THE LAPSE OF TIME. 113 



the rifles and gunpowder of modern civilization? Let 

 us imagine that within the specified time all that has 

 been mentioned could have happened, and that some of 

 the animals, such as the woolly rhinoceros, had time to 

 assume the characters of northern species, or that the 

 climate had time for vast changes and alterations, or 

 that the winds perhaps in those days blew hot and cold 

 with the same breath so as to suit arctic and tropical 

 species indifferently ; we must imagine further that 

 within the same limits the three floors of stalagmite 

 could have been formed in succession, and two of them 

 successively broken up. They must have been formed, 

 not during the whole of the period, but only during 

 that part of it which followed the introduction into 

 Britain of wild beasts, and of men who used flint 

 weapons ; for one unmistakeable weapon of human 

 manufacture, and innumerable bones of the great old 

 cave bear have been found within the rock-like breccia 

 of stone and stalagmite and cave-earth, some feet be- 

 low both the floors of more recent formation 1 . The 

 longer the period, therefore, we allow for the migra- 

 tion from the East and the dying out of civilized 

 life, the shorter is the period left for the stalagmitic 

 formation. Yet probably the whole twenty-three cen- 

 turies would not suffice for the formation of one of 

 the floors ; how much less could a fraction of the 

 period suffice to form all three, and to supply 

 the intervals during which, through some change of 



1 'Eeport of British Association, 1869,' p. 201. 



I 



