238 THEOKY OP THE EARTH. 



respects of its existence ? All that can be admit- 

 ted in this matter is, what some moderns have 

 thought, that astronomy was among the number 

 of the sciences preserved by those whom this catas- 

 trophe dispersed, 



Exaggerations relative to the Antiquity of certain 

 Mining 1 Operations. 



The antiquity of certain mining operations has 

 also been much exaggerated. A very late writer 

 has imagined, that the mines of the island of 

 Elba, judging from the rubbish carried out of 

 them, must have been wrought for more than 

 40,000 years ; but another author, who has also 

 examined this rubbish with attention, has redu- 

 ced the period in question to -a little more than 

 5000 years, * and this even on the supposition 

 that the ancients did not extract annually more 

 than a fourth part of the quantity of ore now 

 wrought. But what reason could there be to 

 suppose that the Romans, for example, who con- 

 sumed so much iron in their armies, derived so 

 little advantage from these mines ? Moreover, if 

 these mines had been wrought for even 4000 years 



* See M. de Fortia d'Urban's History of China before the 

 Deluge of Ogyges, p. 33. 



