86 DISCOVERY REPORTS 



'Discovery II' turned east, in approximately the longitude of 01^45' E the sounding was 648 fm. 

 (i 185 m.) and when she stood away from the ice during the hours of darkness the depth was 795 fm. 

 (1450 m.) in 69° 47-8' S, 02° 2i-i' E. Soundings remained variable on the return to the barrier on 

 the following day, although there was a sharp rise in the bottom at one place of 328 fm. (600 m.) in 

 approximately 3-5 miles. This rise occurred between the depths of 815 and 487 fm. (1491 and 891 m.). 



Fig. 16. Track of ship along ice barrier and coast of Antarctica, between the longitudes of 

 0° 10' E and 4° 30' E. Continuous recording of soundings throughout. 



Shortly after the return to the barrier the ship was forced to the north by a field of bergs surrounded 

 by heavy pack-ice, and soundings reached a maximum of loiofm. (1847 m.) in 69° 54-8' 8, 03° 32-1' E. 

 From this position the soundings again shoaled rapidly towards the land and after a steady slope 

 a depth of 60 fm. (no m.) was obtained 3 cables off-shore, in 70° 04-6' S, 03° 49-2' E. Land was 

 again approached a few miles farther east and the least sounding obtained was 1 17 fm. (214 m.). Course 

 was then altered to avoid pack-ice and to stand off the coast during the dark hours, but the weather 

 deteriorated rapidly during the night and it was not possible to resume the survey. 



THE CONTINENTAL SHELF OF ANTARCTICA 



This short survey of 140 miles of the ice barrier revealed the interesting fact that over this distance 

 there was virtually no continental shelf in the sense generally understood. Unfortunately, the pack-ice 

 which surrounds the Antarctic Continent throughout the greater part of the year in most sectors makes 

 the approach difficult, and it is only during late summer or autumn that ships can expect to close the 

 land. It is not possible, without much more information than we now possess, to forecast, even 

 remotely, the incidence of pack-ice, and thus any approach to the continent will remain for some years 

 largely a matter of chance. Aerial reconnaissance, however, would be of considerable assistance in 

 a clear ice year. 



The information which has already been obtained from various approaches to the Antarctic Continent, 

 and from running surveys of some short sections of the coast, leads us to believe that in some places 

 the continental shelf is almost completely absent; one such area has just been described. Similar 

 conditions are to be found in other parts of the Atlantic sector, and over considerable lengths of the 

 coast between the meridians of 5° E and 60° E. There appears to be a wide shelf to seaward of the 

 coasts of the Weddell Sea, and off the South Shetlands and South Graham Land there is a marked 

 shelf, some 60-70 miles in width, which becomes wider as it continues south-west into the Bellings- 

 hausen Sea. No ship has ever reached the land between here and the eastern side of the Ross Sea, 



