THE BAY OF BISCAY. 149 



Black Mountain, and the Cevennes formed a sort of 

 continent, which extended as far as the Ardennes and 

 the Yosges; Brittany, a portion of Normandy, Maine, 

 and La Vendee were prolonged into a sort of irregular 

 isthmus, and were connected by Poitou with this 

 central plateau, while Flanders, Picardy, Cham- 

 pagne, the Paris basin, Upper Normandy, Touraine, 

 the south of France, and the north of Spain were 

 all one vast sea, in the midst of which rose a fe\v 

 scattered islands. At tlje bottom of this sea were 

 deposited the last strata of the secondary or creta- 

 ceous formations, which by their thickness and 

 variety attest the long period during which this 

 condition of things must have existed. 



This state of repose was disturbed for the first 

 time by the thirteenth upheaval, namely, that of 

 Mont Viso, which gave origin to the French Alps. 

 Then, after another period of tranquillity, came the 

 fourteenth cataclysm, which was one of the most 

 considerable of which we have any traces on the 

 earth's surface. It extended from the western extre- 

 mity of Europe as far as North America, through 

 the whole of Asia ; and it is especially to this up- 

 heaval that the Pyrenees owe their present eleva- 

 tion.* The eruption of the primary rocks which 



regards these numbers as provisional, and as representing only the 

 present condition of science. No one could be less disposed than 

 M. Elie de Beaumont to assign impassable limits to the progress of 

 knowledge, and on this account he has always designated every 

 recognised upheaval by a name, borrowed either from the principal 

 chains which have resulted from it, or from the districts in which it 

 has occurred. 



* The present form of mountain chains is r.ot owing to a single 

 L 3 



