MINERALOGY OF THE OCHILS. 



Heavy -Spar, 



Straight lamellar heavy-spar is the veinstone of 

 the mine behind Castle Campbell, of those of 

 Alva Hill, and Airthry Hill, in all of which it 

 traverses the newer varieties of the clinkstone, 

 which approach to felspar through the greenstone. 

 They are four or six feet wide, with their out- 

 goings to the south. Dip near 45® to the north- 

 east ; but from the falling in of the roofs and other 

 accidents, it was impossible for me to ascertain 

 any particulars respecting them. It is in these 

 veins of heavy-spar, that the cobalt, silver, cop- 

 per, and lead, have been deposited. Of the two 

 first of these, I could discover no trace ; though 

 there is no doubt that both have been obtained in 

 considerable quantity. The fullest account I have 

 been able to meet with of the silver mines, is that 

 contained in Sir John Sinclair's Statistical Account 

 of Scotland, under the head Alva. Of the cobalt, 

 I have seen no published account. It appears, 

 that both these metals were found in the Alva 

 Hill. 



Copper and lead are still to be found both in 

 the mine behind Castle Campbell, and in the 

 mines of Alva. But the specimens (which alone 

 I could procure) at the entrance, are so much acted 

 upon by the weather, that I cannot venture to at- 



