48 IN STARR Y REALMS. 



pose that in the depths of space it should happen that 

 two globes, each as large as our earth and each having 

 a velocity of eighteen miles a second, rushed into direct 

 collision ; it can be shown that the energy which would 

 be transformed by the shock would be adequate, when 

 converted into heat, to raise the two bodies not merely 

 to incandescence but even to transmute them into a 

 gaseous nebula. Here then we have a possible explana- 

 tion as to how the nebula from which our sun has been 

 developed was originally formed. It may have been 

 produced, and most likely was produced, by the collision 

 between two other bodies. In the same way it may yet 

 conceivably happen that after the sun shall have grown 

 condensed and cold, and is journeying on with enormous 

 velocity through space, it may again come into collision 

 with some other body, and the transformation of the 

 energy from motion into heat may again generate another 

 nebula, and set in progress yet another evolution like that 

 through which we are at present passing. 



