382 RECAPITULATION. 



of time indicated, who has not stood on the heights of Lier- 

 court, Picquigny, or on one of the other points overlooking 

 the valley ; nor, I am sure, could any geologist return from 

 such a visit without an overpowering sense of the changes 

 which have taken place, and the length of time which must 

 have elapsed since the first appearance of man in Western 

 Europe. 



