on the Raised Beach in Barnstaple or Bideford Bay. 285 



low-water sands. The two sets of phenomena generally occur together, so 

 that one becomes an indication of the other. 



On the coast of Cornwall, wherever we meet with low-water sands of any 

 extent, they are drifted by the fierce western gales over all the neighbouring- 

 cliffs, and, in course of time, have, in some places, converted whole parishes 

 into deserts. After what has been said, we need not be surprised that these 

 drifted sands should chiefly occur along those parts of the coast, where raised 

 beaches most prevail : in short, the two things are generally found together. 

 This fact misled some of the early writers in the Transactions of the Royal 

 Geological Society of Cornwall*, who attributed the raised beaches themselves 

 to the blown sand, under which they, as well as the older rocks, were partially 

 buried — a very great mistake, though quite natural at the time when it was 

 made. Dr. Boase, we believe, had the merit of first pointing out this error f . 



The conclusions from these facts are obvious, and in perfect harmony with 

 our observations on the beach and shingle of Barnstaple Bay; both as respects 

 their structure and their occurrence in the mouth and seaward flanks of an 

 estuary, so much covered by blown sands. 



The elevation of the northern side of Barnstaple Bay, makes it almost cer- 

 tain that the south side must also have been affected by a similar movement ; 

 and in our reasoning respecting the " Popple-Bank," and the configuration 

 of the neighbouring country, we have assumed that both sides have been 

 raised above a former level, by a similar movement. But, at the time of our 

 rapid passage along the cliffs south of Rocks Nose, we were not aware of the 

 existence of any phenomena on the northern shore of the bay, or, indeed, on 

 any portion of the east coast of Devon, such as we have now described ; and 

 hence we omitted to look out for any direct proofs of elevation. Again ; the 

 great elevation of the coast line, extending to Baggy Point, could hardly have 

 taken place without simultaneously affecting the portions of North Devon and 

 West Somerset, which form the southern shore of the Bristol Channel. 

 There, however, we found no traces of any raised beaches, though our atten- 

 tion had been previously drawn to them. Their absence is, however, easily 

 accounted for, by the very abrupt form of these bold cliffs, and the deep seas by 

 which they are washed ; which are so adverse to the formation, and permanent 

 elevation, of extensive shelly and sandy deposits, like those above described. 



The raised beaches to which we have alluded, in South Devon and Corn 

 wall, have been stated to indicate an elevation of the land, varying from 10 to 

 40 feet ; but our case, in Barnstaple Bay, gives a maximum rise of 60 or 70 

 feet, indicating a greater intensity of elevatory movement as we proceed to 

 the north. If we ascend the estuary of the Severn, and follow that river up 



* Trans. Roy. Geol. Society of Cornwall, vol. i. p. 4. t Ibid., vol. iv. p. 260. 



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