PT. i. Astronomy and Geology compared. 55 



faintest traces of lichen upon the rock to the actual 

 state of the World there is a continuity which 

 includes all the links in one vast whole. We are, 

 however, constantly reminded that this is a very new 

 science : it indefinitely extends the area of our con- 

 ception, but it rarely traces bounds or limits. If we 

 take, for instance, Sir Charles Lyell's able work on the 

 ' Antiquity of Man,' he has succeeded in unsettling 

 all our previous ideas, but he has not substituted 

 any others of a fixed character; he does not the 

 least inform us whether Man has existed 10,000 or 

 100,000 years upon the face of the Globe. Perhaps 

 this imperfection will be owing to the recent birth of 

 this branch of knowledge, and the labours of future 

 Geologists may give us additional clues through the 

 labyrinth of the past. 



In pursuing that comparison between Astronomy 

 and Geology which it has been the object of this 

 treatise to institute, we must conclude that the 

 advantage in point of certainty largely preponderates 

 in favour of Astronomy. The retrospect to which 

 Geology invites us is indeed a noble one in suggest- 

 ing the grandest speculations upon the birth and 

 youth of the Creation. But Astronomy, still grander 

 in its proportions, inasmuch as it deals not only with 





