40 NOETLING : PETROLEUM IN BURMA 



viscous mud spurted out periodically from a small hole, and with 

 such force, that it was thrown up in the air. A stream of mud 

 apparently issued from this vent, whose exact position could not be 

 traced owing to its being hidden below mud. Another parasitic 

 cone at the northern end was dry. 



The general shape of this cone has not changed, but its activity 

 exhibited great variations. From being nearly extinct in 1888 it. 

 rose to a state of comparative activity in 1895, but since that time it 

 has quieted down considerably. 



JVo. 5. — This is the most remarkable of all the mud volcanoes near 

 Minbu ; it is the largest and highest amongst them and is at the same 

 time the most active. It has undergone various changes since 1888 ; 

 measured from the northern foot of No. 4 it is about 300 feet to the 

 north of that cone, and rises in a rather steep cone of about 40 to 

 45 feet in height on a very gently inclined and broad basis. 



In 1888 it formed a single cone with a crater of about 6 feet in 

 diameter, which was filled with a very viscous mud in which rose 

 enormous bubbles of an inflammable gas with a strong petroliferous 

 odour. The rise of the gas bubbles produced a gurgling noise, then 

 the surface of the mud slowly rose in a huge bubble which fell back 

 on bursting, producing a kind of concentrically rippled surface on the 

 mud which fills the crater. The temperature w3s 76 F. 



To the south-east were two smaller vents with watery mud at the 

 same temperature. 



In 18S9 the same vent was as active as before. I noticed, how- 

 ever, a remarkable occurrence ; within 24 hours the level of the mud 

 which filled the crater rose by about 6 inches. The first day when 1 

 visited it, the surface of the mud was about 6 inches below the rim of 

 the crater ; on the second day it had risen and filled the crater to the 

 rim; the smaller vents, on the south-eastern side were very 

 active. 



In 1895 the smaller vents had combined and formed a second 

 main crater towards south-east, separated from the older crater by a 

 low saddle in which there was a third vent (See plate III). The new 

 ( 86 ) 



