42 GEOLOGY AND HISTORY 



whose remains are accessible to us, though rude 

 themselves, may have belonged to more advanced 

 races. 



The bones, implements and weapons, and debris 

 of the feasts of these primitive peoples are to be found 

 principally in caves of residence or of sepulture, 1 and 

 in the alluvia deposited by rivers, and in a few cases 

 in rock fissures or marine gravels, into which remains 

 were drifted, or in which they were deposited by 

 water. Here, again, we have another limitation, for it 

 is possible that large populations may have lived on 

 plains or in forests in perishable structures, and, like 

 some modern savages, may have disposed of their 

 dead in such a way that their bones could not have 

 been preserved. In such cases we can hope to obtain, 

 and then very rarely, only stone implements and other 

 imperishable relics. 



Notwithstanding these limitations, however, it is 

 wonderful that so much has been recovered from the 

 ground by the diligence of collectors, and that the 

 material thus obtained has proved so fertile in in- 

 formation respecting our long-perished ancestors. 



1 Caverns, in relation to this subject, may be divided into those of 

 residence, in which early men have lived and have left therein the 

 debris of their food, the ashes and cinders of their fires, and imple- 

 ments, &c. ; those of sepulture, in which the bodies of the dead have 

 been deposited ; and those of inundation, into which the bodies of 

 anim'als or men have been drifted by floods. The same cave may, 

 however, exhibit these different conditions in the deposits on its succes- 

 sive floors. Thus men may have inhabited a cave for a time ; it may 

 next have been invaded by river floods depositing mud, and it may 

 subsequently have been used for burial. 



