292 FROM NEBULA TO NEBULA 



Again, suppose, in passing along a walk flanking the 

 precipitous side of a hill, you should notice a loose stone 

 just above your head menacing the safety of passers-by 

 and that you should reach up and gently lower the stone 

 to the level of the walk. In this case, by lowering the 

 stone slowly and by laying it softly on the ground you 

 will have done two things; (1) destroyed so many units 

 of your muscular energy, and (2) destroyed about an 

 equal number of the potential units of the stone but 

 without, however, adding a single unit of any other sort 

 of energy in substitution. Or, by way of variation, sup- 

 pose you were to lift the dumb-bell to arm's length, but 

 instead of dropping it or lowering it at once you were to 

 keep holding it aloft until you grew weary, and then to 

 lower it again with the utmost slowness, could any 

 Stewart or Soddy convince you that the energy units 

 gained by this stunt exactly counterbalance the muscular 

 effort you have put forth? 



Energy being, according to my conception, an act or 

 manifestation of matter itself instead of an intangible 

 something acting through matter, it follows that these 

 acts or manifestations are indefinitely repetitive in char- 

 acter. As long as matter exists it will manifest itself. 

 Energy is not matter, nor matter energy, but MATTER is 



ENERGETIC. 



To illustrate : It is Newton himself who is entitled 

 to the credit of originating the conception that the 

 earth's gravity holds the moon in perpetual leash, and 

 that were this power to run out or forget to act, even for 

 a second, the moon would fly off into space. What, then, 

 can be plainer than that the unique force of gravitation 

 is creative, that it evolves afresh in every new instant of 

 time, and that they who deny the existence of such a 

 source of vitality and recuperation in Nature simply mis- 

 state the fact? But Newton confined his attention to 

 only one side of the shield; he considered only the mat- 

 ter of centripetal force, but the centrifugal he left to tele- 

 ological speculations. Now, a creative force on one side 

 serving as the "action" can be evenly counterbalanced 

 on the other only by a like creative force to serve as the 



