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II. On the Vertical Position and Convolutions of certain Strata, 

 and their relation with Granite, By Sir James Hall, 

 Bart Pr. R. S. Ed. & F. R. S. Lond. 



[Read February 3. 18 12. J 



THE tract of country extending across this island, from 

 the sea-coast of Galloway to that of Berwickshire, con- 

 sists, with little interruption, of that species of rock, which has 

 of late been most generally known by the German name of 

 Grauwacke. But as this rock does not differ essentially from 

 what in Cornwall is called Killas, I am disposed, in concur- 

 rence with several members of this Society, in particular with 

 Mr Allan, who has of late been in Cornwall, and has paid 

 particular attention to that subject, to reject the uncouth term 

 Grauwacke, and adopt that of Killas, as being more congenial 

 to our language. 



The continuation is so unbroken, that I believe it would be 

 practicable to walk from one sea to the other, without tread- 

 ing upon any rock but killas ; and as its character is identical 

 throughout, we seem to be authorised, in every view of mine- 

 ralogy, to look upon the whole as one with respect to origin 



and 



