and Writinga of Baron Leopold von Buck, 227 



turned towards the central chain, we find ourselves driven 

 to recognise in these, the violently-separated, widely-opened 

 edges of the fissures from which the central chain was elevated. 

 When this fissure first burst open, and when its edges were 

 puslied wide asunder by the melted mass erupted from a 

 great depth, the lateral pressure which these ascending se- 

 condary chains exercised on the strata in connection with 

 them, must have produced a multitude of secondary fissures 

 parallel to the chief one. The powerful and various move- 

 ments of the surface during the elevation of a mountain-chain, 

 combined with the unequal lateral pressure of the ascending 

 masses on the walls of their principal fissures, must have pro- 

 duced irregular and diversified altered portions of strata at 

 the edges of the secondary fissures. Where no secondary 

 fissures were found, owing to the strata being soft and yield- 

 ing, there these must necessarily occur in saddle-shaped forms 

 parallel to the fissures, or in protuberant contortions. In a 

 word, whenever the protrusion of one or more volcanic rocks 

 occurred, and caused the formation of abruptly- elevated moun- 

 tain-chains, there, in an extensive superficial space, a large 

 number of subordinate small parallel chains on both sides of 

 the principal chain must have been the consequence ; and 

 these now cover the district, and exhibit in their sections, 

 sometimes contortions, sometimes saddle-shaped arrangements 

 of stratification. 



This phenomenon has communicated to whole tracts of 

 country their prevalent physiognomy, which is made quite 

 apparent in their representations on maps ; and hence it must 

 be principally attended to in descriptive geography, in order to 

 convey a proper conception of the fundamental form of such 

 districts. The theory thus originally amply detailed by Buch, 

 to account for the formation of the irregularities on the sur- 

 face of our globe, has been everywhere confirmed in the most 

 striking manner. 



The Alps, which first gave rise to the conception of this 

 view, present an enclosed mass abruptly rising with an uniform 

 longitudinal direction, and all their parallel chains are de- 

 pendent on the great principal fissure from which the central 

 chain arose. This central fissure has, however^ operated t 



