ANTIQUITY OP MAN. 247 



animals the greater part of which still survive, and 

 his introduction at the close of that great and as yet 

 very mysterious revolution of the earth which we call 

 the Glacial period, accords, as I have elsewhere en- 

 deavoured to show,* with the analogy of geological 

 science, in the information which it gives as to the 

 first appearance of other types of organic being in the 

 several stages of development of our earth. 



The reader may perhaps ask, If these conclusions 

 are so plain, why has there appeared to be so general 

 an admission of the great antiquity of man on the 

 part of geologists and archaeologists ? The reasons of 

 this are not difficult to discover. They are such as 

 the following: the great intricacy and difficulty of 

 the geological questions connected with the close of 

 the Glacial age and the beginning of the Modern 

 period ; the difficulty of verifying alleged facts as to- 

 the occurrence of remains in superficial deposits, and 

 of ascertaining the age of these deposits and their free- 

 dom from modern admixtures ; the small number of 

 geologists and archaeologists qualified by knowledge 

 and experience to deal with questions of this kind; 

 the enthusiasm with which novel and startling dis- 

 coveries, and especially those appearing to contradict 

 old and received opinions, are welcomed at present ; 

 the exigencies of the new philosophy of evolution, one 



* See the more full discussion of this subject in the "Story 

 of the Earth," and the " Origin of the World," and in my 

 Address as President of the Geological Section of the Ameri- 

 can Association, in 1876. 



