414 Professor Sedgwick and Mr. Murchison on the 



same level. But in the south-western parts of Bavaria, where they form the 

 water-shed between the Danube and the Rhine, they are greatly elevated 

 above the corresponding groups further towards the east, and are even at 

 higher levels than the old beds of the Inn and the Salza, many leagues within 

 the barriers of Alpine limestone. 



It follows unequivocally from the preceding statements, that *the chain of 

 the Eastern Alps has been exposed to many shocks and independent move- 

 ments of elevation. Some of the most violent of these shocks were followed 

 by the production of conglomerates. Thus we find conglomerates, where 

 they might have been expected, underlying the horizontal deposits of Gosau, 

 and overlying still newer deposits set on e(\^Q by the last movement of the 

 chain. 



As a general rule, applicable to most parts of the Eastern Alps which we 

 have examined, conglomerates are not only much more abundant, but also of 

 coarser texture in the newer than in the older formations. This again is a 

 result which might have been anticipated. The oldest strata were formed 

 under the sea, perhaps before any Alpine chain existed. The deposits of the 

 middle age were formed on the sides of mountains much less elevated than 

 they are now, and therefore supplying fewer materials for mechanical degra- 

 dation. But the tertiary groups had their origin in a sea which washed the 

 base of the Alpine chain already greatly elevated, and supplying, not merely 

 by debacles and other extraordinary movements, but by the action of the 

 waves beating on its sides, and by the erosion of torrents wearing their way 

 through its transverse valleys, abundant materials for the masses of conglome- 

 rate such as we have described. 



The chain of the Eastern Alps has then been exposed, not only to the 

 shocks of elevation above indicated, but, undoubtedly, to many others, of 

 which we have not yet seen the physical trace. Long periods of ages elapsed 

 between the successive greater movements ; and during those periods moun- 

 tain masses of conglomerate were formed, time after time, at the loss of the 

 pre-existing rocks. In such facts as these we have a ready answer to any 

 difficulties suggested by the appearance of the overlying groups (at Gosau, 

 Zlam, &c.) among the high valleys of Alpine limestone. The powers of de- 

 gradation have been at work ever since the chain first rose above the waters : 

 and in bringing together, in imagination, the disjointed fragments of an 

 ancient deposit, we have no right to look among" them for any certain traces 

 of the shores and bays of that sea which beat against the sides of the Alps at 

 the time of their formation ; nor are the powers of degradation now sus- 



