308 S. E. Hoicorth—A Great Post-Glacial Flood. 



merely found in the valley of the Ehine, but over a much wider 

 area independent of the drainage of the country. Again, Professor 

 Kamsay speaks of the Rhine at first occupying the whole valley 

 from the Jura to the Black Forest, without explaining how such 

 a gigantic river could have existed at all in this part of Europe. 

 What area did it drain, whence did it derive its supply of water? 

 Unless the whole of the water-shed were entirely different, and on 

 a vastly different scale, it is incredible whence such a volume of 

 water as would be required to fill the whole breadth of the Khine 

 valley between its limiting buttresses of mountain could have been 

 derived ; but there are other and more direct objections against the 

 theory, which have been formulated by Sir Charles Lyell, Mr. Belt, 

 and others. Mr. Belt has brought a number of these objections to 

 a focus, and it will not be inopportime to quote what he says, which 

 is mainly based on Lyell's own inductions. He says, " The Loess 

 rests on previously deposited beds of gravel. At Wurzberg this 

 gravel lies at only a slight elevation above the level of the river, 

 and Dr. Sandberger informed me that it goes down to at least 

 50 feet below it. Here then the valley must have been excavated 

 below its present depth to allow of the deposition of the gravel 

 which preceded that of the Loess. Near Basel the older gravel 

 rests directly against the steep slopes of the rocks bounding the 

 valley, proving again that the latter had been excavated long before 

 the deposition of the Loess commenced. At Mosbach the gravels, 

 containing an older fauna than that of the Loess, though above 

 the level of the river, are yet several hundred feet below the 

 altitude the Loess attains to." The continuity and distribution 

 of the Terraces point the same moral. Formerly it was supposed 

 that the Upper and Lower Terraces differed in contents and in age ; 

 but assuredly Mr. Tylor's most exhaustive researches showed this 

 view to be untenable. He seems to me to have proved that in 

 texture and in contents (shells, bones, and paliBolithic implements) 

 the Terraces belong to precisely the same geological horizon. He 

 has shown, I think, in the case of the Valley of the Somme, that 

 there are not two valley terraces of distinct age, the upper one 

 being older than the lower, but that the deposits are continuous 

 " on gradual slopes from the higher to the lower levels in the 

 valley, except in rare cases or isolated spots, where the continuity 

 is interrupted or prevented by some outstanding piece of the original 

 rock out of which the valley had been originally cut, in which 

 case the gravel wraps round the base of the upstanding knoll of 

 chalk." 



Two of the conclusions which he ura:es, and which I think are 

 irrefragable, are — 



" ] . That the surface of the chalk in the valley of the Somme had 

 assumed its present form prior to the deposition of any of the gravel 

 or Loess now to be seen there, and in this respect corresponds with 

 all other valleys in which Quaternary deposits of this character are 

 met with. 



" 2. That the whole of the Amiens valley gravel is of one formation 



