we get instead of (63)
{ rot H′ - ∂E′/∂_t_ = _i_
(63a) {
{ div E′ = ρ
The equations (60), (62) and (63) give thus a generalisation of
Maxwell’s field-equations in vacuum, which remains true in our chosen
system of co-ordinates.
_The energy-components of the electro-magnetic field._