Dr. Faraday's Thoughts on Ray-vibrations. 347 



of miles apart; further, atoms which, to our knowledge, are 

 at least nineteen times that distance, and indeed, in cometary 

 masses, far more, are in a similar way tied together by the 

 lines of force extending from and belonging to each. What 

 is there in the condition of the particles of the supposed aether, 

 if there be even only one such particle between us and the 

 sun, that can in subtilty and extent compare to this ? 



Let us not be confused by the ponderability and gravitation 

 of heavy matter, as if they proved the presence of the abstract 

 nuclei; these are due not to the nuclei, but to the force su- 

 peradded to them, if the nuclei exist at all ; and, if the ather 

 particles be without this force, which according to the assump- 

 tion is the case, then they are more material, in the abstract 

 sense, than the matter of this our globe ; for matter, accord- 

 ing to the assumption, being made up of nuclei and force, 

 the aether particles have in this respect proportionately more 

 of the nucleus and less of the force. 



On the other hand, the infinite elasticity assumed as be- 

 longing to the particles of the aether, is as striking and posi- 

 tive a force of it as gravity is of ponderable particles, and pro- 

 duces in its way effects as great; in witness whereof we have 

 all the varieties of radiant agency as exhibited in luminous, 

 calorific, and actinic phaenomena. 



Perhaps I am in error in thinking the idea generally formed 

 of the aether is that its nuclei are almost infinitely small, and 

 that such force as it has, namely its elasticity, is almost infi- 

 nitely intense. But if such be the received notion, what then 

 is left in the aether but force or centres of force? As gravita- 

 tion and solidity do not belong to it, perhaps many may ad- 

 mit this conclusion ; but what is gravitation and solidity? cer- 

 tainly not the weight and contact of the abstract nuclei. The 

 one is the consequence of an attractive force, which can act 

 at distances as great as the mind of man can estimate or con- 

 ceive ; and the other is the consequence of a repulsive force, 

 which forbids for ever the contact or touch of any two nuclei; 

 so that these powers or properties should not in any degree 

 lead those persons who conceive of the aether as a thing con- 

 sisting of force only, to think any otherways of ponderable 

 matter, except that it has more and other forces associated 

 with it than the aether has. 



In experimental philosophy we can, by the phaenomena 

 presented, recognise various kinds of lines of force ; thus there 

 are the lines of gravitating force, those of electro-static indue- 

 tion, those of magnetic action, and others partaking of a dy- 

 namic character might be perhaps included. The lines of 

 electric and magnetic action are by many considered as exerted 



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