5 o NATURAL HISTORY of N RJFAT. 



this cavern fome days after, on my return from Nordal, when f 

 ventured further in, though not fo far as two men whom I had 

 with me. We then perceived, by the help of a lanthorn, through 

 an aperture under our feet, that the ftream had made itfelf an- 

 other flat and fmooth bed of little Hones, or a gravelly bottom, 

 like that under which it now runs, confequently in time, it will 

 likewife penetrate through this new vault, which will then become 

 its roof, and thus in another bottom, proceed to lay the founda- 

 tions of another new vault : 



Tantum a?vi longinqua valet mutare vetuftas. 



However eafily thofe caverns, through which there is a water- 

 courfe *, may be accounted for, yet it is more difficult to explain 

 the origin of the many dry caverns and fecret paflages in the 

 rocks, like that of Dolfteen, of which more inftances might upon 

 inquiry be found in other mountains. The opinion that carries 

 Ithe greater! weight with me, is that of Woodward, in his Theory 

 of the Earth, p. 85, that the whole mafs of terreftrial matter, 

 after its diflblution by the deluge, and its fubfequent reunion, 

 was foon after, when dried and hardened, by fome fecret caufe in 

 the earth itfelf (a univerfal earthquake, or the like) again fepa- 

 rated and thrown into fuch confuflon, that the feveral ftrata, or 

 layers, funk in fome places, and rofe in others : this naturally 

 gave the furface of the earth the appearance of a crackt or mat- 

 tered building, with many chafms betwixt its ruins, till at length 

 the earth mall be entirely levelled. 



SECT. VII. 



Effeasofthe However true it be that this opinion of Woodward deferves the 

 Suti^ntnd preference, beyond any of the conjectures of Burnet, Whifton, or 

 thewe / other theorifts on the effe&s of the deluge, yet it has not been 

 which'thdr exempt from opposition, and particularly is combated by Elias 

 £3£j££iy Camerarius, and but lately by Mr. Buffon. My reafon for adopting 

 diicermbie. it here, is, that of all others, it moft facilitates the difcovery of 

 the origin, not only of the cavities, but of the mountains them- 

 felves : He does not deny, as Burnet does, the exiftence of moun- 

 tains and hills before the deluge, but is of opinion, that they 



* Of this kind is that fa remarkable cavern in the Peak in Deibyfhire. 



were 



