30 TRANSACTIONS OF THE [Sess. lxxx 



in order to see if that will furnish a clue as to the building 

 of the parallel divides, and the original connection between 

 the Himala3'as and the backbone of China, b}^ which means 

 the similarity in flora must have been brought about. 

 Geology is a subject which permits free speculation, and if 

 in the following notes I have abused the privilege, it is 

 because I have seen but a fraction of the country, and have 

 not gone deeply into the matter. Nevertheless, though it is 

 useless to attempt a detailed description of the region with 

 the scanty knowledge at m}^ disposal, still there are certain 

 prominent and fundamental facts which will go a long way 

 towards telling us what has happened here. 



Evidence of Geol</fpj. 



As far as I have studied the country- from the Mali 

 valley in North- West Burma to the Yangtze valley in 

 Yunnan, the mountains all trend from north to south and 

 are separated by deep valleys, which in the north and east 

 are crorges; in the west erosion has been greater than else- 

 where, and the mountains are consequently much dissected 

 but often parallel to themselves. There is plentj^ of evi- 

 dence to show that volcanic activity has, in the past, played 

 a part in the moulding of the country, though the present 

 manifestations are such as are associated with waning of 

 volcanic forces. Hot springs are abundant throughout the 

 country, and are to be seen issuing from the base of all 

 the parallel ranges ; near Tatsienlu in Western Szechwan is 

 a crater lake, and there is another in Upper Burma, while 

 at Tengyueh in Yunnan tliere is an extinct volcano of very 

 perfect form, with lava beds still intact; a second extinct 

 volcano, Mount Popa, is found in Upper Burma. Earth- 

 quake .shocks are fairly numerous in Western China, 

 Assam, and Burma, and the whole earthquake area here 

 seems to narrow southwards and eventually to tail off along 

 the volcanic line passing down the Malay Peninsula and 

 through the East Indies. The official annals of Yunnan 

 contain the records of many earthquakes, but the most 

 notable in this region are those of 1850 and 1895 in 

 Western Yunnan, and that of 1897 in Bhotan and Assam. 



In the rocks too we find evidence of volcanic activity. 



