COSMIC PHILOSOPHY 



as fast as it came. Or, as Mayer has calculated, 

 the amount of heat lost every minute by the 

 sun would suffice to raise the temperature of 

 thirteen billion cubic miles of water one degree 

 Centigrade. Although this prodigious loss is 

 perhaps partly compensated by heat due to the 

 arrested motion of meteors falling upon the 

 sun's surface, yet it is by no means probable 

 that it is in this way compensated to any note- 

 worthy extent. It is in every way indisputa- 

 ble that from time immemorial sun, moon, and 

 earth, as well as the other members of our sys- 

 tem, have been parting with their internal mo- 

 tion, in the shape of heat radiated into sur- 

 rounding space. 



Thus in the history of our planetary system 

 we may already begin to witness that dissipation 

 of motion which has been shown to be one of 

 the prime features of the process of Evolution, 

 wherever exemplified. But, as we have also 

 seen, the dissipation of motion is always and 

 necessarily accompanied by the concentration 

 of matter. It is not simply that, with two or 

 three apparent exceptions, which have no bear- 

 ing upon the present argument, all cooling 

 bodies diminish in size and increase in density ; 

 but it is also that all contracting bodies gener- 

 ate heat, the loss of which, by radiation, allows 

 the process of contraction to continue. In any 

 contracting mass the particles which tend to- 

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