of Animals and Vegetables, as bearing on Palaeontology. 93 



carried down once more into the interior. This is however 

 rather a groundless supposition, there being no apparent mode 

 in which such process could be carried on, seeing that the sur- 

 face of the earth is already oxidized, and, as far as we can judge, 

 has always been so. 



Assuming then that the proposed theory, supported as it is 

 by the fact that the constituents of the atmosphere are not in 

 atomic proportions, and borne out likewise by the foregoing ar- 

 guments, is correct, let us mark the inferences that may be 

 drawn respecting the effects produced upon the organic crea- 

 tion. 



Superior orders of beings are strongly distinguished from 

 inferior ones by the warmth of their blood. A low organiza- 

 tion is uniformly accompanied by a low temperature, and in 

 ascending the scale of creation we find that, setting aside par- 

 tial irregularities, one of the most notable circumstances is the 

 increase of heat. It has been further shown, by modern dis- 

 coveries, that such augmentation of temperature is the direct 

 result of a greater consumption of oxygen; and it would ap- 

 pear that a quick combustion of carbonaceous matter through 

 the medium of the lungs was the one essential condition to 

 the maintenance of that high degree of vitality and nervous 

 energy without which exalted psychical or physical endowments 

 cannot exist. 



Coupling this circumstance with the theory of a continual 

 increase in the amount of atmospherical oxygen, we are natu- 

 rally led to the conclusion that there must of necessity have 

 been a gradual change in the character of the animate crea- 

 tion. If a rapid oxidation of the blood is accompanied by a 

 higher heat and a more perfect mental and bodily develop- 

 ment, and if in consequence of an alteration in the composi- 

 tion of the air greater facilities for such oxidation are afforded, 

 it may be reasonably inferred that there has been a corre- 

 sponding advancement in the temperature and organization of 

 the world's inhabitants. 



Now this deduction of abstract reasoning we know to be in 

 exact accordance with geological observations. An inspection 

 of the records of creation demonstrates that such change has 

 taken place, and although remains have from time to time been 

 found which prove that beings of an advanced development 

 existed at an earlier period than was previously supposed, still 

 the broad fact is not by any means invalidated. A retrospec- 

 tive view of the various phases of animal life, tracing it through 

 the extinct orders of mammalia, saurians, fishes, Crustacea, 

 radiata, zoophytes, &c, shows distinctly that whatever may 

 have been the oscillations and irregularities produced by inci- 



