﻿Principles of Molecular Physics. 285 



approach of the two, their relative velocity will be equal to the sum 

 of the velocity of the earth and that due to their mutual attraction, 

 and, during their separation, will be equal to the difference of the same 

 velocities, and hence that the atom of aether will continue to attract 

 the molecule during a longer interval of time while the two are se- 

 parating than while they are approaching. The molecule will there- 

 fore on the whole be retarded by the action of the atom. If the 

 attractive aether be * immensely denser than the atmospheric air,' 

 the resistance should certainly not be less than that of a subtile re- 

 pulsive aether." 



This argument has one great defect : it is based on a false alle- 

 gation. It is not " my idea," nor has it ever been, that a mole- 

 cule of the earth's mass passes through the atom of aether and 

 leaves it behind. The earth in its path beats back and carries 

 before it the whole mass of aether upon which it impinges : and 

 the reason why it finds no resistance is not because it leaves the 

 aether behind, but because the aether itself is destitute of all re- 

 pulsive powers. This is a sufficient answer to the learned Pro- 

 fessor's objection. He will see that " by still holding to my line 

 of argument " I cannot be compelled, as he believes, " to abolish 

 the aether of space altogether/' 



Electric aether. — I had proposed two other questions on the 

 fundamental principles of Professor Norton's theory : the one 

 regarded the material continuity of gross matter, to which he 

 made a long reply, which I intend to examine in a future paper. 

 The other regarded the nature of his electric aether. I had 

 pointed out that this aether, being repulsive, could not attract 

 luminiferous aether ; and yet the author seemed to hold this 

 contradiction. 



He replies thus : 



" Professor Bayma has here entirely misunderstood me, and re- 

 presented what I threw out as a possible and perhaps probable con- 

 ception to be a fundamental principle of my theory." 



To this I have only to answer that I did not represent his con- 

 ception as a fundamental principle of his theory. I argued on 

 the contrary that this conception could not agree with the fun- 

 damental principles of his theory. A reference to my ' Molecular 

 Mechanics' (p. 188) will convince the reader of the truth of my 

 statement. As for misunderstanding him, I regret the fact if 

 true : of course Professor Norton is better qualified than I to 

 explain his own meaning. He says : 



" The real fundamental principle was that the atoms of electric 

 aether repelled each other ; and it was merely conjectured that this 

 repulsion might be due to atmospheres of luminiferous aether con- 

 densed around the electric atoms, instead of being a repulsive 

 action." 



