76 GLACIOLOGY 



remove the snow drifted to the north of the Nordenskjold Barrier by the southerly 

 bhzzards. 



It is suggested in the sketch sections that at the eastern end of the Tongue, 

 and along its northern margin, the drifted snow resting on thin glacier ice, or old 

 sea ice, may in itself form the bulk of the Tongue there for some distance inwards 

 from the sea cliff. If the width of the Mawson Glacier, as shown on the plan, be 

 compared with that of the Nordenskjold Ice Tongue, the widths agree so closely 

 that it seems unlikely that any considerable addition can have been made to the 

 Tongue there by drift snow. There can be little doubt that along this northern 

 edge, where the height of the ice-cliff is only 50 feet, snow must contribute to 

 form some part of it. 



A question which the plan of this Tongue at once suggests is, in view of the 

 thinness of the neck by which it is attached to the Mawson Glacier, wliy does 

 not the whole mass break off bodily and float away ? Unfortunately time did 

 not admit of our examining its inland end. It is probable that its western end 

 is aground, either on a rock bottom, or more probably on its own bottom moraine, 

 or fluvio-glacial bank. 



There are slight traces of crevasses to be seen only near the southern margin. 

 It appears to represent a senile stage in the history of a glacier afloat, once part 

 of a large piedmont aground. 



The next sketch shows a deep valley, the Cotton Valley, which comes in to join 

 the Mawson Glacier Valley near the base of Mount Murray. 



Hills oF plateau M?Murraj' CoUonVallc> 



onMorthsldeor CaoeDav a deep valley coming in to 



MaMson Olader. y^\Kuay , join the Mawson ClacierValley 



1 : : i 



Piedmont ClaclerlceonSmiUiiMe low rock ctlfT shoHingfyldence ^ • N?M^M6M ^^mont 



or lOewson Glacier. of having been stroogly glaciated. naraensHjom pieaniuin.. 



Fig. 32 



West coast of Ross Sea, looking west, at point on sea ice 13 miles south 

 of the Nordenskjold Ice Tongue 



From this sketch it would appear that the Nordenskjold Ice Tongue is all but 

 detached from the Mawson Glacier. 



In the next sketch (Fig. 33), 5 miles south of the Nordenskjold Barrier, 

 thick masses of piedmont aground are seen between the coast and Mount Chet- 

 wynd (5000 feet). A deep ravine (ice barranca) intersected the piedmont near the 

 coast to the right of Mount Chetwynd. 



At the point where the dark capping is seen on the right of the section there 

 was an appearance suggestive of a cirque. There can be little doubt that here 

 there is a great thickness of basic rock, overlying what appears to be a sedimentary 



