Fingal and East Coast. 43 



which is nowhere quite conformable with the beds 

 of the true coal series, have also undergone con- 

 siderable disturbance. We often find re-imbedded in 

 them thin layers and unconnected masses of carbon- 

 aceous matter, which had been disrupted and torn from 

 the nether strata. 



The fact that over and upon almost every green- 

 stone hill in the district there are found fragments of fossil 

 wood, and ol clay schists and shales full of markings of 

 vegetable organisms, is one which would argue that the 

 transporting and disrupting agency of a great body 

 of water continued to operate upon the various rock 

 strata long subsequent to the deposition of the newer 

 sandstone, and the extrusion and cooling down of the 

 greenstone ; and that water was the last agent em- 

 ployed to give form to the surface of the dry land : a work 

 most probably followed and consummated by a grand, 

 gradual, and progressive upheavement of the whole mass 

 of this and the neighbouring islands. 



The sandstone which overlies the coal contains many 

 impressions of large strap-shaped leaves ; and the thin 

 layers of schist which alternate with it are often replete 

 with impressions of ferns, &c. It has generally a brown- 

 ish yellowish and somewhat mottled or streaked appear- 

 ance : it is usually coarser in grain, less compact 

 in structure, and is associated with thinner seams of 

 clay-schists, than the lower carboniferous sandstone. 



The thickness of both formations varies greatly in dif- 

 ferent districts, and at various points of the same district. 



The composition and character of the beds vary also, 

 just as we now find along the course and sinuosities of 

 our sea-shore, — in one locality, a coarse pebbly strand or 

 beach of large boulders, — in another, at no great distance, 

 a fine gravel or sand, which, after passing a neighbouring 

 rocky point, may be replaced with the finer niud or 



