glacier there were three or four low 

 ridges due to the lateral pressure, which were about 

 six feet only above the general level and very broad. 

 These pressure ridges in the Ferrar Glacier were di- 

 rectly opposite the Herbertson Glacier, and not some- 

 what downstream as one would expect if the Ferrar 

 were moving. Evidently the Ferrar Glacier is nearly 

 stagnant along this wall, as indeed the ice tongue fixed 

 to Bowers Piedmont a little lower down also indicates. 

 I have elsewhere drawn attention to the similarity 

 in structure between these "ice-steps" and ridges due 

 to lateral pressure against the Ferrar and the fault 

 blocks and graben of southeast Australia. It may be 

 that pressure from the direction of New Zealand 

 against the resistant shield of Western Australia has 

 broken the Victorian Highlands into a similar series 

 of fault blocks or horsts, as the topography indicates. 



Glacier Tongues 



Four of these peculiar structures were examined 

 by the writer in some detail. Six miles south of Cape 

 Evans is the well-known tongue which is probably the 

 sole example on Ross Island and may therefore be 

 called the Ross Island Tongue (see J, Figure 19). 

 Across MacMurdo Sound is the tongue forming the 

 southeast extremity of the Ferrar Glacier. It differs 

 considerably from the other three in that it is stagnant 

 and asymmetric. In Granite Harbor on the southern 

 coast is the small Harbor Tongue which is connected 

 with the Wilson Piedmont. Finally the most impres- 

 sive of the four is the Mackay Tongue which occupies 



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