PHYSIOLOGICAL PARADOXES. 



must begin by remembering that matter is not 

 continuous. The hardest crystals, the most 

 ductile metals, the clearest liquids, all con- 

 sist of invisibly small molecules separated by 

 numerous spaces. The molecules are built up 

 of separate atoms which also have much free- 

 dom of movement within the molecules. The 

 atoms themselves consist of minute corpuscles 

 which have relative motions of the greatest 

 activity and occupy individually much less 

 space in the atom than one gnat does in a 

 swarm of gnats. So far from continuous is 

 the structure of even the densest and heaviest 

 elements, such as uranium, radium, platinum, 

 gold and lead. It is possible, and even prob- 

 able, that the corpuscles themselves consist of 

 still smaller particles or granules which have 

 as free movement, relatively to each other, 

 as have the corpuscles which form atoms. 



Now, it is quite conceivable that there may 

 be a limit to the smallness of particles or 

 granules of matter. It is difficult, indeed, 

 to conceive that there should not be such a 

 limit. There was, it is true, a time, and that 

 not very long ago, when it was more natural to 

 believe that there was no such limit. We could 

 crush a piece of sugar into small pieces, each 

 of these into smaller, and with the assistance 

 of smooth, hard surfaces and a microscope, we 

 could effect and prove still further subdivision. 

 So that it seemed fair to say that the only limit 



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