[ 37 J 



The obfervation of Tilas however relates only to the extreme 

 endfc, and not to toe flanks of mountains ; with refpe6t to the 

 former he remarked that the Jieepefl declivity always faces that 

 part of the country where the land lies lowefl, and the gentlefi 

 that part of the country where the land lies higheft, and that in 

 the fouthern and eaftern parts of Sweden they confequently face 

 the E. and S E and in the northern the W. The eflential part 

 of this obfervation extends therefore only to the general elevation 

 or depreflion of the country, and not to the bearings of thefe 

 declivities. 



The difcovery that the different declivities of the flanks of 

 mountains bear an invariable relation to their different afpeds 

 feems to have been firft publifhed by Mr. Bergman in his phyfical 

 defcription of the earth, of which the fecond edition appeared in 

 1773. He there remarked that in mountains that extend from 

 N. to S. the weftern flank is the Jleepeft and the eaftern the 

 gentlefi. And that in mountains which run E. and W. the 

 fouthern declivity is the fteepeft and the northern the gentleft, 

 vol. 2d. § 187. 



This affertion he grounds on the obfervations related in his 

 firft vol. § 32, namely, that i'' in Scandinavia the Suevoberg 

 mountains that run N. and S. feparating Sweden from Norway, 

 the weftern or Norwegian fides are the fteepeft, and the eaftern 



or 



