COAL-FIELD OF CLACKMANNANSHIRE. 139 



the coal. The coal is 5 feet thick, with a division of 

 slate-clay. In the deptli of 80 yards, there are only 

 14 strata, all of them are of a dark colour, com- 

 posed of slate-clay and ferruginous limestone, in- 

 durated clay mixed with lime and limestones, and 

 these contain organic remains in vast abundance, 

 in particular, large cornua ammonis, belemnites, bi- 

 valve shells, from the most minute to a large size, 

 and great quantities of fossil wood. Even the coal 

 is remarkable in its texture and quality, and, when 

 burning, has the smell of rotten wood, when placed 

 in a fire. Above the strata exhibited in the section, 

 and more in the line of dip, thin beds of blue-coloured 

 limestone first occur, and above these a -very thick 

 bed of soft yellow-coloured sandstone. In the sand- 

 stone, a particular bed is found about 18 inches 

 thick, approaching in its texture to compact quartz, 

 having a conchoidal fracture ; under this is a very 

 soft sandstone, containing casts of small bivalve 

 shells. A section of this coal-field is represented 

 Plate V. Fig. 4. This coal lies closely adjoin- 

 ing mountains of red granite. 



In the section of the Clackmannanshire coal- 

 field, the strata of the mountains are drawn ac- 

 cording to the exact angle at which they are found 

 at the surface ; but there is an important fact in 

 a geological point of view, which has yet to be as- 

 certained, which is, whether the greenstone and 

 other rocks of these transition mountains, form a 

 curve line somewhat parallel to the curvature of 



