ANTIQUITY OF MAN. 215 



exclude from the true Palaeolithic period, as defined 

 above, all the known cases, except those of the river- 

 gravels and shore-gravels of the cretaceous districts of 

 western Europe, because all the other repositories, 

 even those containing bones of the mammoth, show 

 implements of more advanced construction. It is 

 further obvious that with regard to these gravels the 

 exceptional conditions above referred to come into full 

 force. First, the implements occur principally in 

 those cretaceous regions in which flints well suited for 

 chipped implements abound. Hence it is likely that 

 rude tribes migrating from place to place might not 

 care to take with them ordinary implements, but 

 might make a new supply wherever they happened to 

 be, and then abandon them. A very few such imple- 

 ments as those found at Amiens would be burdensome 

 to a savage in his journey, and when he knew that at 

 any place in the district he could procure flints and 

 make a new supply in an hour or two, he would not 

 fatigue himself with their weight. He would be more 

 likely to carry a light hammer of stone or antler or 

 tooth, with which he could chip flints as he required 

 them. Secondly, independent of this, a region so 

 abundantly supplied with flint might be visited by 

 remote tribes who might spend weeks in the chipping 

 of flints, and then leave the locality, taking with them 

 those which were most suitable for use, or for further 

 working into finer weapons. Resident tribes also, if 

 sufficiently powerful to prevent others from visiting 

 the gravel-beds, might manufacture or roughly block 



