MECHANISM OF NATURE 



displacement because they can act through matter 

 only. (Axiom I.) It is then undoubtedly an ad- 

 vantage in the consideration of identical forces to 

 look upon force as displacement; to consider so 

 much universal space vacated as so much force 

 brought into play. 



And because every movement is connected on 

 both sides with a movement of void matter, the 

 question of intensity and duration of movement 

 of any organized body resolves itself into the ques- 

 tion, "How many organized bodies, and how many 

 primary spheres of void matter are affected by 

 the movement, and divide the total pressure be- 

 tween themselves ? " 



For a dead pressure becomes motion only when 

 something yields to it, and before anything can 

 yield it must have somewhere to go to. If the 

 Universe were one whole body, then any change 

 that it might undergo would have to be instanta- 

 neous. 



But we cannot conceive how anything composed 

 of particles can change instantaneously, when one 

 particle must change before the other can move. 



And because 10 spheres of water in our hydraulic 

 jack cannot fill the whole space vacated by a thou- 

 sand spheres of equal diameter, therefore, the ten 

 must get 990 to help them ; the little rod of Figure 

 A must move 100 times as far as the larger to 

 multiply the pressure upon it a hundredfold. 



Then looking upon all manifested force, per- 

 ceptible to us directly, as the result of displace- 

 106 



