CONDITION OF MAX IN FEE-HISTORIC TIMES. 29 



the pendulum of temperature lasting for no less than 

 21.000 years. This explains the fact that, as Morlot 

 showed in 1854, the glacial deposits of Switzerland, 

 and, as we now know, those of Scotland, are not a 

 single uniform layer, but a succession of strata indi- 

 cating very different conditions. I agree also with 

 Croll and Geikie in thinking that these considerations 

 explain the apparent anomaly of the co-existence in the 

 same gravels of arctic and tropical animals ; the former 

 having lived in the cold, while the latter nourished in 

 the* hot, periods. 



It is, I think, now well established that man in- 

 habited Europe during the milder periods of the glacial 

 epoch. Some high authorities indeed consider that we 

 have evidence of his presence in pre-glacial and even in 

 Miocene times, but I confess that I am not satisfied on 

 this point. Even the more recent period carries back 

 the record of man's existence to a distance so great as 

 altogether to change our views of ancient history. 



Nor is it only as regards the antiquity and material 

 condition of man in pre-historic times that great pro- 

 gress has been made. If time permitted I should have 

 been glad to have dwelt on the origin and development 

 of language, of custom, and of law. On all of these 

 the comparison of the various lower races still inhabiting 

 so large a portion of the earth's surface, has thrown 

 much light ; while even in the most cultivated nations 

 we find survivals, curious fancies, and lingering ideas ; 

 the fossil remains as it were of former customs and 

 religions, embedded in our modern civilisation, like the 

 relics of extinct animals in the crust of the earth. 



