432 TROPICAL NATURE 



advance, man's intellectual and moral development reached 

 almost its highest level in a very remote past. The lower, 

 the more animal, but often the more energetic types have, 

 however, always been far the more numerous ; hence such 

 established societies as have here and there arisen under the 

 guidance of higher minds have always been liable to be swept 

 away by the incursions of barbarians. Thus in almost every 

 part of the globe there may have been a long succession of 

 partial civilisations, each in turn succeeded by a period of 

 barbarism ; and this view seems supported by the occurrence 

 of degraded types of skull along with such " as might have 

 belonged to a philosopher," at a time when the mammoth and 

 the reindeer inhabited southern France. 



Nor need we fear that there is not time enough for the 

 rise and decay of so many successive civilisations as this view 

 would imply, for the opinion is now gaining ground among 

 geologists that palaeolithic man was really preglacial, and that 

 the great gap (marked alike by a change of physical condi- 

 tions and of animal life) which in Europe always separates 

 him from his neolithic successor, was caused by the coming 

 on and passing away of the great ice age. 



If the views now advanced are correct, many, perhaps 

 most, of our existing savages are the successors of higher 

 races ; and their arts, often showing a wonderful similarity in 

 distant continents, may have been derived from a common 

 source among more civilised peoples. 



