312 LAPSE OF TIME. 



Somme was but beginning its great task ? No one can pro- 

 perly appreciate the time required who has not stood on the 

 heights of Liercourt, 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 change which has taken place, and the enormous time 

 which must have elapsed since the first appearance of man 

 in Western Europe. 



