The investigation of the lithium effect on the temperature distribution of the arc is presented. Measurements were carried out by the Schlieren interference method to about 4000°K. The arc free burning in nitrogen was observed and the results of temperature measurements, carried out with and without lithium addition, were presented. Lithium was added to the arc by anode evaporation. Temperature measurements in outer areas were connected to previously presented spectroscopical measurements in the central part of the arc. The lithium addition affects the increase of the electroconductive central part of the arc.
