332 THE SUPPOSED PERMANENCE [CHAP. XV. 



for the permanence of oceans and continents has by no 

 means been made out, and that when the arguments which 

 have been urged in its favour are carefully examined, none 

 of them are found to be very convincing, and certainly 

 none are unanswerable. A review of the great geographical 

 transformations which the western part of Europe has 

 undergone leads to the conclusion that the present conti- 

 nent, meaning by this any compact mass of land occupying 

 the position of modern Europe, does not date back farther 

 than the beginning of Eocene time, and possibly not beyond 

 Oligocene time. The range of the Eocene Nummulitic 

 limestones proves that the whole of southern Europe, to- 

 gether with large parts of Asia Minor and of Northern 

 Africa, were at that time the site of a fairly deep sea, but 

 it is true that there was a considerable amount of land over 

 the northern part of the European region, and it may 

 therefore be argued that the continent existed, though its 

 limits were then very much circumscribed. 



When, however, we go back to the Cretaceous period, it 

 must be admitted that the sea in which the Chalk was de- 

 posited had an extent (see p. 328) that fairly entitles it to 

 be called an ocean, and further, that very little land could 

 then have existed over the site of Europe, such portions of 

 northern Europe as were then land belonging in fact to a 

 more northern continent which could not by any reasonable 

 method of nomenclature be identified with modern Europe. 

 We need not, therefore, go farther afield or farther back in 

 time to find evidence for the interchange of an ocean and a 

 continent. 



It may readily be admitted that the deeper parts of the 

 existent oceans are of great antiquity, and it is probably 

 not too much to say that they have never been land since 

 an early date in Mesozoic time, but this admission is very 

 different from the assertion that they date their existence 

 from the very beginning of geological history. Such geo- 



