1848.] MURCHISON ON THE STRUCTURE OF THE ALPS. 239 



tains trend in the Maritime Alps, where it would, however, almost seem 

 that they bend round so as to be confluent with the Apennines and 

 envelope the great depression of Piedmont and Lombardy ; thus de- 

 scribing a grand sweep, or in other words an outward semicircular 

 line, of which the Monferrato near Turin is the last external fold. 

 It is enough for my present purpose, to show, that whatever be the 

 direction of the chief crystalline axis of any one region in these moun- 

 tains, such is the dominant strike of the flanking deposits. Now, 

 whether such axes are marked by the protrusion of granite, syenite, 

 or any other so-called eruptive rock, or are simply occupied by strata 

 which have been metamorphosed, it is manifest that some powerful 

 energy has been exerted throughout and along them, which action 

 has so affected all the sedimentary deposits on their sides, as to pro- 

 duce a parallelism to the central axes, both in anticlinal and synclinal 

 folds and in deep longitudinal fissures. If the valuable detailed maps 

 preparing by M. Studer were published, this fact would be seen as 

 respects Switzerland, and a glance at the admirable map of France of 

 De Beaumont and Dufrenoy amply explains my meaning in regard 

 to that highly dislocated portion of the chain which extends south- 

 westwards from the region around Mont Blanc. For Piedmont and 

 Savoy the reader is referred to the good illustrations of Sismonda, 

 not yet, however, brought into one view. 



In treating of the whole chain it must be admitted, that the Swiss 

 and Savoy Alps have been most agitated ; and it is in these most 

 convulsed tracts that we may perhaps best learn what has been the 

 nature of the movements of the strata and the order in which they 

 have followed each other. In parts it is clear, that from the Ju- 

 rassic rocks to the '' flysch " inclusive, there has been a continuous 

 series of submarine deposits (see figs. 3, 4, 12, 14, and the group of 

 sections of Hoher Sentis, Plate VII.). Many deep denudations, in- 

 deed, expose the whole of this series in lofty mountains on either side 

 of deep valleys, each formation in conformable apposition. The most 

 remarkable fact in this collocation is, that all these strata from the 

 eocene downwards, have been thrown into undulations both rapid 

 and gentle, and sometimes have been so contorted as to produce ab- 

 solute inversions. I believe that such flexures were among the earliest 

 of the great physical changes impressed upon these submarine strata, 

 which, at the time when they were so bent, may I conceive have been 

 of no greater solidity and compactness than many of the soft deposits 

 which now constitute the crust of the earth in Russia* and other 

 countries, where the processes of induration and crystallization have 

 not been carried out. It seems to me, that however we may attempt 

 to detect the power which produced these folds and contortions, we 

 must admit that all the strata so folded together, had been accumu- 

 lated the one over the other under the sea (often continuously), and 

 could only have been slightly solidified before the operation com- 

 menced by which they all partook of common and conformable move- 

 ments of undulation. 



In no part of the Alps, which I have examined, are the curvatures 



* See Russia and the Ural Mountains, vol. i. passim. 



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