234 



DISCOVERY REPORTS 



sounding. It seems most likely in the light of our experience that small bergs of " black " 

 or "bottle-green" ice have been mistaken for rocks, for these bergs, which are not un- 

 common off the mouth of the Weddell Sea, are very confusing, especially in thick weather 

 or a bad light. Several of those sighted from the " Discovery II ' might easily be mis- 

 taken for a small rock awash, had it not been for the knowledge that the echo soundings 

 at that moment were well over 3000 m. 



The most interesting search we carried out was for Thompson Island which was 

 supposed to lie to the north-eastward of Bouvet Island. This island was first reported 



East Lorijjitude 



Fig- 5- 

 Area covered in the search for Thompson Island and the Chimneys. Black dots are points at which ship's 

 position was accurately fixed. Shaded area represents the limit of visibility from the crow's nest. The figures 

 show soundings in metres. 



by Captain Norris of the whaler ' Sprightly' in 1825 as being approximately 45 miles 

 north-east of Bouvet Island. Some rocks, called the Chimneys, were reported at the 

 same time to lie about 4I miles to the south-eastward of Thompson Island. From 1825 

 until 1893 no one appears to have sighted the island, but in the latter year Captain 

 Fuller of the ' Francis Allen ' is stated to have sighted it but to have been unable to fix its 

 position on account of wind, ice and fog. Since then it has been unsuccessfully searched 



