DISPLACEMENT 



PROPOSITION XII. 



Force is not inherent in matter. 



We know force through changes made in mat- 

 ter. (Axiom I.) Everywhere we see force trans- 

 ferred from one material body to another. 



Wherever force is exhibited, we perceive it only 

 as it changes from one body to another. 



And, however far we trace a force backward, 

 we find beyond the last change we can perceive 

 necessity for another change. 



The sun that causes all the varied earth life must 

 necessarily himself undergo a change; for we 

 know that he changes positions in the Universe. 



Again, we can measure the action of force, and 

 fully and accurately determine the amount of a 

 certain material, which must undergo a given 

 change to induce a certain change in a given 

 amount of another material (so many pounds of 

 alcohol burned will raise so many pounds of water, 

 through a given number of degrees of heat). 



Therefore, there is an exact equivalent between 

 any two manifestations of force. 



And, even with our imperfect appliances, we 

 can clearly see that no action of force, or no force, 

 as it is generally stated, can be lost out of the 

 Universe. 



But if force is inherent in matter, then if a 

 given amount of force has departed from a mate- 

 rial body, there must then be less remaining in 



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