326 On the Possibility of Originating Wave Disturbances. 
resistance. The only experiments with which J am acquainted on the magnetic 
effects of such discharges seem to indicate a periodic law for the induction near the 
circuit. 
In the theory of sound it is known that the disturbances are propagated outwards, 
and that the energy of the vibrating body is gradually transferred to the medium, 
and so we know which solution to employ. If a body be sounding in the centre 
of a closed sphere of the right size during the time that the sound takes to reach 
the surface of the sphere, the first form of solution holds ; but as soon as the 
reflected wave combines with the direct one the second form is the right one. If 
the electro-magnetic action is analogous to this, 1t seems to follow that in infinite 
space where there is nothing to produce the reflected wave the first form of solution, 
in which all the energy is gradually transferred to the medium, is the right one to 
employ. Indeed it seems almost impossible without calling in the aid of some form 
of direct action at a distance to see how the stationary waves can be simultaneously 
originated throughout space. 
If, however, as is generally assumed, a system of perfect conductors carrying 
currents be a conservation system they cannot be analogous to a system such as a 
sounding body in air, for if they were and the currents vary in intensity they would 
eradually transfer their energy to the ether. In wy first paper on this subject I 
investigated it from this point of view. Assuming that the theory of direct action 
at a distance, and Maxwell’s of action through a medium, lead to the same results 
I showed that electric currents could not originate wave disturbances such as light. 
From my subsequent paper it is however clear that the assumption that the two 
theories lead to the same results is only true to the same order of approximation as 
omitting the mutual induction of the displacement currents in the non-conducting 
medium. This is evident from the fact that the equations for calculating the vector 
potential on the theory of direct action at a distance could never make it vanish short 
of infinity while the equations founded on Maxwell’s theory certainly lead to the con- 
clusion that either the energy is gradually transferred to the medium or else that the 
vector potential vanishes at each of a series of distances given by an equation of the 
form cos mr =0. Hence these papers at least show that contrary to the ordinary as- 
sumption the two theories do not lead to the same results, and they point out a 
direction in which to investigate which theory is true. It seems further highly 
probable that the energy of varying currents is in part radiated into space and so lost 
tous. It seems further probable that, contrary to what I have stated in my first 
paper, the interactions between the molecules of matter and the ether are of the 
same character as the electromagnetic actions with which we are acquainted. 
In conclusion I must apologize for having ventured to investigate these matters 
when I was so ignorant of what had already been done as to make mistakes requiring 
such serious corrections as are contained in this paper. 
