CHAPTEE XXII. 



EQUILIBRATION. 



§ 170. And now towards what do these changes tend? 

 Will they go on for ever? or will there be an end to them? 

 Can things increase in heterogeneity through all future 

 time? or must there be a degree which the differentiation 

 and integration of Matter and Motion cannot pass? Is it 

 possible for this universal metamorphosis to proceed in the 

 same general course indefinitely? or does it work towards 

 some ultimate state, admitting no further modification of 

 like kind? The last of these alternative conclusions is that 

 to which we are inevitably driven. Whether we watch 

 concrete processes, or whether we consider the question in 

 the abstract, we are alike taught that Evolution has an im- 

 passable limit. 



The re-distributions, of matter that go on around us, are 



ever being brought to conclusions by the dissipation of the 



motions which effect them. The rolling stone parts with 



portions of its momentum to the things it strikes, and finally 



comes to rest; as do also, in like manner, the various things 



it has struck. Descending from the clouds and trickling 



over the Earth's surface till it gathers into brooks and rivers, 



water, still running towards a lower level, is at last arrested 



by the resistance of other water that has reached the lowest 



level. In the lake or sea thus formed, every agitation raised 



by a wind or the immersion of a solid body, propagates itself 



around in waves that diminish as thev widen, and gradually 



496 



