on certain Theoretical Opinions. 51 



25. Does not your hypothesis require that the metallic par- 

 ticles, at opposite ends of the wire, shall in the first instance 

 be subjected to the same polarization as the excited particles 

 of the glass ; and that the opposite polarizations, transmitted 

 to some intervening point, should thus be mutually destroyed, 

 the one by the other? But if discharge involves a return to 

 the same state in vitreous particles, the same must be true in 

 those of the metallic wire. Wherefore then are these dissi- 

 pated, when the discharge is sufficiently powerful ? Their 

 dissipation must take place either while they are in the state 

 of being polarized, or in that of returning to their natural 

 state. But if it happen when in the first-mentioned state, the 

 conductor must be destroyed before the opposite polariza- 

 tion upon the surfaces can be neutralized by its interven- 

 tion. But if not dissipated in the act of being polarized, is it 

 reasonable to suppose that the metallic particles can be sun- 

 dered by returning to their natural state of depolarization ? 



26. Supposing that ordinary electrical induction could be 

 satisfactorily ascribed to the reaction of ponderable particles, 

 it cannot, it seems to me, be pretended that magnetic and 

 electro-magnetic induction is referable to this species of reac- 

 tion. It will be admitted that the Faradian currents do not 

 for their production require intervening ponderable atoms. 



27. From a note subjoined to page 37 of your pamphlet, 

 it appears that " on the question of the existence of one 

 or more imponderable fluids as the cause of electrical phse- 

 nomena, it has not been your intention to decide." I should 

 be much gratified if any of the strictures in which I have been 

 so bold as to indulge, should contribute to influence your ul- 

 timate decision. 



28. It appears to me that there has been an undue dispo- 

 sition to burden the matter, usually regarded as such, with 

 more duties than it can perform. Although it is only with 

 the properties of matter that we have a direct acquaintance, 

 and the existence of matter rests upon a theoretical inference 

 that since we perceive properties, there must be material par- 

 ticles to which those properties belong; yet there is no con- 

 viction which the mass of mankind entertain with more firm- 

 ness than that of the existence of matter in that ponderable 

 form, in which it is instinctively recognised by people of 

 common sense. Not perceiving that this conviction can only 

 be supported as a theoretic deduction from our perception of 

 the properties; there is a reluctance to admit the existence of 

 other matter, which has not in its favour the same instinctive 

 conception, although theoretically similar reasoning would 

 apply. But if one kind of matter be admitted to exist because 



E2 



