494 MR. H. M. BECHER ON CFPRIFEROTTS 



40. On some Ctjpeiferotjs Shales in the Province of Hon-peh, 

 China. By H. M. Becher, Esq., F.G.S., A.B.S.M. (Eead 

 June 23, 1886.) 



In the month of July 1885, the writer was asked to accompany a 

 Chinese gentleman, proceeding from Shanghai, to visit certain 

 deposits of copper-ore reported to be very rich and extensive, and 

 occurring on some property up the Tangtse river. Specimens of the 

 ore had been sent to Shanghai and were given to the writer for in- 

 spection. These consisted of mixed ore of copper of dark brown 

 colour, being mostly impure oxides with a little unchanged sulphide 

 permeated by streaks. of carbonate. The mineral was very heavy, and 

 showed by a rough test about 70 per cent, of metallic copper. The 

 most interesting feature, however, was the external appearance of 

 the pieces, one of which was intact as taken from the earth near the 

 surface, showing a striking resemblance to the well-known form of 

 petrified wood, and suggesting the possible association of organic 

 agency in its origin. This peculiarity of course dispelled the first 

 assumption of large veins, though adding to the interest of inves- 

 tigating the mineral source, which proved to be near the open Port 

 of I-Chang, on the Yang-tse-Kiang, about 1000 miles from the sea. 

 The country surrounding I-Chang, on the western border of the 

 province of Hon-peh, is very mountainous, being on the confines of 

 the extensive ranges through which the river Yang-tse-Kiang here 

 emerges from its eastward course through the province of Setchuan. 

 The low hills in the immediate vicinity of I-Chang are composed 

 of reddish sandstone and conglomerate beds dipping very slightly to 

 S.E. ; but the higher mass of hills to the west is of Lower Palaeo- 

 zoic and Carboniferous (?) rocks, in which thick beds of limestone 

 are most conspicuously prominent, rising to a height of 5000 feet 

 above the river. Thus, going westwards from I-Chang, at a distance 

 of about ten miles, the limestones appear from under the sandstone 

 series, the lowest beds of the latter consisting for the most part of 

 limestone and quartzite pebbles, while peculiar beds of brecciated 

 calcareous conglomerates overlie the blue-grey crystalline limestone, 

 almost horizontally, to a thickness of some hundreds of feet. 



The relative position of these rocks is not quite distinctly evident, 

 as, though the Limestone series is proved by its fossils to be of 

 Palaeozoic (presumably Precarboniferous) age, and is overlain to the 

 westward by a great shale series, which in some parts contains coal- 

 bearing measures, it is not certain whether the sandstones (con- 

 taining no coal) to the eastward are conformable or contempora- 

 neous with the said shales, their lithological character being entirely 

 different. Each of these three series is of great thickness, i. e. many 

 thousands of yards, forming high cliffs, gorges, and sheer declivities, 

 according to the relative nature of the rocks and the circumstances of 

 denudation. The upper beds of the Great Limestone, when they 

 begin to give place to the shales, contain several bands full of 



