76 DISCOVERY REPORTS 



5000 m. (2734 fm.) were obtained here by the ' Discovery II ' and it is probable that these are connected 

 by a small trench. Forty-five miles approximately w^est-by-south of this is another small area where 

 depths of more than 5000 m. were obtained by the 'Meteor' in 1926. The area between these soundings 

 and those taken by us is completely unsounded and it is reasonable to suppose that further observations 

 will show that a long but narrow trench extends over the whole distance. North of our 5000 m. 

 soundings is a small bank, with depths of less than 2000 m. (1094 fm.). In fact, this area is very similar 

 in structure to the area north of the South Orkney Islands, except that the slope from the deep water 

 here appears to be slight but regular and the shelf to the north of the South Shetlands is fairly wide. 



Fig. 15. The Scotia Arc. Positions of soundings and contours of the bottom for the section of the Arc 

 between the South Orkneys and Clarence Island. 



Between King George Island and Elephant Island information is scanty, but such evidence as is 

 available no longer supports our original conception of a connexion here at depths of less than 250 m. 

 (137 fm.); it now appears more likely that the average depth of water on the ridge is less than 500 m. 

 (273 fm.), with a small bank of less than 250 m. in the centre. To the north of Elephant Island one 

 line of soundings, however, showed that the rise from 1872 fm. (3423 m.) to 151 fm. (276 m.) was at 

 an angle of approximately 13°. 



If we now consider the contours of the Bransfield Strait in conjunction with those of the bottom west 

 of Clarence Island it will be found that the deeper water of the strait can be traced, by means of the 

 looom. (547 fm.) contours, to a position to the north of Coronation Island, South Orkneys. Admittedly, 

 the trough south of Clarence Island is very narrow, but there can be little doubt that it exists. The 

 average depth of water on the ridge south of the trough is less than 1000 m. for a large part of its 

 length; it seldom exceeds 2000 m. (1094 fm.) in depth and there is an extensive area south of Clarence 

 Island where the soundings are less than 500 m. (273 fm.). The least depth determined by us on this 



