in EVOLUTION OF MACHINES 137 



to any other of the categories of our 

 knowledge. 



Mr. Spencer is under a complete 

 delusion if he supposes that the four or 

 five great heads of evidence, which he 

 specifies as all telling the same tale of 

 evolution, could not be equally applicable 

 to the facts if all the steps of evolution 

 were visibly and admittedly under the 

 ordering and guidance of a will. For 

 example, the argument founded on the 

 possibilities of Classification applies to 

 the evolution of human machines as well 

 as to the organic mechanisms of Nature. 

 A row of models of the steam-engine, 

 from " Papin's Digester " to the wonder- 

 ful machines which now drive express 

 trains at sixty or seventy miles an hour, 

 would show a consecutive series of de- 

 velopments in every way comparable 

 except in length and complexity with 

 the series of the Mammalian skeleton. 



