The Destiny of Man. 59 



the development and differentiation of suc- 

 cessive layers, gave place to the variously- 

 constructed eyes of insects, mollusks, and 

 vertebrates. The day for creative work 

 of this sort has probably gone by, as the 

 day for the evolution of annulose segments 

 and vertebrate skeletons has gone by, 

 on our planet, at least. In the line of our 

 own development, all work of this kind 

 stopped long ago, to be replaced by differ- 

 ent methods. As an optical instrument, 

 the eye had well-nigh reached extreme per- 

 fection in many a bird and mammal ages 

 before man's beginnings ; and the essential 

 features of the human hand existed already 

 in the hands of Miocene apes. But differ- 

 ent methods came in when human intelli- 

 gence appeared upon the scene. Mr. Spen- 

 cer has somewhere reminded us that the 

 crowbar is but an extra lever added to the 

 levers of which the arm is already com- 

 posed, and the telescope but adds a new 

 set of lenses to those which already exist in 

 the eye. This beautiful illustration goes to 



