Essay on Motion and Force. 



271 



demand. In short, the universe from that time forward 

 would he condemned to a state of eternal rest." 



This theory is remarkable in that it is thus indorsed by 

 one of the strongest advocates of the conservation of force, 

 and is a striking example of the way in which thought may 

 be shackled by language. Considering force as an occult 

 property of matter, and overlooking the fact, that in the 

 state of equilibrium to Avhich all forces converted into heat 

 must finally come, these forces having ceased to exist, heat 

 itself, considered as a force, must have also ceased to exist, 

 as otherwise we should have a cause without an effect, he 

 reaches this impossible state of all matter, absolute rest, 

 involving the idea of cessation of motion in matter with- 

 out a coresponding increase of motion in other matter ; 

 besides it does not follow, that because heat cannot be con- 

 verted wholly into mechanical work, that it cannot be 

 converted into other modes of motion, which in their term 

 shall be again converted into heat. I am also at a loss to 

 see how this state of absolute rest is compatible with the 

 definition of heat as given by the same writer," a shivering 

 motion of the ultimate particles of bodies." 



The terms action and reaction also, in their accepted mean- 

 ing, are faulty, conveying a wrong idea of the rationale 

 of motion. Bodies are never moved by the direct contact 

 of their surfaces. I need not dwell upon the foundation 

 for the doctrine that the ultimate particles of matter never 

 touch each other. But I will give as an additional argu- 

 ment in favor of this doctrine what I have never yet seen or 

 heard propounded as sustaining it, viz., the fact, that matter, 

 in all the states in which it is known to exist, admits of the 

 artificial separation of its parts. Whatever may be the 

 cause of the variation in attraction which I have before 

 noticed, viz., that the tendency of bodies to approach each 

 other varies as the square of the distance between the 

 centers of attraction, the conclusion seems inevitable that 

 did the molecules of matter ever come into actua con- 

 tact they would cohere with such force as to be insepar- 



