74 TOWN GEOLOGY. [m. 



It is reasonable, therefore, to suppose, that the 

 Bunter in England was dry land, and therefore safe 

 from fresh deposit, through ages during which it was 

 deep enough beneath the sea in Germany, to have the 

 Muschelkalk laid down on it. Here again, then, as 

 everywhere, we have evidence of time time, not only 

 beyond all counting, but beyond all imagining. 



And now, perhaps, the reader will ask If I am to- 

 believe that all new land is made out of old land, and 

 that all rocks and soils are derived from the wear and 

 tear of still older rocks, off what land came this enor- 

 mous heap of sands more than 5,000 feet thick in places, 

 stretching across England and into Germany ? 



It is difficult to answer. The shape and distribu- 

 tion of land in those days were so different from what 

 they are now, that the rocks which furnished a great 

 deal of our sandstone may be now, for aught I know, a 

 mile beneath the sea. 



But over the land which still stands out of the sea 

 near us there has been wear and tear enough to account 

 for any quantity of sand deposit. As a single instance 

 It is a provable and proven fact as you may see 

 from Mr. Ramsay's survey of North Wales that over 

 a large tract to the south of Snowdon, between Port 

 Madoc and Barmouth, there has been ground off and 

 carried away a mass of solid rock 20,000 feet thick ; 

 thick enough, in fact, if it were there still, to make a 

 range of mountains as high as the Andes. It is a 

 provable and proven fact that vast tracts of the centre 

 of poor old Ireland were once covered with coal- 

 measures, which have been scraped off in likewise, 

 deprived of inestimable mineral wealth. The destruc- 

 tion of rocks " denudation " as it is called in the 



