THE ROSS BARRIER 125 



such as he describes in his own southern journey. Scott's conclusion that the 

 greater part of the Barrier is afloat, is based on the following considerations : — 



1. When his ship, the Discovery, was lying alongside the Barrier in Balloon 

 Bight,* its rail was about level with the Barrier surface there, so that he was in an 

 excellent position to judge of any differential vertical movement between the ship 

 and the Barrier. Although there was evidence of a considerable tide, ship and 

 Barrier rose and fell regularly together. 



2. The soundings, taken by him along the Barrier face, proved that the water 

 was too deep to admit of the material of which the Barrier is formed resting on the 

 bottom. For example: at a point at the base of the Barrier cliff, 115 miles E.S.E. 

 of Cape Crozier, he found a depth of 455 fathoms. The adjacent cliff was only 

 60 feet high. 



3. His survey of the Barrier showed that, in places, masses of ice, as much 

 as 35 to 40 miles in width, had gone out to sea since the edge of the Barrier 

 was charted by Sir James C. Boss in 1841-2. Scott's numerous soundings in 

 300 fathoms were consequently made at spots many miles to the south of where 

 the northern margin of the Barrier was situated in Ross' time. The observations 

 made by the Discovery Expedition also show that, where the Barrier is constricted, 

 as between White Island and Cape Armytage, it is thrown into a series of 

 undulations, implying a continuous thrust from a southerly direction. 



Scott also records {Voyage of Discovery, vol. ii. p. 312) vast disturbances in the 

 surface of the Barrier off the eastern slope of Mount Terror : " Here the sheet is 

 pressing up and shearing past the land ice, raising numerous huge parallel pressure- 

 ridges." A fine illustration of this is published in the above work, large edition, 

 vol. ii. p. 303. 



On his first Southern journey Scott encountered heavy undulations in the surface 

 of the Barrier opposite Shackleton Inlet, and Lieutenant M. Barne, of the same ex- 

 pedition, met similar heavy undulations and disturbances in the Barrier surface 

 opposite Barne Inlet. Speaking of Barne Inlet, Scott states (oj). cit., vol. ii. j). 221) : 

 " It seems evident that the whole of this area is immensely disturbed, and it is 

 doubtful whether a sledge-party could ever cross it, unless they were prepared to 

 spend many weeks in the attempt." Barne's sledge journey also proved the im- 

 portant fact that Scott's Depot A, near Minna Bluff, had moved no less than 608 

 yards in 13 J months. This showed that the whole of the Barrier in this region was 

 obviously in movement. Scott gives the direction in which it is travelling as a 

 little to the east of north. 



4. Scott states {op. cit., p. 312) that Lieutenant C. W. R. Royds took some serial 

 temperatures in a crevasse extending from the north end of White Island near 

 Mount Erebus. " Close to the land, he found that the temperature fell with the 



* This is now merged into the Bay of Wbales, as discovered by our expedition, the spot where 

 Amundsen wintered in 1911, before bis famous journey to the South Pole. 



R 



