REFLECTIONS AND CONCLUSION. 387 



primordial to its present condition. And every new 

 discovery, every new fact brought to light and correl- 

 ated with facts already known, will mean a step 

 forward ; will betoken progress, knowledge and en- 

 lightenment. 



As the old emission theory of light, originated 

 by Descartes and Newton, was followed by the un- 

 dulatory theory formulated by Huygens, Young and 

 Fresnel ; and as the latter has been succeeded by the 

 electro-magnetic theory of Maxwell and Hertz, so 

 likewise will the various theories which are now of- 

 fered in explanation of the facts of Evolution, be re- 

 placed by others which shall be a closer approxima- 

 tion to the truth, or which shall eventually exhibit 

 the truth in all its beauty and grandeur. The hy- 

 potheses of Darwin, Wallace, Spencer, Mivart and 

 Weismann will, no doubt, give way in greater or less 

 degree to other theories which, while being more in 

 conformity with the facts observed, shall afford a 

 truer view of nature and supply a more accurate 

 knowledge of those of her operations that are now 

 so mysterious and so ill-understood. The work to 

 be accomplished will, of course, be slow and require 

 time. For, unlike the theory of light, Evolution deals 

 not merely with one form of energy, or forms of 

 energy which are reducible to one. It is not con- 

 fined to the discussion of only a narrow and limited 

 range of phenomena, but is, on the contrary, a 

 theory which is universal in its application, embrac- 

 ing all forms of energy and dealing with all kinds of 

 matter, from simple elementary atoms to that high- 

 est and most complex of organisms, man. 



