414 Dr. A. H. Buclierer on a New Principle 



modify the Maxwellian theory in such a manner as to elimi- 

 nate the effects of translator}' motion have admittedly failed. 

 Now the author, guided by the feeling that the form of the 

 Maxwellian equations must correspond somehow to the true 

 laws of electromaghetism, has attempted a new interpretation 

 of these equations that should harmonize with facts. 



In the following the author will show how this task can 

 be accomplished. We consider two electromagnetic systems 

 A and B in uniform rectilinear motion relatively to each 

 other. Then, whenever we speak of the dynamical inter- 

 action of the systems we stipulate that the system acted upon 

 — we will call this henceforth the passive system, and ac- 

 cordingly the other system the active one — experiences the 

 same force as it would in the Maxwellian theory on the 

 assumption that it were at rest in the cether and the other 

 system moving relatively to it. As will be shown later on, 

 the stipulation that the passive system is invariably the 

 system " at rest " implies the principle of relativity. 



§ 2. The Maxwellian equations as adapted to the electron 

 theory have this form for empty space : 



(I-) ~f t =curlE, 



(II .) -j- = v 2 curl H — 4:7rv 2 pvL, 



(III.) V H=0, 



(IV.) VE = 0, or = 4:7:v 2 p. 



As in the Maxwellian theory, H and E are the field inten- 

 sities measured in the system " at rest." The forces exerted 

 by the active system are purely electrical or magnetic. 

 There are no electrodynamic forces on a passive system. 

 We will limit our investigation for simplicity to rigid systems. 

 The total force exerted on the passive system takes the form 



(V.) F=jjH<r„^+ ^E pdr. 



Here cr m means the surface-density of magnetism ; dg is 

 an element of surface, and clr an element of volume. While 

 H and E are due to the active system, a m and p belong to 

 the passive system. 



We will now proceed to apply our equations to the rela- 

 tive motion of electrons and fictitious magnetic poles. We 

 thus obtain so-called point laws which by suitable integra- 

 tions can be employed to find the ponderomotive forces for 

 any distribution of electrical and magnetic masses of systems 



