of Devonshire and Cornwall, 151 



Alderney, and the adjoining coasts of France. If it were attempted 

 to determine the epoch when the land of Cornwall was separated 

 from the opposite coast of the Continent, and consequently the epoch 

 of the formation of the British Channel, we must, in order to dimi- 

 nish the resemblance as little as possible, fix the date of that great 

 event, immediately posterior to the deposition of the granite, a period 

 lost in the darkness of ages. 



Mean Cliff, situated a little to the E.N.E. of the Land's-end, is 

 also entirely composed of granite, and is one hundred and eighty- 

 eight feet high : at the bottom of it is a rock curiously shaped, 

 called by the inhabitants, the Irish Lady.* 



In descending from Mean Cliff to White-sand Bay, we passed a 

 small village called Escales, at the north end of which we found the 

 rocks laid bare by the sea at low water, to be compact grauwacke : 

 that rock may be traced for some distance under the sea. The same 

 common grauwacke again occurs on the sea-shore a little further to 

 the north. The point of land called Cape Cornwall, stretching out 

 to the west, and which may be considered as the western limit of the 

 northern portion of the mountain chain, is entirely composed of 

 grauwacke, although it is two hundred and twenty-nine feet high, 

 while, at the cliffs east of the cape, the same rock does not rise higher 

 than ninety-three feet. 



Advancing from Cape Cornwall into the interior of the country by 

 St. Just, many blocks of schorl rock are found scattered on this part 

 of the granitic plain, particularly amongst the rubbish of some old 

 tin mines, which are now scarcely worked. Though quartz be dis- 

 seminated in small crystals through the mass, it sometimes also 



* In the road from Two Bridges to Tavistock, in Dartmoor Forest, Mr. Neckcr re 

 marked a rock of granite, of which he took a sketch, very much like an Egyptian sphinx 

 in a mutilated state; the same resemblance occurred to us both at the same instant. 



