THE PATH OF EVOLUTION 



words, Xenophanes accepts the geometrical idea of 

 matter and of space. A figure that is continuous and 

 that can be infinitely divided only by destroying it. 



Leucippe, Epicurus and his disciple, Lucretius, on 

 the contrary, assert the numerical idea that matter 

 is discontinuous ; we pass from one number to the 

 next, Per saltum ; the numbers being individuals, 

 and building up the sum or body by their aggrega- 

 tion, which body can be again divided into its original 

 numerals, or individual factors, the atoms. * 



Modern science is still somewhat in doubt between 

 these conflicting views. The laws under which the 

 transmission of light and heat from the sun to the 

 earth and other planets, and the transference of heat 

 on earth from one body to another by radiation, are 

 fully established. They are demonstrated facts. Their 

 phenomena necessitate the assumption that there is 

 something that exists throughout infinite space be- 

 tween us and the far distant star that even the latest 

 and most powerful telescopes fail to reveal : so far 

 off that its light even then is not directly perceptible 

 to human vision, but proves its presence through the 

 slow action of the telescopic camera upon the photo- 

 graphic plate. 



This something is set in vibration by the sun, or 

 other star that is intensely hot. The undulations, or 



*J. Clerk Maxwell, Ency. Brit. 9th Edit. "Attraction." 

 124 



