FORMATION OF PRIMITIVE MOUNTAINS. 341 



and it is not surprising that crystals of quartz occur in 

 Carrara marble. In volcanic productions, this pressure 

 no longer exists, and we should find among these the 

 same phenomena which our laboratories and metallurgic 

 operations present. Following this theory, the circum- 

 stances that primitive mountains contain gypsum and 

 carbonates, and that water occurs in quartz, very readily 

 admit of explanation. And with regard to this latter 

 phenomenon, the observations detailed by Sir Humphry 

 Davy afford an additional confirmation of the theory in 

 question. 



We may explain in the same manner another pheno- 

 menon, which is more in connection with the present 

 state of our globe. Many observations shew that the 

 sea stood formerly at a much higher level than it does 

 at present. The water of the sea expands, if the tem- 

 perature be elevated more than the land. Admitting 

 that the surface of the earth has a temperature of 80 of 

 Reaumur, and that the mean depth of the sea may be 

 96,000 feet, the height of the sea would then be 4000 

 feet higher than it is at present. If we suppose, as may 

 be done without committing any great error, that the 

 expansion of the primitive mountains is equal to that of 

 glass, and that they have been at a temperature of 200, 

 and even at a much lower one, the water of the sea 

 would cover the secondary mountains, in which we find 

 the remains of marine animals. This explanation of the 

 former height of the sea appears very simple, because 

 the elevated temperature of the earth may have resulted 

 either from its original state of fluidity, or from a geo- 

 logical revolution, which has destroyed, at the same time, 

 the organic beings of a former period. 



