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. 
Westward 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 Fén-chéng. 
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-té-érh (Mei-teul), at the edge of the Kuei- 
hua-ch’éng plain. 
Some of this granite, notably that occurring 
up the valley east of Mei-té-érh, contains large 
quantities of garnets, some of which are as large 
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