SPORT AND SCIENCE ON THE 



At Hsin-yin-tzu the valley bends northward 

 again, and subsequently continues winding in a 

 general north-easterly direction to its source. 

 From this village the outcrops are entirely of granite, 

 felsite and serpentine, no metamorphic rocks 

 occurring, till, just before Hsi-wan-tzii is reached, 

 an extensive outcrop of gneiss is encountered. 



Beyond Hsi-wan-tzu (i.e. to the east) we found 

 the mountains to be composed entirely of a dark 

 grey-brown or purple-grey trachyte containing the 

 characteristic white crystals of felspar. 



PART 6 



The Geology of the Country traversed by 

 THE Chang-sui Extension Line, North- 

 western Chihli and North-eastern Shansi 



From near Kalgan to Tsai-kou-pu this railway 

 line traverses obliquely the wide valley of the 

 Yang Ho, crossing a great mass of detritus brought 

 down from the north. After leaving Tsai-kou- 

 pu it follows a tributary of the Yang Ho, called 

 the Nan-yang Ho, and soon passes through a 

 range of mountains composed entirely of meta- 

 morphic rocks, soft mica schists greatly pre- 

 dominating. In places the schists show very 

 marked stratification. 



Beyond this the valley widens out and the line 

 no longer hugs the mountain side. Immense 



272 



