THE HUMAN SPECIES. 135 



in any other part of England, appear to have occurred, and 

 phenomena on shore are equally surprising. A part of the 

 bed of the Severn is stated to have risen, in 1773, to the height 

 of thirty feet, the back water immediately forming a lake, 

 which was drained by cutting a new channel. According to 

 Camden, and Bishop Hakewell's Apology, at the time of the 

 Norman Conquest, part of Pembroke formed a promontory, 

 extending towards Ireland; but the space was already sunken 

 beneath deep sands, in the time of Henry II., when a violent 

 storm so far uncovered the original surface, that many stumps 

 of trees appeared fixed in the earth, "and the strokes of the 

 axe upon them quite fresh." 



In the Welsh Triads, Orkney, the Isle of Man, and the Isle 

 of Wight, are styled the three adjacent islands of Britain ; and 

 they proceed to mention the subsequent separation of Anglesea 

 from the main land. Nennius similarly alludes to the three 

 adjacent islands; yet, since that period, Orkney became divided 

 into several parts ; and it is evident that other portions of 

 Wales and Western Scotland likewise became insulated. So 

 many important changes, particularly in the British Channel, 

 imply the agency of forces which were not in activity at very 

 remote periods; for, had they been of primeval date, their 

 operation would have effected the whole of the changes they 

 necessitated long before the dates here mentioned. 



SOUTHERN EUROPE. 



Returning to the west coast of France, we find the important 

 invasion of the sea, which in the eighth century destroyed a 

 great space of poor and forest land, separating Mont St. 

 Michael from the main shore;* and in the Bay of Biscay, 



♦There is an earlier great event of this kind recorded in history, in the 

 reign of Gallienus, when one or two Romano-Celtic cities, in Armorica 

 or Bretagne, were destroyed. That in the reign of Charlemagne was 

 equally destructive on the coasts of France and in the Baltic. 



