CHAP. VII 



THE GLACIAL EPOCH 



111 



Jura at G have come from the eastern shoulder of Mont 

 Blanc in the dkect line 7^ B F G. Here the glacier would 

 naturall}^ preserve its greatest thickness, while as it spread 

 out eastward and Avestward it would become thinner. We 

 accordingly find that the travelled blocks on either side of 



Blanc 



MAP SHOWING THE fOX-RSE OP THE ANCIENT GLACIER OP THE RHONE AND THE 

 DISTRIBUTION OF ERRATIC BLOCKS ON THE JURA. 



the central point become lower and lower, till near Soleure 

 and Geneva they are not more than 500 feet above the 

 valley. The evidence is altogether so conclusive that, after 

 personal examination of the district in company with 

 eminent Swiss geologists. Sir Charles Lyell gave up the 



