besides Pegmatite, Felspathic and Micaceous rocks, and Gneisses were plentiful 

 in the valley-bottoms on either side of the pass. 



With my limited knowledge, it would be hopeless to attempt a full 

 description of the co;nplicated structural formation of the Chiao-ch'^ng Shan 

 district : the most I can do is to mention the names and the positions of the 

 rocks which I noticed. So far as I could gather, these mountains, like those 

 in the Ning-wu district, are formed by a great fold, the softer rocks of which 

 have been denuded, thus laying bare the Plutonic rocks. The tops of the 

 peaks and ridges are undoubtely of granite, which varies in colour from grey 

 to pink, and in texture from a fine to a coarse grain. The summit of Mo-6rh 

 Shan (9,200 feet), the highest peak in the district, is in the form of a hugh cone 

 of grey granite, slowly breaking up into large blocks — roughly cubical — many 

 of which lie scattered down the mountain's side. Slightly curved joints — 

 very noticeable in our illustration (Plate 55) — cut across the summit, and 

 appear to form an anticline. On the next highest peak Yun-t'ing Shan, red 

 granite appears, as well as the grey. To the north, the peaks and ridges seem 

 to be composed of gneiss and other metamorphic rocks, with ribs of granite 

 here and there. The valley-bottoms are strewn with boulders, and stones 

 of all kinds of crystalline rock ; the minerals quartz, mica, and felspar 

 predominating. 



On descending the western slope of this great ridge, which divides the 

 basin of the F6n Ho from the Yellow River, we soon reached again the beds 

 of shale and sandstone. They present here features similar to those east of 

 Chiao-ch'eng Shan. Huang4'u is very widely distributed, and in many places 

 hides all other formations by extending right down to the valley-bottoms. 



At a distance of about fifteen miles from the Chiao-ch'^ng Shan range, we 

 crossed another small divide, the summit of which was composed of shale 

 protruding through the Huang-Vu. Between here and the next pass — about 

 twenty miles further west — lies the river valley, in which the town of Lin 

 Hsien is situated. The valleys between these three divides run from north- 

 east to south-west, eventually joining the Yellow River. 



The Lin Hsien valley is filled with vast deposits of Huang-fu so that 

 only at the ravine-bottoms is the substratum of sandstone exposed. 



One might consider the chain of mountains, which divides the Fdn Ho 

 from the Yellow River, as forming the eastern boundary of a vast flat basin, 

 which takes in the whole of Northern Shensi, and the adjacent parts of Shansi, 

 and Kansu. This basin is underlain by the Sinian Limestone, upon which 

 lie Sandstone and Shale formations, which in turn are covered by a thick layer 



121 



