20 



capable of improvement) those which remain unchanged, do so be- 

 cause they are not exposed to the elements of change. 



There is little doubt that man has been upon the earth long 

 enough to have witnessed many physical changes, and even con- 

 siderable modifications in the climate of Europe. We can the more 

 readily accept this, because from the brief portion of the record of 

 our race embraced in the historic period, we know that many changes 

 in physical conditions have come to pass, and some, indeed, are even 

 now taking place around us. . • 



The duration of the Pre-historic period, as compared with the 

 historic, may best be conceived when it is borne in mind that very 

 old countries like India, whose history goes back further into the 

 past than any other, have still a lost history apparently far longer 

 than that handed down to us, evidenced by Megalithic and other 

 monuments of unknown antiquity ; and again, beyond that, Prof. 

 Blanford ; Messrs. King, Foote, Wynne, and other of the Geological 

 Surveyors, have obtained evidence of a still earlier and barbarous 

 race, whose only relics are their stone-implements, fashioned of 

 the Neolithic and Palaeolithic types, like those of the aborigines of 

 Gaul and Britain. 



How many thousands of years must have been occupied in the 

 gradual distribution of these earliest representatives of our race, 

 whose implements have been found in almost every portion of the 

 globe (formed in the same simple yet persistent types), can only be 

 realized by the geologist who has learnt that many prior races of 

 beings lived and spread out over the whole globe, and have been as 

 gradually exterminated and re-placed with other races, who have 

 followed in successive eons, differing in form, yet modelled on types 

 analogous to those now existing. 



