212 Prof. W. A. Norton on the Fundamental 



without changing their character, to represent a current of free 

 electricity. Again, they must be capable of propagation from 

 molecule to molecule with a continued reversion of their cha- 

 racter, to explain the phenomena of induction. Still, again, 

 these atomic or molecular motions must take place simultane- 

 ously with some other mode of motion, answering to heat, and 

 another, representative of the magnetic or diamagnetic condition ; 

 and these different modes of motion must be convertible each 

 into every other, &c. So far from being led into a region of 

 attractive simplicity, the complexity of the scene that presents 

 itself to the mind's eye would seem to be enough to appal the 

 most determined explorer in the field of speculative science. 



(3) It is conjectured by some physicists that the luminiferous 

 ffither may be equal to the duty assigned to the electric. But 

 no approximation to a successful attempt has yet been made to 

 realize this idea. It is a mere conjecture, and therefore un- 

 worthy of serious regard. 



My own position on the question of the existence of an electric 

 aether was not, as intimated by Professor Bayma, that it is an 

 established truth, at least with the same degree of certainty that 

 the existence of a luminiferous aether is, but an hypothesis (and 

 the only definite hypothesis hitherto suggested by electric phe- 

 nomena) which had been shown to be in accordance with the en- 

 tire range of such phenomena, and thus come to be generally 

 received. If it be true, as I maintain, that the molecular forces 

 and molecular phenomena generally, in all their interdependence 

 and mutual convertibility, can be derived from this hypothesis, 

 when this shall come to be acknowledged it will then be admitted 

 that full confirmation of the principle reached by induction has 

 been furnished by the deductive test. The existence of an elec- 

 tric sether will then become an established truth in the most po- 

 sitive sense in which this can be affirmed of any principle in 

 physics. 



Origin of Heat. — In expressing the strong conviction that 

 heat does not originate in the vibrations of gross molecules, re- 

 ference was had to vibrations of the molecules as a whole, to the 

 one side and the other of the positions of equilibrium. What is 

 meant by " vibrativity " I do not fully comprehend. If we are 

 to understand by it an alternate contraction and expansion of the 

 repulsive envelope of a molecule, then Professor Bayma' s theory 

 of heat bears a certain analogy to my own, and may, for all that 

 appears to the contrary, be free from the objections that may be 

 urged against the doctrine that heat consists in a true vibration 

 of atoms or molecules. 



Luminiferous JEtlicr. — There need be no hesitation as to the 

 proper answer to be made to our author's argument to show that 



