568 Scientific Proceedings, Royal Dublin Society. 



scattered through infinite space. For as, by hypothesis, the aggre- 

 gation occupies an infinite time in consummation it is nearly a 

 certainty that each particle encountered after immeasureable time^ 

 and then for the first time endowed with actual gravitational 

 potential energy, would have long expended this energy before 

 another particle was gathered. But the fact that so many fires 

 which we know to be of brief duration are scattered through a 

 region of space, and the fact of a configuration which we believe 

 to be a transitory one, suggest their simultaneous aggregation 

 here and there. And in the nebulous wreaths situated amidst 

 the stars there is evidence that these actually originated where 

 they now are, for in such no relative motion, I believe, has as 

 yet been detected by the spectroscope. All this, too, is in keeping 

 with the nebular hypothesis of Kant and Laplace so long as this 

 does not assume a primitive infinite dispersion of matter, but the 

 gathering of matter from finite distances first into nebulous 

 patches which aggregating with each other have given rise to our 

 system of stars. But if we extend this hypothesis throughout an 

 infinite past by the supposition of aggregation of infinitely remote 

 particles we replace the simultaneous approach needed to account 

 for the simultaneous phenomena visible in the heavens, by a 

 succession of aggregative events, by hypothesis at intervals of 

 nearly infinite duration, when the events of the universe had 

 consisted of fitful gleams lighted after eternities of time and 

 extinguished for yet other eternities. 



Finally, if we seek to replace the eternal instability involved 

 in Kant's hypothesis when extended over an infinite past, by any 

 hypothesis of material stability, we at once find ourselves in the 

 difficulty that from the known properties of matter such stability 

 must have been permanent if ever existent, which is contrary to 

 fact. Thus the kinetic inertia expressed in Newton's first law 

 of motion might well be supposed to secure equilibrium with 

 material attraction, but if primevally diffused matter had ever 

 thus been held in equilibrium it must have remained so, or it was 

 maintained so imperfectly, which brings us back to endless 

 evolution. Again, a primitive infinite and stable diffusion had 

 either remained so, or supposing chance to have led to its dissolu- 

 tion, the subsequent gradual evolution had been at variance with 

 the simultaneity of our universe. 



