88 Records of the Geological Survey of India. [vol. vi. 
deep, lias a circular bottom, which is filled with sand. This appears to have been the last 
crater formed on the island. 
The two principal edges of the depression strike to north-west, south-east; they consist of 
ash permeated with fibrous gypsum (selenite) ; numerous cracks and fissures occur in this 
part of the hill, and the ground is hot. On turning over the surface, the sides of these 
cracks are found to be encrusted with sulphur, resting upon the rugosities of which small 
detached crystals of the same mineral were not uncommon. From the highest point on the 
northern edge a thin column of white vapour and sulphureous fumes is slowly poured forth. 
Even when standing in its midst, the fumes did not prove so irritating a might have been 
expected. 
On the southern side of the crater there is some solid lava in situ, and on the west there 
is a peculiarly shaped mass which forms a conspicuous object from below. Some of the lava 
here has a reddish matrix and is somewhat vesicular. I also found some basalt, the outer 
surface of which was weathered into a white crust. 
It seems probable that the nucleus of the cone is solid rock to a considerable extent, the 
ashes seen at the surface being only superficial. 
By following water channels when they were to be found, and glissading over the ashes, 
the return to the base of the cone was effected speedily and without much difficulty. 
By a small watch-aneroid supplied with a Vernier scale for feet, the height of the cone 
is 950 feet; but as one heavy storm of rain had passed, and clouds portended another, I am 
willing to believe that owing to the atmospheric disturbance the observation was not trust¬ 
worthy, and that from 975 to 980 feet given by Lieutenant Heathcote, Dr. Liebig and others 
is the true elevation. The temperature on the top was 83°. 
The diameter of the base of the cone is 2,170 feet according to Lieutenant Heathcote. 
The slopes of the cone incline, according to my ohservation, at angles varying between 30° 
and 35°. Blair gave it at 32° 17', or about the mean of these two. Other observers say 40° 
to 45°, hut the photograph of the cone shows that the former is correct. 
Dr. Liebig has discussed the question of the amount of sulphur obtainable on the island. 
He seems to think the chances of finding a permanent supply very doubtful, but recom¬ 
mends a preliminary trial. 
Considering the great expense which keeping up constant communication with the 
Andamans and the superintendence of convict labour would involve, I cannot see that 
there is any prospect of the collection and refining of the sulphur being made to pay. 
So far as is known, the substance occurs only at the summit of the cone, though, doubt¬ 
less, if the right places could be found, it does also occur lower down. But in such places, 
it could only be as an old deposit which, on being worked out, would not be replaced again. 
On the summit the deposit, so far as I could see, proceeds very slowly, certainly not with 
sufficient rapidity to keep laborers constantly employed. 
Naekondam, Lat. 13° 24'; Long. 94° 12 1 . 
History and previous notices .—So little has been published regarding this island that a 
few lines will suffice to dispose of all that has ever been recorded regarding it. 
In 1795 it was passed by Colonel Symes* when on his voyage to Rangoon, whence he 
started on his embassy to Ava. He speaks of it as “ a barren rock rising abruptly out of 
the sea and seemingly destitute of vegetation.” 
Embassy to Ava, Vol. I, 1827, p. 167. 
