Q.26 



ILLUSTRATIONS OF THE 



foft and flexible, flnce their complete formation 

 it will be fonml impoflible to deny their having 



K 



been foftened by the application of heat. 



204. The fecond concliiiion, alluded to above 

 refiilts from a property, which belongs very ge- 

 rerally, if not iiniverfally, to the inflexions of 

 ttie ftrata. This confifts in their curvature 

 being fimple, or in one dimenfion only, like a 

 cylindric fuperficies, not double, or in two di- 

 menfions, like the fuperficies of a fphere or 



fpheroid. This may be otherwifc expreffed, 

 by faying, that the fe6lions of the bent ftrata, 

 by a horizontal plane, are 



ftraight lines, 



pa- 



rallel to one another. On this account, every 

 fuch ftratum feems as if it were bent over an 

 axis, and the axes of all thefe different bendings, 

 for a great extent of country, are nearly paral- 

 lel. 



The truth of this is evident, where the ftrata 



m 



are feen both tranfverfely and longitudinally. 

 It holds remarkably of the primary fchiftus on 

 the coaft of Berwickfliire 1 where the beds of 



7 



4 



rock, if cut tranfverfely, by a vertical plane, 

 exhibit the figures of very complicated curves, 

 with various tnaxhiia and minima^ and points of 

 contrary flexure ; but, if they are cut by a ho- 

 rizontal plane, the fedlion will produce nothing 



but ftraight lines, nearly parallel. 



205. The 



