Electromagnetic energy and power in terms of charges and potentials instead of fields

Endean comments on the contribution to electromagnetic theory made by Carpenter (See ibid., vol.136, no.2, p.55-65, 1989). He concludes that Carpenter´s approach does lead, on occasion, to simplification of engineering calculations but, as an alternative formulation of electromagnetic theory, it is flawed. In reply, Carpenter pays tribute to Endean´s comments, particularly in summarising the phi , A approach in 4-tensor terms and proving the gauge invariance. However, he is puzzled by Endean´s conclusion and examines some of the points in detail.