Flora of N'arcoudam and Barren Island. 67 
miles east-sonth-east of Rutland Island, and the same distance due east 
of the opening, Duncan Passage, between Rutland Island and Little 
Andaman. The rock appears above the surface, and no more ; but though 
so much smaller as a suhaerial peak than Barren Island or N’arcoudam, 
as a submarine peak it is evidently larger than either, since its summit 
appears as a long narrow bank that carries from 15 to 80 fathoms of 
water; this bank does not extend to the east or the west for more than 
two miles from the Rock, hut towards the south extends at least 10 
miles, to the north more than 20 miles. Beyond the edge of this hank—■ 
the Invisible Bank of the Admiralty maps—the lead sinks at once into 
deeper water. The Bank itself has been carefully surveyed hut of the 
absolute depths of the soundings just beyond we know little or nothing, 
so that though this survey is invaluable to navigators, from a hydrogra¬ 
phical point of view it leaves much to be desired. Meagre however as 
its details are it shows that the soundings are deeper towards the east, 
south, and west than they are towards the north. The following Table 
indicates the soundings shown in the Admiralty maps :— 
Table III .—Soundings in the vicinity of Flat Rock. 
General direction of 
LINE OF SOUNDINGS. 
Distance in miles from 
ROCK. 
Depth in fathoms. 
N. N. E. 
1 
14 
N. N. E. 
10 
25 
N. N. E. 
13 
27 
N. 
5 
38 
N. 
15 
80 
N. W. 
5 
16 
N, W. 
10 
59 
N. W. 
15 
168 
W 
10 
90 (no bottom.) 
W. 
35 
600 
s. w. 
3^ 
78 
s. s. w. 
8 
35 
s. s. w. 
16 
200 (no bottom.) 
S. E. 
2 
16 
S. E. 
7 
48 
S. E. 
12 
200 (no bottom.) 
Along the east side of the bank none of the soundings made have 
touched bottom, but they show that the edge drops into deep water 
within 5 miles of a line running from south-south-west to north-north-east 
271 
