The Calorimetric Study of the Arc

The present paper describes an attempt to determine the distribution of energy in the electric arc by the calorimetric method. The total energy input to the arc was measured by a specially calibrated watthour meter. The energy dissipated at the anode and at the cathode was estimated by the temperature rise of the electrodes, which was measured by mercury thermometers. In experiments with the iron, copper, and carbon arcs, the anode and cathode were of the same weight and shape and were provided with an identical heat insulation. Since the ratio between the energies dissipated at the anode and at the cathode was made independent of the losses by radiation and the absolute values of energies involved, its determination was made with sufficient accuracy. In the case of iron or copper arcs in air this ratio was found to be practically unity. The presence of different fluxes alters the distribution of energy between the anode and cathode. In the case of an arc maintained between graphite electrodes, the energy at the anode was much higher than that at the cathode.