5° 



VESTIGES OF THE 



75 per cent., must also be enormous. If all this were 

 disengaged in a gaseous form, the constitution of the 

 atmosphere would undergo a change, of which the first 

 effect would be the extinction of life in all land animals. 

 But a large proportion of it must have at one time been 

 in the atmosphere. The atmosphere would then, of 

 coarse, be incapable of supporting life in land animals. 

 It is important, however, to observe that such an atmo- 

 sphere would not be inconsistent with a luxuriant land 

 vegetation ; for experiment has proved that plants will 

 flourish in air containing one-twelfth of this gas, or i66 

 times more than the present charge of our atmosphere. 

 The results which we observe are perfectly consistent 

 with, and may be said to presuppose, an atmosphere 

 highly charged with this gas, from about the close of the 

 pi'imary non-fossiliferous rocks to the termination of the 

 carboniferous series, for there w^e see vast deposits (coal) 

 containing carbon as a large ingredient, while, at the 

 same time, the leaves of the Stone Booh present no 

 record of the contemporaneous existence of land animals. 



The hypothesis of the connexion of the first limestone 

 beds with the commencement of organic life upon our 

 planet is supported by the fact, that we soon after, in 

 ascending through the series of rocks, find the first dis- 

 tinct remains of the bodies of animated creatures. 



And what w^ere those creatures? It might well be 

 \vith a kind of awe that the uninstructed inquirer would 

 wait for an answer to this question. But Nature is 

 simpler than man's wit would make her, and behold, the 

 interrogation only brings before us the unpretending 

 forms of various zoophytes and polypes, together with a 

 few single and double-valved shell-fish (mollusks), all of 

 them creatures of the sea. It miglit have been expected 

 that vegetables would first make theii- appearance, as 



