DISPLACEMENT 



PROPOSITION VIII. 



The particles composing a liquid substance are 

 not in contact one with the other through any 

 ordinary degree of heat. 



Because the change from the solid to the liquid 

 state of any substance is sudden and radical. 

 Therefore, it is not merely a question of degree 

 of space between the particles of the same matter 

 in either state, for in both there is a wide range 

 of expansion, where a solid is still a solid, and a 

 liquid is still a liquid. 



Therefore, the change consists in the alteration 

 of the particles from being interlocked in the solid 

 substance, to being not interlocked in the liquid 

 state. 



Again, if the particles of a liquid substance are 

 not interlocked when first the substance assumes 

 the liquid state, and every degree of heat drives 

 them farther apart, because liquids expand by heat 

 (common experience) ; 



Then, the particles can only be in touch with 

 one another in that instant when they cease to 

 interlock. 



Therefore, the particles of a liquid substance are 

 not in actual contact one with another through 

 any ordinary degrees of heat. 



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