112 AUTUMNS ON THE SPEY. 



palaeozoic non-fossiliferous rocks, but the Silurian 

 deposits with their corals, molluscs and Crustacea. 

 All subsequent periods unrepresented, though 

 each had its fauna and flora and lasted for millions 

 of years ! Palaeozoic, Mesozoic, Cainozoic : all 

 passed away without leaving behind a trace of 

 their existence. The coal-seams and compact 

 limestones of the carboniferous age ; the col- 

 oured sandstones and magnesian limestones of 

 Permia ; the salt deposits of the Trias ; the rep- 

 tilian bearing beds of the oolite ; the marine 

 fauna of the chalk ; the more modern strata of 

 the tertiaries and post-tertiaries ! Can we wonder 

 if the human mind is bewildered in endeavouring 

 to realize the duration of these accumulated ages ? 

 Driven to the vei*y extremity of the abyss of 

 thought, it has sometimes seemed to me that the 

 philosophical sentiment of the Roman poet might 

 often apply to the modern student of the world's 

 history, 



" Quiesivit ccelo lucem, ingemuitque repertft." 



Yet it is a matter of strict scientific demonstration 

 that the time which has elapsed since the first 

 appearance of man on this earth up to the present 

 moment is absolutely insignificant when compared 

 with the interval between that event and the period 



