10 NATURE STUDIES. 



of years belonging to the lifetime of a planet, the far 

 longer intervals measuring the duration of solar sys- 

 tems, and finally the eternities in which these periods 

 of time, vast though they seem, are utterly lost. But 

 with this widening of men's conceptions as to space 

 and time, should have come also a widening of their 

 ideas respecting the operation of law. Within the 

 petty domains of space which they had surveyed, the 

 growth of a plant or an animal seemed naturally to 

 belong to the domain of development; but wider and 

 grander processes of evolution seemed as far outside 

 men's thoughts as the infinite star depths in which 

 modern science believes, or the vast periods of time 

 during which modern science sees that planets and 

 solar systems have existed. Newton taught men how 

 wide in space is the domain of law, and rightly under- 

 stood, what Newton taught should have shown men 

 how long also in time last processes of development 

 according to fixed law. Yet precisely as men were 

 far readier to accept the doctrine of infinite (or practi- 

 cally infinite) space, than that of inconceivably vast 

 periods of time, so also were they far readier to be- 

 lieve in a law like that of universal gravitation, opera- 

 ting throughout regions of space practically without 

 limit, than to perceive (what this in fact implied) that 

 in time, as in space, the domain of law must be to our 

 conceptions limitless. 



It came, therefore, as a shock even to many of the 

 more thoughtful among us, when Darwin propounded 

 a law of Nature, less grand than Newton's great law, 



