Supplement to Nature t^' 



No. 2805 



( 



AUGUST 4, 1923 



The Ether and Electrons.^ 

 By Sir Oliver Lodge, F.R.S. 



Preliminary. 



I HAVE been asked to speak on possibilities of 

 research in pure physics, and I rejoice that 

 attention has always been paid to the vital importance 

 of pure science in an Institution the backbone of the 

 work of which must be of a metrical character connected 

 with industrial applications, and much of it necessarily 

 subject to routine. 



The main lines on which physics has recently and 



[is still so rapidly advancing are well known. There 



lis no need to direct attention to such inquiries as are 



[the direct outcome of radioactivity, in its various 



Iforms spontaneous and induced : problems which 



i range from atomic investigations like those which 



Igo on in the Cavendish Laboratory, through X-ray 



|and ordinary spectrum analysis, down to the various 



ievices of wireless telegraphy. In all these things 



|there are among the members of the staff of the National 



lysical Laboratory, and on the Governing Body, 



[lore than competent advisers. 



I must just deal with such ideas as have been occupy- 



*ing my attention of late. I have found it interesting 



recently to look up some forgotten remarks of my 



own — made soon after a National Physical Laboratory 



was decided on, but before it was founded — in the 



preliminary portion of a presidential address to the 



Physical Society of London on February 10, 1899, 



as reported in the Proceedings of that Society, vol. xvi. 



Part VI., June 1899. Among other things there 



referred to, is a suggestion by FitzGerald that circularly 



polarised light sent through an absorbing medium 



might constitute it a magnet — a discovery not yet 



made. I see there also a reference to a Blue-book of 



1898 recording a Government conference about the 



founding of this Laboratory, Sir Richard Glazebrook 



has also kindly directed your attention to my address 



to Section A of the British Association at Cardiff in 



189 1, in which the foundation of a National Physical 



Laboratory was specially advocated. 



' From an address on " Some Possibilities for Research in Pure Pljysics, 

 especially on the Ether," delivered to the staff of the National Physical 

 Laboratory on March 14. The first section of the lecture is omitted for laclc 

 of space. It dealt with possible research in boundary or overlapping regions 

 of specific sciences, and on the relation between physics on one hand, and 

 chemistry, physiology, and biology on the other. ITiis section, and one 

 giving further details about the possibility of a renewed attempt to detect 

 or to disprove an ether flow along lines of magnetic force, will 1m; published 

 elsewhere. 



Properties of the Ether. 



The question of what constitutes a distinction 

 between physics and chemistry is difficult to decide, 

 but in general it may be said that chemists deal 

 chiefly with static relations and groupings, while 

 physicists are more inclined to treat phenomena 

 kinetically. Another clear distinction, at any rate 

 at present, between these two sciences is that one 

 deals with matter only, and the other deals with the 

 ether also. It seems that the electric charge is the 

 unifying or connecting entity between matter and 

 ether. Uncharged matter appears to have no effect 

 on ether at all. But its charged particles, or electrons, 

 in so far as they quiver or rotate, do disturb the ether 

 and generate waves in it. Moreover, if they revolve 

 or travel, as by locomotion, they generate magnetism 

 in it ; and . even when they are stationary, they 

 generate in it or rather are inevitably accompanied 

 by what is called electric force. That is, they appear 

 to attract or repel each other from a distance. Further- 

 more, for some reason — which I and some others think 

 to be residual electric or possibly magnetic attraction, 

 — they exert over minute ranges the force known as 

 cohesion, which again must be exerted entirely through 

 the ether, since particles of cohering matter are not 

 in contact. And again they exert, even at the most 

 enormous distances known to astronomy, the minute 

 residual force known as gravitation ; which in the case 

 of bodies of astronomical size amounts to a force of 

 gigantic magnitude. 



Light, magnetism, cohesion, -gravitation, — all these 

 are affairs of the ether, and are all studied in physics. 

 A superstition has recently arisen that the ether is 

 an exploded heresy, and is unnecessary ; but that 

 is an absurd misunderstanding. The theory of 

 relativity says nothing of the kind. As a mathe- 

 matical method it need not mention the ether, any 

 more than Laplace in his " System of the World " 

 felt that he need mention the Creator. He was 

 entirely within his rights in ignoring the Deity ; and 

 so is a relativist in ignoring the ether ; at least when 

 neither attempts to philosophise on that basis. For 

 ignoring a thing is not the same as putting it out of 

 existence. Extinction is as impossible to us as 

 Creation. We have to take things as we find them : 

 and we find ourselves imbedded in ether and matter. 

 So we had better make the best of it. 



Present Knowledge about Ether. 

 How much do we know about the ether, and how 

 much is it possible to ascertain ? We do not know 

 as much as we ought, but we know a few things ; 

 and we hope by further investigation to know more. 



E3 



