354 Mr. Whelpley on the Idea of an Atom. 



By an idea, we escape empiricism, and begin to have a faith in 

 the unity of things ; invention, building upon this faith, antici- 

 pates Nature, and gives her forces new directions. 



There can be no other test for the value of an idea, than the 

 degree of order, which it brings, to the chaos of accidents. Test- 

 ing, by this rule, the idea of gravitation, it discovers the greatest 

 universality ; but the notion of an ether, independent of matter, 

 and able to impede its motion, seems wanting in the simplicity 

 of a first principle. The ether of the mathematicians is only a 

 more tenuous kind of matter, divided into particles. It is assum- 

 ed, that these particles are centres of mutual repulsion, and, that 

 they vibrate in a peculiar manner, producing radiant heat, and 

 the motions of light ; but no cause has been assigned for such 

 vibrations, or why light and heat should not be as readily trans- 

 mitted by an ether not divided into particles, as by one so di- 

 vided. It is certainly as easy to conceive a line, as a point, from 

 which repulsion shall originate equally on all sides; and a line of 

 this kind, in motion, if it be a circle enlarging itself, might rep- 

 resent the motion of light and heat as truly as it is represented 

 by a vibratile point : and it simphfies the idea of such a motion. 



If any one can conceive of an invisible force, they can ima- 

 gine that it operates in any mode or figure whatsoever. Let it be 

 supposed, that there is a point (C) taken in space, which shall be 

 the centre from which a force operates. If this force is spiritual, 

 it may act in any direction it pleases ; but, let it be material, 

 then it must operate in fixed directions, and at certain intervals 

 of time, and will be made sensible only when called into action 

 by some other force, like or unlike itself, which acts from some 

 other point in space. Suppose that there are but two such 

 points from which these imaginary forces act, and that the pow- 

 ers which act from them are of the same kind, and that the two 

 points are movable ; then will they both seek to occupy the 

 whole of space, (for they have the same relation to it,) and will 

 retreat farther from each other, ad infinitum. 



The conception seems to be of no use, for nothing comes of 

 it ; but thus much is gained, that a force acting from a centre, 

 m^ay fill the universe with its presence, and will appear at all dis- 

 tances wherever another of the same kind (or having the same 

 relation to space) may call it into existence. The points are 

 mere mathematical abstractions, but the forces are real ideas ; 



