Structure of the Eastern Alps. 375 



Below the coal there are irregular bands of argillaceous marl, with thin 

 laminse of imperfect lignite, traversed by numerous small veins of carbonate 

 of lime ; and pyrites is so abundant in these thin beds, that much vitriol has 

 been extracted from them. 



Finally, the whole deposit is separated from the secondary system, on 

 which it rests unconformably, by a thin, irregular band of conglomerate, 

 almost entirely made up of fragments of Alpine limestone, in which are seen 

 the organic remains peculiar to it, such as Terebratulae, Belemnites, &c. 



The thickness of the beds in the previous section is estimated in Vienna 

 feet, and in the direction of the horizontal drift line. As, however, the several 

 groups of strata along this line are on the average inclined at about 36°, it is 

 obvious that their true thickness, estimated in the direction of a line perpen- 

 dicular to their planes, is only a little more than half that which is indicated 

 by the numbers affixed to them. 



The preceding details have, we hope, conveyed a correct, general notion 

 of the relations of the Hiiring lignites ; and we may remark by way of 

 conclusion, 1st, That the overlying groups on the left bank of the Inn are 

 brought successively into contact with the older Alpine limestone, the red 

 marl and conglomerate, and the dolomitic beds associated with them — that 

 on the other side of the basin, the same groups come into contact only with 

 the younger divisions of the Alpine limestone — and that this collocation 

 arises out of their unconformable position among the ancient formations 

 of the chain. 2dly, That during the progress of the deposit, the sea pene- 

 trated far up the valley of the Inn — and that, consequently, the chain 

 must have undergone a great movement of elevation since the completion of 

 the overlying groups. Srdly, Notwithstanding this last movement of elevation, 

 and the subsequent degradations of the chain — that the valley of the Inn 

 existed somewhat in its present form before the commencement of the deposit 

 — and, consequently, that the great disturbing forces which dislocated and 

 broke up the older parts of the neighbouring chain had come into action at 

 a time anterior to the existence of the whole overlying series. 



2. Sections on the Banks of the Lech; various Deposits of Lignite, Sgc. 



None of the previous sections, excepting that of Bregenz *, conveys any 

 adequate notion of the enormous thickness of the tertiary series between 

 the north flank of the Alps and the plains of the Danube. Our attention was 

 so much given to the dislocated groups on the skirts of the secondary system, 

 that we had no time for any detailed examination of the strata descending 



* Plate XXXVI. fig. 3. 



