Dr. Mac Culloch on the Granite Tors of Cornwall. Q^ 



moveable in Cornwall. I made an attempt to ascertain its weight 

 by measurement. It may without much inaccuracy be resolved 

 into two frusta of pyramids, on a common trapezoidal base, tlieir 

 union forming an irregular four-sided prismatic figure, 17 feet in 

 length, and 3^^ feet in circumference about the middle part. 

 Comparing the solid content of the stone, as deduced from this ap- 

 proximated measurem.ent, with the sp. gr. of the granite of which it 

 is composed, the weight appears to be 65,8 tons, a deduction if not 

 precise, sufficiently accurate at least to satisfy general curiosity. 



It would be superfluous to combat the opinion of those, who like 

 the Iconocolasts of Cromwell's time, in the instance of the rocking 

 stone of Merramber, fancied these stones to be the productions of 

 art directed to religious purposes. The accidental coincidences 

 which give rise to their formation, will be considered when I have 

 reviewed the other tors which are the subject of this paper. 



The Cheese- wring, (PI. IV.) of which the second drawing is a 

 representation, occupies the highest ridge of a hill to the north of 

 Liskeard, one of that collection of hills which decline from Roueh- 

 tor, and Brown-willy, and which form the most elevated part of 

 Cornwall. The summits of all these hills are covered with granite 

 cairns in different states of ruin and disintegration, and their sides are 

 strewed to great distances with the bowlders which have fallen from 

 them at different times. 



The migration of stones is here readily to be traced upon a scale 

 easily comprehended The granite of which these hills are com- 

 posed is well known, and has been often described. 



It is not far from the Cheese-wring that the first traces are found 

 of the asbestos and steatites which are known to be so abundant and 

 conspicuous in the parish of St. Cleer, 



The inspection of the drawing will show that this remarkable cairn 



