MODERN GEOLOGY 



the more solid parts of the mass, as it rose, and envel- 

 oped by the softer parts), its concretionary nodules 

 and new minerals, etc. 



" Beneath this, the granite which had been simply 

 disintegrated was again solidified, and returned in all 

 respects to its former condition. The temperature, 

 however, and with it the expansive force of the in- 

 ferior zone, was continually on the increase, the caloric 

 of the interior of the globe still endeavoring to put itself 

 in equilibrio by passing off towards the less-intensely 

 heated crust. 



"This continually increasing expansive force must 

 at length have overcome the resistance opposed by the 

 tenacity and weight of the overlying consolidated 

 strata. It is reasonable to suppose that this result 

 took place contemporaneously, or nearly so, on many 

 spots, wherever accidental circumstances in the text- 

 ure or composition of the oceanic deposits led them to 

 yield more readily ; and in this manner were produced 

 those original fissures in the primeval crust of the earth 

 through some of which (fissures of elevation) were in- 

 truded portions of interior crystalline zones in a solid 

 or nearly solid state, together with more or less of the 

 intumescent granite, in the manner above described; 

 while others (fissures of eruption) gave rise to extrav- 

 asations of the heated crystalline matter, in the form 

 of lavas that is, still further liquefied by the greater 

 comparative reduction of the pressure they endured." 



The Neptunists stoutly contended for the aqueous 

 origin of volcanic as of other mountains. But the 

 I were with Scrope, and as time went on it came 

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