9 o SIEGE OF THE SOUTH POLE 
a great mountain like a tent divided vertically into two 
parts, one side white with snow, the other very dark; 
this was taken to be the island in question and was 
coasted within a mile of the land, and next day a second 
island was seen, not so high as the first, and about ten 
miles to the northeast. Several days were lost waiting 
for the sun to appear to make an observation possible, 
and at last the positions were obtained as 53 0 15' S. and 
4i°4'W. of Cadiz for the first island, and 52 0 37' S. 
and 41 0 26' W. of Cadiz for the second. The cruise of 
the Atrevida was a piece of simple marine surveying, of 
no importance in exploration ; but it is mentioned here to 
show how extremely uncertain the positions assigned to 
discoveries at sea often are, even in localities far re- 
moved from the atmospheric illusions peculiar to the 
polar seas. 
