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The structure of the Jura chain of Switzerland likewise exhibits 

 proofs of the same laws. There the crust waves closely resemble 

 those of the Appalachians — the whole chain is composed of several 

 groups of flexures, differing in their direction or strike; but the 

 waves of each group display a remarkable parallelism among them- 

 selves. Very few of the flexures exhibit actual inversion of their 

 steeper sides. It is remarkable that the steep slopes of the great 

 waves of the Jura face the Alps ; and those nearest the Alps, or on 

 the borders of the valley of Switzerland, are more compressed than 

 those on the far side of the chain, — their more inclined flanks, for 

 example in the Weissenstein, dipping even perpendicularly, or a 

 little past this, into partial inversion. This southward thrust of the 

 crests of the Jura anticlinals would seem to imply a movement 

 fr^m the north, and not from the igneous axis of the Alps, or probably 

 from both quarters, at the period of the production of the flexures. 



The Alps themselves show the same general structural phenomena 

 as the other plicated zones described, but under more complex condi- 

 tions. This much convulsed mountain system contains but few 

 waves of the open or normal type, consisting, except on its outer 

 flanks, of many very close plications of the strata. When these 

 foldings are carefully studied and structurally connected with each 

 other, the whole chain appears to be composed of two or more central 

 parallel igneous crests, and each flank of these mountain ranges 

 of a belt of closely compressed waves. Each of these plicated 

 zones or Alpine slopes displays the axis planes of its flexures dipping 

 in towards the centre of its own chain, the flexures nearest the 

 igneous axis plunging at a lower or flatter inclination than those 

 more remote. High in the slopes of the chain, where denudation has 

 removed the largest part of the originally present upper formations, 

 only the synclinal folds of these remain preserved. These are the 

 so-called V's of the tertiary and Jurassic beds, pinched in between 

 the closely folded anticlinals of the gneissic, and other older rocks. 

 The inward dip of nearly all the beds of both slopes of the Alps, 

 thus occasioned by the completeness of the folding and the outward 

 thrusting of the anticlinal parts of the flexures, is the obvious cause 

 of that fan-like feature of dip of the entire chain, which has recently 

 excited so much discussion among geologists. Cleavage of the 

 rocks, and a superinduced crystallization parallel to the cleavage 



