AT THE EARTH'S SURFACE. 421 



The only reason, at least, that would lead to hesitation in 

 admitting this last inference, is a hypothetical one, — that it is 

 inconsistent with that perfect arrangement; which we are dis- 

 posed to believe exists among all the heavenly bodies, whence 

 the stability of the entire system is maintained, and whence, 

 therefore, in relation to any communication of caloric among 

 them, the quantity radiated by each will, on the whole, be 

 equal to what it receives. This, whether we restrict the view 

 to the different parts of our solar system, or extend it even to 

 the universe, is no doubt the conclusion which the imagina- 

 tion is naturally disposed to embrace, though it may not be 

 supported on any decisive evidence, or may even be in some 

 measure apparently in opposition to the fact. But to suppose 

 that this planet discharges more caloric than it receives, would 

 be not only in opposition to evidence, but in opposition to 

 the very principle which alone leads to the admission 

 that the quantity discharged may be equal to the quantity re- 

 ceived. 



Concluding, then, as it appears to me, may be strictly infer- 

 red from the preceding reasoning, that our earth does not dis- 

 charge caloric from its surface into the regions of space, or at 

 least does not discharge more than it receives from the other 

 heavenly bodies, if it discharge even this, the argument recurs, 

 I believe, in its original form, as sufficiently established, That 

 if an interior heat exist, it must be diffused through the sub- 

 stance of the earth, and an equilibrium of temperature be at 

 length established, incompatible with those operations ascri- 

 bed to its action in the Huttonian Theory. 



But farther, though the heat were not retained, — though it 

 were granted that it is propagated into the regions of space; 

 this does not render the argument I have urged less con- 

 clusive. The strength of that argument lies in the circumstance, 

 of the diffusion of heat from the interior, not in the accu- 



Vol. VIL P. II. 3 H mulation 



