Energy in the Electrodynamic Field. 399 



oscillation they are determined by the vectors E, H o£ electric 

 and magnetic force whose components, referred to a spherical 

 polar coordinate system with origin at the vibrator and polar 

 axis along its line o£ symmetry, are 



p _2cos6> , ,, 



E,=^0Y f + rf), 



wherein dashes denote differentiations of f(x) with respect 

 to its argument a?, which in all cases is taken to be equal to 

 (ct-r). 



These expressions are derived in the usual way From a 

 scalar potential 



and a vector potential with components 

 cos j.,, ± v 



. sin0 j, f/ . v 



Im ithis case the components of the total current at the 

 typical field point are 



r ccosO / ,, ^ 



0. = ^W , + rf' + f/ , ) > 



the sethereal constituent being the only one existing. 



Thus on the general form of the new theory, the energy 

 density at the typical field point is given by 



