Physical Geography. 109 



the sediments might by degrees get into a condition to 

 get coloured red in the manner previously mentioned. 

 We have a case in point in an old inland sheet of water, 

 as shown by the Eed Marls of the extinct Miocene lakes 

 of Auvergne in Central France. 



The uniformity of action here sketched may present 

 a difficulty to some geologists, seeing that on the 

 borders of South Wales the Upper Old Ked Sandstone, 

 over a large space, overlaps the lower strata till they lie 

 directly on Silurian rocks, and the same is the case in 

 parts of Scotland. But on consideration these circum- 

 stances do not present any real difficulty. If the great 

 hollow in which the Dead Sea lies, were gradually to 

 get filled with fresh water, and the whole by degrees 

 became silted up, 1,300 feet of strata would be added 

 above the level of the present surface, and the upper 

 strata all round would overlap the lower, apparently 

 much as the Old Ked Sandstone strata do in Wales and 

 the adjoining counties. If the Caspian and other parts 

 of the Asiatic area of inland drainage got filled with 

 fresh water, the same general results would ensue. 



Like the recurrent circumstances that have attended 

 the rise and falls of empires through all historical time, 

 so geological history has often more or less repeated 

 itself, somewhere or other on the surface of the earth ; 

 and in this modern phase of Asiatic physical geography, 

 it seems to me that we may have, so far as it has gone, 

 a repetition of events, which, with minor variations, 

 have happened again and again, in old-world geological 

 epochs, the history of which I shall by-and-by have to 

 record. The farther off geological records recede, like 

 inscriptions in an unknown tongue, the more difficult 

 are they to decipher ; the nearer they come to our own 

 day, they are often more easy to read. 



