OF CREATION. 107 



rents of ancient lava, heaps of erupted ashes, and rocks 

 chemically changed by the intrusion of heated vapours 

 charged with gases. In others, enormous cracks 

 extending for many hundred yards, or even for miles 

 together, may be traced in the more brittle rocks ; and 

 the rocks themselves have been burnt as in a furnace 

 by the boiling and bubbling mass of molten lava 

 which has been poured from beneath into such wide 

 fissures. Sometimes extensive tracts, where the rocks 

 are thinner and tougher, have exhibited these cracks 

 in systems of hundreds in number parallel to one ano- 

 ther ; while here and there the intense fiery action 

 from beneath has thrown up the surface into blisters 

 and domes, which are often fractured at the top, and 

 thus reveal the history of their elevation. Still more 

 frequently, also, the irresistible subterranean force has 

 snapped asunder the strata, as a violent blow would 

 pierce through a few folds of paper, and one side of 

 the broken bed has been lifted high in the air, or has 

 sunk into a deep hollow beneath. And if, as hap- 

 pened occasionally, the force was not sufficiently ener- 

 getic to break up in this way the whole group of over- 

 lying matter, it might yet effect a no less striking 

 result, raising up the strata upon a line or on a point, 

 and producing a saddle-shaped or a dome-like eleva- 

 tion, according to the circumstances of the case. 



All these effects, and all of them on the grandest scale, 

 were produced in some way or other upon many of the 

 old rocks towards the close of the first epoch of crea- 

 tion ; and every Geologist, familiar with the structure of 

 our own island, could readily point to abundant exam- 

 ples of each particular disturbance above alluded to. 

 Every coal-field is so split asunder and broken into 



