The sun is represented as an incan- 

 descent mass, inconceivably hot, with a 

 temperature rated at millions of degrees ; 

 yet heat diminishes in the direction of 

 the sun, and at a short distance from 

 the earth the temperature becomes in- 

 conceivably cold. Thus no particle of 

 heat reaches the earth, from that body, as 

 heat. 



In like manner sun light, which is 

 subject to the same creative cause, and 

 the same method of transmission as 

 sun-heat, rapidly diminishes in the 

 direction of the sun ; so rapidly that 

 the sun, at the elevation of a few miles, 

 looses its brilliancy, and may be viewed 

 with undazed eye. 



The sun is therefore presumably cool 

 and dark, not differing from the earth 

 -in its physical conditions and in its ha- 

 bitability. 



The vastly important inference there- 

 fore. an inference that must lie at the 

 bottom of all true physical philosophy, 

 is, that there is some great primordial 

 principle acting through the sun, and 

 which is so fitted to operate upon our 

 atmosphere as that it causes all neces- 

 sary forms of activity in air and earth. 



These varied forms of activity, 

 though we call them "the physical for- 

 ces" as if they were really distinct and 

 independent, and not but correlated 

 forms, embrace certain peculiar activ- 

 ities which we term cold, as truly as oth- 

 ers which we call light, heat, electricity, 

 etc. 



It is the constant recognition every- 

 where, of the great primordial principle 

 operating differently according as it is 

 differently conditioned, that must set us 

 into the right understanding of all phys- 



