DISCOVERY REPORTS 

 this area, there is' still a gap in the ridge between 30° and 31° 20' W. However, there is still room in 

 this gap for further soundings to reveal better evidence of a connecting ridge. Apart from this the 

 following facts may be cited in general support of the connexion between South Georgia and the 

 South Sandwich Islands. 



(a) The profiles drawn in Text-figs. 12& and c show the typical irregularity of the bottom immedi- 

 ately south of the least depths (i.e. on the inner side of the loop), which is so marked in the Burdwood 

 Bank-South Georgia sector of the Arc. 



{h) The area of less than 3000 m. (1641 fm.) centred about 32° W, with its revised and more 

 elongated outline (from west to east), may represent a crest on the ridge. 



{c) A number of new soundings show that the northern end of the South Sandwich Trench extends 

 westwards as far as 33° 37' 48" W (see PI. XXIII). Since elsewhere the Trench is parallel to and 

 outside the Arc, it may be supposed that part of the ridge lies just south of this westward extension 

 of the 5000 m. (2734 fm.) contour. 



Our original bathymetric chart showed the extension of the ridge on which the South Sandwich 

 Group is situated as running roughly north from Zavodovski Island and then to the west. In late 

 November 1932, soundings on a course approximately north-west from this island located a shallow 

 bank some 35 miles away from land. The minimum depth determined was 174 fm. (318 m.) and 

 altogether six soundings of less than 1000 m. (547 fm.) were obtained; four of these being less than 

 500 m. (273 fm.). Although this bank is close to the South Sandwich Group and therefore should, 

 perhaps, be considered as part of the island ridge, we might also suggest that by its position and depth 

 it is strong evidence of the trend of the connexion towards the Gierke Rocks and South Georgia. 



SOUTH SANDWICH ISLANDS TO THE SOUTH ORKNEY ISLANDS 

 In PI. XXIII several new lines of soundings can be seen on, or crossing, the ridge connecting the 

 islands of the South Sandwich Group, and these give a much more accurate representation of the 

 general outline of the ridge, certainly on the western side. Here it will be seen that the 3000 m. (164 1 fm.) 

 contour lies, in general, much closer to the islands than we had hitherto supposed and that the depths 

 less than 2000 m. (1094 fm.) have been more precisely determined. In our previous chart the six 

 southern islands (Saunders, Montagu, Bristol, and the Thule group— see Text-fig. 14) were shown as 

 being connected by a ridge at a depth of less than 2000 m. (1094 fm.), but this has now been found to 

 be incorrect. The saddle depth of the ridge between Montagu and Saunders Islands is now found to 

 be greater than 2000 m., the least depth obtained being 1354 fm. (2476 m.), and although, so far as is 

 known, no soundings have yet been taken between Montagu and Bristol Islands, similar conditions 

 may well be found to exist here. The rise of the bottom to the saddle depth between Montagu and 

 Saunders Islands, or between Saunders and Candlemas Islands is, however, almost 1000 m. (547 fm.), 

 and is in itself sufficient evidence of the connecting ridge. 



To the east of the South Sandwich Islands we have not gained so much information, except in the 

 vicinity of Saunders Island, where the 3000 m. (1641 fm.) contour can now be placed with some 

 accuracy. The two crossings farther south show a wider shelf at depths of less than 2000 m. (1094 fm.), 

 with a consequent displacement of the deeper contours. 



It will thus be seen that the connexion through the South Sandwich Group falls into three well- 

 marked areas. At the northern end there is a comparatively shallow submarine plateau surrounding 

 the islands, which stretches away in a north-westerly direction towards South Georgia. In the centre 

 we have Saunders Island, Montagu Island and, probably, Bristol Island, rising from slightly greater 

 depths. At this point also, the width of the ridge narrows considerably, the least distance between the 

 3000 m. contours being about mid-way between Candlemas and Saunders Islands. South of this the 



