[ so 1 



iliiNCE +° We fee why on ciifFerent fides of lofcy mountains 

 different fpecies of itcnes are found, as Fallas and Sauffure have 

 obferved, 2. Sauff. § 98 1, a circumftance which Sauffure ima- 

 gined almoft inexplicable, but which Dolomieu has fince hap- 

 pily explained by {hewing that the current which conveyed 

 the calcareous fubftances to the northern, eaflern and N. eaftern 

 lides of the Alps, for inftance, was flopped by the height of 

 thefe mountains, and thus prevented from conveying them to 

 the fouthern fides, and thus the N. eaflern fides were rendered ' 

 more gentle than the oppofite, 3, New Roz. p. 425, conformably 

 to the theory here given. 



Hence 5® Where feveral lofty ridges run parallel to each 

 other it mufl frequently happen that the external fhould inter- 

 tercept the depoficions that do not furmount them, and thus 

 leave the internal ridges deep on both fides. 



Hence 6° Low granitic or other primitive hills are frequently 

 uncovered by adventitious flrata on all fides as at Phanet in 

 the county of Donegal, or are covered on all fides ; the im- 

 pregnated waters either eafily paffing over them or flagnating 

 upon them according to the greater or leffer rapidity of its ■ 

 courfe and the obflacles it met with. 



The two fold motion of the antient ocean is noticed both by 

 Buffon and Bergman, but neither of them have deduced from 



it 



