SPORT AND SCIENCE ON THE 



The gneiss continued as far as Kuan-t'ung-pu 

 (about 20 miles N.N.W.). West of this place 

 igneous rock prevails, an immense lava flow 

 forming a plateau some ten miles wide (length not 

 ascertained, but considerable). The basalt, which 

 marks the eastern limit of the North Shansi basalt, 

 is typical of the same, being of a dark blue-grey 

 colour, with air holes, usually lined with spar and 

 containing crystals of hornblende. In places 

 where the surface of the plateau is bare of soil 

 the basalt shows distinct hexagonal cleavage, 

 indicating columnar structure beneath. This lava 

 flow, judging from the general contour of the 

 country, is roughly from north to south. The 

 plateau ends abruptly on its western side in a 

 deep river valley, running from north to south. 

 ^Vestward other lesser plateaux occur, however, 

 and travelling along the river valley, which now 

 runs east and west, fine examples of columnar 

 structure are to be seen, notably near Fen-cheng. 

 At this place good clay occurs, enabling extensive 

 pottery work to be carried on. 



The volcanic formations continue from here 

 all the way to the T'ai Hai. North of this lake 

 the mountains are entirely of granite as far as 

 Mei-te-erh (Mei-teul), at the edge of the K'uei- 

 hua-ch'eng plain. 



Some of this granite, notably that occurring 

 up the valley east of Mei-te-erh, contains large 

 quantities of garnets, some of which are as large 



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