40 PROCEEDINaS OF THE GEOLOGICAL SOCIETY. 



older formations may "be, besides that of joresent apparent conformable 

 succession. The anthor attributes all this contortion to the revolu- 

 tion which gave to the limestone-range its present aspect : much 

 of the Yorarlberg was dry land duiing the Flysch period, and after 

 it the whole mountain-region became dry land. The greatest revolu- 

 tion here occurred after the Molasse, — in proof of which M. Escher 

 adduces, first, the great local contortion of the Molasse ; secondly, 

 the intimate connexion of the Molasse and the limestone mountain, 

 so that the present position of both must be the result of the same 

 effort ; and, thirdly, the fresh and weU-defined relation of the moun- 

 tain-contours to the position of the strata, and the correspondence of 

 these features throughout the whole mountain-section. In short, 

 the abruptness and comparatively good preservation of the Alps 

 seems to indicate their youthfulness ! The independence of the outer 

 mountain-friDge, and of the indented boundary of the central masses, 

 suggests how much greater the force must have been which pro- 

 duced the former. Yet the general similarity in the features of dis- 

 turbance proves both to have been acts of the same long process. 



M. Eozet*, from the slight disturbance of the Molasse in the 

 French Alps, considers that the greatest dislocations of the mountains 

 occurred between the Eocene and Miocene periods. 



In the Eastern Alps we find M. Stur f adopting the usual theories. 

 After the Eocene period a great disturbing force broke up the 

 hitherto little-troubled regular succession of formations, jDroducing 

 the fan-structure and the transverse valleys. After a succession of 

 subsidences for the deposition of the jSTeogene strata, there came the 

 last great fissuring and upheaval, the floods occasioned by which 

 produced the diluvium. 



M. Bninner:|: makes a great effort at a rational imxprovement 

 upon the usual mode of explanation, but seems to involve the 

 question in more difficulties and apparent contradictions. Thur- 

 mann's explanation of the flexures of the Jura mountains, by the 

 Al]Dine upheaval, is rejected on account of the intervening area of 

 undistui^bed Molasse ; and similarly the folds of the Stockhom 

 cannot be due to Alpine upheaval, on account of the Elysch of 

 the Sim men thai. This observer rejects the mode of action called 

 plutonic, and localizes the cause, finding adequate force in the 

 expansion due to crystallization. Still the lateral displacement is 

 connected with the upheaval. The actual Molasse boundary is 

 not considered a shore of that period ; the rocks sre said to be broken 

 sharply at the junction. The author accounts for what he calls the 

 abnormal projection of the boundary at the Stockhorn, and the 

 absence of Xagelfluhe, by the greater lateral sliding of the mountain- 

 mass at this spot. Eor the four shocks usually reckoned for the 

 production of the Alps M. Brunner substitutes one long upheaval, 

 commenced after the Lias, and continued uniformly until after the 

 Molasse. 



* Bull. Soc. aeol. Trance, vol. xii. 1854-55, p. 204. 



t Sitzungsberichte der k. Akad. Wien, vol. xvi. 1855, p. 477. 



X Neue Denkschriften, Zurich, toI. xv. 1857. 



