136 COAL-FIELD OF CLACKMANNANSHIRE. 



This range of the Ochill Mountains in Clackman- 

 nanshire, besides veins of iron-ore, contain veins 

 filled with various metals. 



In the clinkstone porphyry of the Wood-hill, re- 

 presented in the section, a rich vein of Silver was 

 wrought many years ago, and silver extracted to the 

 amount of L. 60,000. Along with the silver-ore, 

 peach-blossom coloured Cobalt- ore was found in 

 abundance. Veins of copper have been wrought to 

 the westward, at Blairlogie ; and particularly of late 

 at Airthry, where the vein was found in a rock of 

 dark brown- coloured trap-tuiF. Veins of lead have 

 also been wrought to the eastward, in the Gloom 

 Hill at Castle Campbell. 



I have here to remark, that I have examined mi- 

 nutely the coals and accompanying strata imme- 

 diately adjoining the Ochill Mountains, and found 

 that the coal, even within a few fathoms of the 

 mountain-face, is of good burning quality, similar 

 to the coals found in the south part of the coal-field. 

 Fine shistose micaceous sandstone is also found 

 near the mountain-face, with common clay iron- 

 stone, abounding with organic remains of reeds and 

 bivalve shells. The only distinct difference to be 

 observed in the coal strata at this place, from the 

 strata in the south part of the field, is, that several 

 of the thin beds of sandstone are exceedingly hard, 

 and so close-grained, that they have the appearance 

 pf compact quartz ; but this circumstance occurs in 

 other coal-fields, particularly in Glamorganshire, 



