BYED ANTARCTIC EXPEDITION GOULD 247 



of the greatest questions in the geologic relationship of major struc- 

 tures anywhere in the world remains still to be answered — the rela- 

 tionship of East to West Antarctica. Investigation of the Edsel 

 P'ord Mountains would probably add important and perhaps defini- 

 tive light on this question. These mountains may be not the fault- 

 block type but a folded Andean structure, for it is in this part of the 

 Antarctic that one would expect a continuation of the fold structures 

 of the Antarctic Archipelago if they reappear anywhere. 



THE ROSS SHELF ICE 



Because of the fact that the journey of the geological party threw 

 much light on it, I have left until the end any discussion of the most 

 distinctive of Antarctic glacial features, the Koss Shelf Ice. 



From the time of its discovery by Sir James Clark Koss in 1840 

 to this day the Ross Shelf Ice, to employ a term that seems preferable 

 to Ross Barrier, has impressed Antarctic explorers as one of the 

 unique works of nature. It ends on the north in a dazzlingly white 

 cliff that stretches for 500 miles in an east-west direction roughly 

 in latitude 78° S. It is thus the boundary of the southern navigable 

 limits of the Ross Sea. This great snow-ice cliff prevented Ross 

 from sailing farther south in his quest for the magnetic pole and 

 hence was referred to by him as a barrier. If the term Ross Barrier 

 is to be used at all it should refer only to the northward-facing cliff 

 of this great sheet of shelf ice that covers well over a quarter of a 

 million square miles. 



This cliff, or barrier, varies greatly in height from place to place 

 and from time to time. It was restudied, for the first time after its 

 discovery, by Scott in 1901-1904. He made soundings all along its 

 front and also measured its height above sea level. The sound- 

 ings demonstrated that the water was everywhere too deep for any 

 part of the front of the shelf ice to be resting on the bottom. He 

 found the altitude to vary from 20 to 240 feet above sea level. The 

 next observations were those made by the British Antarctic expedi- 

 tion in 190T-1909 and indicated a height ranging from 20 to 200 feet. 

 When the Terra Nova visited the region in 1911 no spot higher than 

 150 feet was observed. AVe of the Byrd expedition made our first 

 landing at Discovery Inlet. Here we found the height to be 60 feet. 

 From here we sailed eastward along the shelf-ice scarp to the Bay of 

 Whales ; and, though we did not land again to make accurate meas- 

 urements, there was no place along this stretch that seemed higher 

 than at Discovery Inlet. In places it descended as low as from 6 to 

 10 feet. Immediately east of the Bay of Whales, in fact bounding 

 a part of it, the height was found by measurement to be 200 feet. 



