OF ARTS AND SCIENCES : MAY 25, 1869. 113 



sidering that it belongs to a very ancient formation. Even where it is 

 inclined at high angles, it retains this soft texture, unless this has un- 

 dergone a change in. the immediate neighborhood of eruptive rocks. 

 x The Tadio Mountains, a picturesque range of nearly two thousand feet 

 in height, and situated about fifty miles east of Kiu-kiang, are almost 

 entirely built up of these sandstones. They are here slightly inclined, 

 and exposed in a thickness of at least two thousand five hundred feet. 

 At another place I estimated the visible portion of the formation at 

 four thousand feet ; but, as I never saw its lowest strata, nor the under- 

 lying rocks, those figures mark the minimum of the actual thickness. 



2d. Liu-shan schists. — This is a series of shales of from twelve 

 hundred to three thousand feet in thickness, which are quite character- 

 istic, being the only rocks of this kind on the lower Yang-tse. The 

 formation appears, from the descriptions given of rocks occurring south 

 of that river, to be largely distributed in eastern China, and to form a 

 valuable horizon. The shales are, for the most part, clayey and sandy, 

 and not unfrequently converted into clay-slate. The color varies from 

 yellow and red in the former to dark green and gray in the latter 

 varieties. An abundance of undeterminable remains of plants may be 

 found. This formation and the former are distinguished from all those 

 of subsequent age, by being usually intersected by numerous veins 

 of white quartz. The Liu-shan is a short but very conspicuous moun- 

 tain range, near Kiu-kiang, rising abruptly to the altitude of probably 

 little less than three thousand five hundred feet. The shales form a 

 belt at its eastern foot. 



3d. Matsu limestone. — On the Matsu-shan, a prominent hill in the 

 belt just mentioned, I observed, for the first time, the conformable 

 superposition of limestone on the Liu-shan schists. I confirmed after- 

 wards the observation in several other places. These are dark lime- 

 stones, distinguished in their lowest portion by a ribboned appearance 

 of all planes of fracture which intersect the stratification. It is caused 

 by the predominance of silica in alternate layers. The main body of 

 the limestone shows a certain brecciated structure and a dolomitic ap- 

 pearance. Chert is abundant, but I found no characteristic fossils. 

 The thickness of the formation is at least two thousand feet ; but as I 

 never saw distinctly its upper portion, this figure may be too low. The 

 deposition of these strata was followed by, — 



4th. A period of great disturbances and outbreaks of granite. — The 

 three formations which I have mentioned compose long ranges of 



VOL. VIII. 15 



