206 FORCE AN AFFECTION OF MATTER. 



thing but an affection of matter, including the sether. 

 To speak of points or lines of force as the physical 

 cause of cosmical phenomena without any substance, 

 which is not force, underlying them, is inadmissible, 

 and seems as repugnant to common sense as the idea 

 of motion without something to be moved.* There is 

 no mystery about force in the sense of its being above 

 and beyond our intelligence, like the things pertaining 

 to the spiritual world, but there is much that is yet 

 hidden till we get a clearer knowledge of the physical 

 natures of the sether and of the atoms of matter. 



* " All the least parts of all bodies are extended, hard, impenetrable, 

 nd indued with vis inertia" Challis quotes this passage from New- 

 ton and adopts it, as likewise Newton's theory of an sether which, 

 however subtle, is composed, like air, of parts which mutually press. 

 The idea of an atom as an extended body, with infinite hardness and 

 strength, is not now entertained by physicists in general, but still, as 

 stated by W. Thomson, " we must realize it as a piece of matter of 

 measurable dimensions, with shape, motion, and laws of action, intel- 

 ligible subjects of scientific investigation" (" Brit. Assoc.," 1871). 

 Helmholtz's theory of vortex -motions in an incompressible frictionless 

 fluid is now looked to most hopefully, as likely to give the true idea of 

 the nature of the atoms : but this does not countenance the notion of self- 

 existent force, for the sether itself is material. Mr.Macvicar, in his original 

 and profound " Sketch of Philosophy," No. II., postulates the sether as 

 consisting of disci'ete spherical particles, all equal ; and that the mate- 

 rial elements are built up of clusters of these, forming units, and again 

 combinations of these units into certain stable shapes, forming the 

 elemental atoms. Dr. Samuel Brown favours Boscovich's well-known 

 hypothesis of points of repulsive and attractive forces, and of these he 

 (S. B.) supposes five spheres of alternate attractions and repulsions, 

 which are since nearly paralleled by Challis's series of sethereal waves 

 of attraction and repulsion. But when pressed to explain the 

 nature of this ultimate repulsion without substance, S. Brown used to 

 give utterance to the following sublime conception, which I cannot 

 refrain from repeating, although I do not find it in his published works. 

 The ultimate repulsion constituting the extension and impenetrability 

 of the atoms of matter, could be conceived of in no other way than as 

 the persistent exercise of the Will of God Himself, " in whom we live, 

 and move, and have our being," and which, if but for an instant with- 

 drawn, the whole material universe and its forces, in all their vast- 

 ness, glory, and beauty, would collapse and sink in a moment into their 

 original nothingness. 



