376 Dr. E. Goldstein on the Electric 



vibrations ; here, on the contrary, a motion of the aether 

 which does not consist of transversal vibrations is converted 

 into transversal vibrations. We have, however, a phenome- 

 non analogous to this in acoustic resonance, where we see the 

 longitudinal motions of particles of air transformed into the 

 transverse vibrations of a resounding string. (2) I am dis- 

 posed to reject the name phosphorescence for the phenomena 

 under consideration, because, according to all the ideas which 

 we have so far associated with the name phosphorescence, an 

 hypothesis as to the temperature-conditions of the discharge 

 would be introduced by the choice of this name, since the 

 temperature of a gas is always supposed to be lower than that 

 of a gas of like emissive power rendered luminous by heat. 

 But this, even assuming that the conclusions of E. Wiede- 

 mann as to the temperature of the discharge should be con- 

 firmed by further experiments, is not yet accepted as the true 

 character of the light of the discharge; and my speculations 

 on the nature of the discharge do not in any way prejudice 

 the question of the temperature of the discharge. For the 

 present I leave this entirely out of the discussion. 



The assumption that a vacuum conducts electricity has con- 

 sequences which are far-reaching, especially in the domain of 

 cosmical physics. The usual fate of attempts to found a 

 cosmo-physical theory upon experimental results is scarcely 

 such as to encourage imitators. At the same time I venture 

 to point out at least so much as this, that certain terrestrial 

 phenomena of an electric or magnetic nature which, because 

 of the coincidence of their periods or epochs with solar 

 changes, have been explained as due to the statical influence, 

 magnetic induction, &c. of the sun's mass, might possibly be 

 more conveniently referred to electric currents radiating 

 through interplanetary space from the central body. Expe- 

 riment shows no limit to the expansion of that remarkable 

 motion which we observe in the kathode-rays as we eliminate 

 the ponderable medium more and more completely — it is 

 conceivable that the sun radiates electric rays as well as light - 

 rays through space. We see that even when the two poles 

 are placed close together, the kathode-rays stream out into 

 space without limit, without reference to the position of the 

 anode; consequently for electrical communication with the 

 sun, it would not be necessary that the earth should be the 

 source of electricity or pole of the current, but discharges for 

 which both poles are situated on the sun might produce rays 

 radiating from the sun into space. 



