PHYSIOLOGICAL PARADOXES. 



we call moving a substance really corresponds 

 to the appearance of moving the red spot in our 

 field of boards. It may mean setting in motion 

 some machinery not yet understood which 

 controls the vibrations of the ultimate par- 

 ticles of matter as our wires and motors control 

 the turning of the boards in our field. 



In that case, when the phenomenon occurs 

 which appears to us the movement of an object, 

 what actually happens is that the special 

 vibrations which have produced the appear- 

 ance of the various qualities of the object cease 

 in the particles which have been their seat, 

 and are immediately communicated to the 

 adjoining particles in one direction. These 

 in their turn pass them on to the next, and they 

 to the next, and so on while the energy which 

 set up the transference lasts. Thus the ap- 

 pearances of the body move through spaces 

 which are far less than microscopically small 

 ones, depending upon the sizes of the ultimate 

 particles or the distances between them. These 

 movements are separate and distinct jumps, 

 like the movement of the red spot from one 

 row of boards to the next. But the jumps are 

 so small that, though the succession of a suffi- 

 cient number of them produces a visible move- 

 ment, the separate advances are not detect- 

 able by our most delicate instruments, much 

 less by our senses, and so the movement appears 

 to have smoothness and continuity. 



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