MECHANISM OF NATURE 



from all other portions of force that move other 

 particular identities at the same time. And so 

 natural seems this hypothesis and so interwoven 

 with every day experience that it seems scarcely 

 possible that this hypothesis is wrong. The brick- 

 bat, thrown at an offending head, leaves the hands 

 of the thrower with all the force transferred from 

 the thrower to the brick, and when the brick strikes 

 the head, all the force is transferred to the head. 

 And this transference of force from one body to 

 another body may be traced backwards of the 

 thrower infinitely, or rather it was always existing, 

 and it may be followed on from the head that was 

 hit, and it must go on hitting forever. And upon 

 this hypothesis is built up the wave motion myth- 

 ology of nineteenth century scientific evolution. 



But the brickbat in its flight was not cut off 

 from universal force, for it was acted upon by 

 gravity. And on both ends of this force-mani- 

 festation it was connected with a movement of 

 primary spheres in void matter. (Prop. VIII, 

 B. 3.) 



Again, the inertia of bodies is in strict relation 

 to their mass, so that by the momentum acquired 

 through a given amount of force, the mass of any 

 substance may be most accurately determined. 



Let a ball be suspended by a small wire or 

 thread. Then a slight push will set the ball in 

 motion, providing that the push is slow at first. 

 But it will take a heavy blow to set the ball into 

 rapid motion at once. 



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