NEW CONCEPTIONS IN SCIENCE 



the luminiferous i.e., light-bearing ether. Nowa- 

 days the heavy heads that bother themselves with 

 such matters see in a ray of light merely the pulsa- 

 tion or vibration of an intangible substance which 

 acts like a solid, but which lets ordinary matter 

 bricks and bread and people go through it just as 

 if it, or they, were a sieve. 



No one could ever count up what an amount of 

 time and trouble, of experiment and mathematical 

 calculation, has been spent to make this pure in- 

 ference turn out to be real and true. The idea has 

 been singularly fertile, and by its aid many simple 

 explanations are possible. It will give an easily 

 understood picture of the action of Signor Mar- 

 coni's wireless telegraph, of the Rontgen rays, the 

 invisible rays of heat, which Professor Langley, of 

 the Smithsonian Institution at Washington, has 

 studied so thoroughly, and much more. One of 

 the very latest books on physics opens with the 

 remark that all the actions and the phenomena 

 which are grouped under the name of energy, as 

 light, heat, electricity, and magnetism, have come 

 to be simply questions of the mechanics of this in- 

 explicable and contradictory substance, the ether. 



So at least matters stood when the late century 

 passed out. But now there is just a suggestion that 

 the present theory of the ether, gigantic alike in con- 

 ception and result, may likewise go the way of the 



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