HO THE GEOLOGY OF 13RIDPOUT. 



The whole system has the usual English tilt, the strata 

 sloping downwards from "West to East, so that, as we pass 

 along in this direction, we come regularly upon higher and higher 

 beds. Here and there, however, the succession is interrupted by 

 " Faults." This general tilt in the stratification of English rocks 

 suggests that the granite hills of Cornwall, and the Archaean 

 mountains of Wales and Cumberland, are the surviving relics of a 

 mountain range which must have rivalled the Himalayas or the 

 Andes, so that once a large portion of the whole island formed 

 part of the Eastern slope of such a range which stood between 

 it and the deep Atlantic Ocean. These Palaeozoic rocks contributed 

 at a still early period to the conditions under which the 

 sedimentary deposits of the Mesozoic Era were laid down. For 

 instance, the New Ked Sandstone probably tells us of a period 

 when the strata were laid down in a large inland salt lake, like the 

 Caspian Sea ; while the " Liassic and Oolitic formations were 

 sediments laid down in warm seas surrounding an archipelago of 

 which Dartmoor, "Wales, and Cumberland formed some of the 

 islands." These islands would, in many cases, be surrounded by 

 coral reefs, like those now found in the Pacific Ocean, and had a 

 flora and fauna not unlike that found in Australia. For the 

 deposition of most of the Liassic strata we further require the 

 existence, perhaps in the North Atlantic, of a large continent, 

 whose rivers, after running over extensive flats, where they would 

 deposit their gravel and sand and carry on only the finer mud, then 

 emptied themselves into a sheltered sea where this mud would 

 quietly settle. Such a condition now exists on the eastern shores 

 of Asia. For the succeeding Oolitic epoch we may have had a 

 more open coral sea, extending over the greater part of Europe, 

 where the sediments were formed almost exclusively by the 

 grinding down and cementing together of the dclris of the 

 habitations of the industrious coral polype. But at different place* 

 formations of very different lithological character would be taking 

 place at the same time, and the Jurassic System, which extends 

 <>v.-r a considerable portion of France, and underlies the great plain 



