L] GEOLOGICAL OBSERVATIONS 347 



by the Snow Valley until their supply was cut off by decrease of 

 precipitation, and they now lie as relics among the comparatively 

 ice-free hills. 



Icebergs. 



When the slow rate of movement of the glaciers of South 

 Victoria Land is considered, we are driven to the conclusion that 

 they do not supply an appreciable number of icebergs. Therefore 

 the piedmonts afloat, which have been proved to move at the 

 greatest rate, must supply the majority. If this is the case, then 

 the preponderance of the well-known tabular form is not surprising. 

 It has long been established that bergs travel with the ocean- 

 currents, so that little need be said regarding the transport of rock- 

 material by floating ice beyond stating that the drift is north up 

 the coast of South Victoria Land ; therefore any rock-fragment 

 dredged from the sea-bottom in the Ross quadrant must have 

 come from a point further to the south. 



The Moraines. 



The so-called beach at Cape Adare appears to be a collection 

 of old moraines, and even on the summit of the cape at an alti- 

 tude of 800 feet moraines and ice-scratched stones may be seen. 



On Possession Island as well as in Wood Bay similar flat areas 

 covered by moraines are said to occur, and Mr. Morrison's 

 description of the beach on Franklin Island leads one to suppose 

 that here also ice has played its part. These observations are in 

 keeping with those made on Ross Island and elsewhere during our 

 stay in the Antarctic, and the simplest explanation of the occurrence 

 of isolated moraines in this frigid region is that the ice was once 

 developed on a greater scale than at present. Other moraines 

 have been seen near Cape Crozier, above the cliffs on the eastern 

 side of Mount Terror, near Winter Quarters, and on the side of 

 Mount Erebus above Cape Royds. The islands at the south end 

 of McMurdo Sound, and also the ice between them, are literally 

 buried in transported material. 



Englacial rock debris is only encountered near the snouts of 

 glaciers, where it is usually found in well-defined layers separated 

 by almost pure ice. The Blue Glacier and the ice-slabs in the 

 foothills of the Royal Society Range afford the best examples, and 

 tliese are brought into prominence by the fact that thawing usually 



