September 19, 1913] 



SCIENCE 



395 



is involved in these effects, it may be held 

 that the detection of a uniform drift of the 

 solar system in this way is not contrary to 

 the principle of relativity. It is contrary 

 to some statements of that principle; and 

 the cogency of those statements breaks 

 down, I think, whenever they include the 

 velocity of light; because there we really 

 have something absolute (in the only sense 

 in which the term can have a physical 

 meaning) with which we can compare our 

 own motions, when we have learned how. 



But in ordinary astronomical translation 

 — translation as of the earth in its orbit — 

 all our instruments, all our standards, the 

 whole contents of our laboratory, are 

 moving at the same rate in the same direc- 

 tion ; under those conditions we can not ex- 

 pect to observe anything. Clerk Maxwell 

 went so far as to say that if every particle 

 of matter simultaneously received a gradu- 

 ated blow so as to produce a given constant 

 acceleration all in the same direction, we 

 should be unaware of the fact. He did not 

 then know all that we know about radia- 

 tion. But apart from that, and limiting 

 ourselves to comparatively slow changes of 

 velocity, our standards will inevitably 

 share whatever change occurs. So far as 

 observation goes, everything will be prac- 

 tically as if no change had occurred at all 

 — though that may not be the truth. All 

 that experiment establishes is that there 

 have so far always been compensations; so 

 that the attempt to observe motion through 

 the ether is being given up as hopeless. 



Surely, however, the minute and curious 

 compensations can not be accidental, they 

 must be necessary? Yes, they are neces- 

 sary ; and I want to say why. Suppose the 

 case were one of measuring thermal expan- 

 sion ; and suppose everything had the same 

 temperature and the same expansibility; 

 our standards would contract or expand 

 with everything else, and we could observe 



nothing ; but expansion would occur never- 

 theless. That is obvious, but the following 

 assertion is not so obvious. If everything 

 in the universe had the same temperature, 

 no matter what that temperature was, 

 nothing would be visible at all; the ex- 

 ternal world so far as vision went, would 

 not appear to exist. Visibility depends on 

 radiation, on differential radiation. We 

 must have differences to appeal to our 

 senses, they are not constructed for uni- 

 formity. 



It is the extreme omnipresence and uni- 

 formity and universal agency of the ether 

 of space that makes it so difficult to ob- 

 serve. To observe anything you must have 

 differences. If all actions at a distance are 

 conducted at the same rate through the 

 ether, the travel of none of them can be 

 observed. Find something not conveyed 

 by the ether and there is a chance. But 

 then every physical action is transmitted 

 by the ether, and in every case by means of 

 its transverse or radiation-like activity. 



Except perhaps gravitation. That may 

 give us a clue some day, but at present we 

 have not been able to detect its speed of 

 transmission at all. No plan has been de- 

 vised for measuring it. Nothing short of 

 the creation or destruction of matter seems 

 likely to serve; creation or destruction of 

 the gravitational unit, whether it be an 

 atom or an electron or whatever it is. Most 

 likely the unit of weight is an electron, 

 just as the unit of mass is. 



Oliver Lodge 

 (To he concluded) 



A SUMMARY OF THE WORK OF THE V. S. 



FISHERIES MARINE BIOLOGICAL 



STATION AT BEAUFORT, N. C, 



DURING 1912 



The laboratory of the Bureau of Fisheries 



at Beaufort, North Carolina, was open as 



usual during the summer of 1912, and opened 



about the middle of June, 1913, to investiga- 



