An experimental investigation of the electric-field strength along the length of a cascade argon at a pressure lower than atmospheric pressure has been performed. The influence of different processes on the formation of the voltage-current and E-I characteristics of the arc was considered. It is shown that the processes of heat transfer are of primary importance; however, in the region of mixing of the cathode jet with the heated gas the Reynolds number has a marked influence. The generalized characteristics of the voltage across the arc, of the near-electrode voltage drop, and of the electric field strength averaged over the length are presented.