PROPOSED THEORY. 



293 



station at Joinville. It was 8ft. Gin. in length, with a width 

 of 2ft. Sin. and a thickness of 3ft. 4 in. Even when we 

 remember that at the time of its deposition the valley was 

 not excavated to its present depth, we must still feel that a 



Fig. 141. 



fr^ "'^'ffrT:; /r ;/' ' ^^fiBgfe^ 

 O^.Acv,ysLJ^V^^riv*^' AL*4&iM&i 





Section at Joinville. 



body of water with power to move such masses as these must 

 have been very different from any floods now occurring in 

 those valleys, and might fairly deserve the name of a 

 cataclysm. But whence could we obtain so great a quan- 

 tity of water? We have already seen that the gravel of 

 the Oise, though so near, is entirely unlike that of the 

 Somme, while that of the Seine, again, is quite different from 

 that of any of the neighbouring rivers. These rivers, there- 

 fore, cannot have drained a larger area than at present ; the 

 river systems must have been the same as now. Nor would 

 the supposition, after all, account for the phenomena. We 

 should but fall from Scylla into Charybdis. Around the 

 blocks we see no evidence of violent action ; in the section at 

 Joinville, the grey subangular gravel passed under the large 

 block above-mentioned, with scarcely any traces of disturbance. 

 But a flood which could bring down so great a mass would cer- 

 tainly have swept away the comparatively light and moveable 

 gravel below. We cannot, therefore, account for the phe- 

 nomena by aqueous action, because a flood which would 

 deposit the sandstone blocks would remove the underlying 

 gravel, and a flood which would deposit the gravel would 



