PHYSICAL PARADOXES. 



conceive of a mechanical system based on push- 

 ing, direct or indirect, which should make it 

 possible for special vibrations of the particles 

 of a medium to cause the approximation of two 

 bodies surrounded by it. 



Let A and B (Fig. 42) be two particles of 

 material substance, and let the remaining 



FlG. 42.-APPARENT ATTRACTION IN GENERAL: THEORY OF 

 REPULSION. 



segments of the ring be particles of the medium 

 by which they are surrounded. A side view of 

 the particles of the medium, on an enlarged 

 scale, is shown in the centre of the ring. C and 

 D are massive joints connected on the prin- 

 ciple of the balls of a steam-engine governor, so 

 that, as the particle revolves on a horizontal 

 axis, these joints tend to fly apart by centrifugal 



192 



