DARWINISM AND EVOLUTION 179 



the cosmos as an almost infinite collection of material 

 atoms, animated by an almost infinite sum- total of 

 energy, potential or kinetic. 



In the very beginning, so far as the mental vision 

 of the astronomer can dimly pierce with hypothetical 

 glance the abyss of ages, the matter which now com- 

 poses the material universe seems to have existed in a 

 highly diffuse and nebulous condition. The gravitative 

 force, however, with which every atom of the whole 

 vast mass was primarily endowed, caused it gradu- 

 ally to aggregate around certain fixed and definite 

 centres, which became in time the rallying-points or 

 nuclei of future suns. The primitive potential energy 

 of separation in the atoms of the mass was changed 

 into actual energy of motion as they drew closer and 

 closer together about the common centre, and into 

 molecular energy or heat as they clashed with one 

 another in bodily impact around the hardening cora. 

 Thus arose stars and suns, composed of fiery atomic 

 clouds in a constant state of progressive concentration, 

 ever gathering-in the hem of their outer robes on the 

 surface of the solid globe within, and ever radiating 

 off their store of associated energy to the impalpable 

 and hypothetical surrounding ether. This, in neces- 

 sarily brief and shadowy abstract, is the nebular theory 

 of Kant and Laplace, as amended and supplemented by 

 the modern doctrine of the correlation and conservation 

 of energies. 



Applied to the solar system, of which our own 

 planet forms a component member, the evolutionary 

 doctrine (in its elder shape) teaches us to envisage that 

 minor group as the final result of a single great diffuse 



