MECHANISM OF NATURE 



same force makes a different change in different 

 substances, it must be because of the difference in 

 number of primary spheres which constitute the 

 different substances, or the difference in the form 

 necessarily assumed by the subdivisions of differ- 

 ent substances. 



Yet there remains ever that common parentage, 

 and the last essential equality of all matter, and 

 based on that last equality is the mass of any sub- 

 stance. 



Therefore, since no application of any known 

 force can change the weight of any substance, and 

 because no addition of P. S., in their void state, to 

 the bulk of any substance increases its weight. 



Therefore, etc. 



PROPOSITION VI. 



The combination of four primary spheres, each 

 to two others in the closest possible contact, con- 

 stitute the first form of organized matter. 



Because all material substance is built up of 

 primary spheres. (Prop. XIX, B. 1). 



Therefore, the last possible subdivision of any 

 substance, while it still remains an identical sub- 

 stance, is that number of primary spheres which 

 are held together in this new constructive identity, 

 the atom. 



And since that identity is constant through all 

 the changes which matter undergoes in our direct 



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