l6 HAYDEN : GEOLOGY OF THE PROVINCES OF TSANG AND 0. 
adapted for the treatment of a specific disease or set of diseases, 
the particular bath employed thus depending on the nature of the 
malady to be treated. 
Hot springs also occur at about five miles to the north-northeast 
of Kampa dzong and at Khangma in the valley of the Nyang Chu. 
The springs of Kampa dzong are considerably hotter than any 
others known in this area: their temperature varies from 140° F. to 
175° F. and was reported in one instance to have been as much as 186^. 
They issue from the Jurassic beds in the valley of the Yaru river, and 
like those of Lachung and Yoja have a strong sulphurous smell. 
Extensive deposits of both calcareous and siliceous tufa sur- 
round the springs and sometimes take the form of a series of small 
terraces. Beautiful crystals of yellow calcite are also found in 
cavities in the calcareous tufa. 
The Khangma springs are situated on a broad river-terrace at 
about I mile below the village of Khangma on the right bank of the 
Nyang Chu. Large masses of travertine occur on both sides of the river 
and prove that the springs must at one time have been very much 
more extensive than they are at present. Very few of these springs are 
now active, but the sites of many now extinct can be traced in the 
little cones dotted about the surface of the ground. The cones of 
some of those now active are as much as four or five feet in height, 
the water bubbling up gently or lying quiescent in a small crater in 
the apex of the cone. In some instances there is no overflow although 
the water in the crater is warm. It is just possible that these 
apparently quiescent springs may be miniature geysers, but I saw 
no signs of periodic movement of the water during the short space 
of time 1 was able to devote to their examination. 
Both the Khangma springs and those of Kampa dzong rise along 
lines of fracture of the rocks, the latter springs being situated on the 
important dip-fault which cuts through the Cretaceous beds on the 
ridge behind the fort, whilst the Jurassic beds at Khangma are 
intensely folded and a fault can be seen in the hills on either side of 
the river and passing through the site of the springs. 
1 '37 ) 
