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The purpose of this investigation was to measure the limits with regard to currents and time duration of the glow and arc modes for the low current discharge at atmospheric pressure. In addition, some indications were obtained as to the conditions at the cathode which lead to such transitions. Accurate measurements in the normally unstable transition region were made possible through the use of a current stabilized power supply, together with special instrumentation for determining the magnitude and duration of the arc or glow voltage for periods as short as 0.02 microsecond. It is shown that glow‐arc transitions can occur for currents as low as 0.002 amp and for currents at least as high as 1.0 amp in the atmospheric pressure argon discharge. The duration of the arc mode at low currents is usually less than 5 microseconds. These low current transitions occur only when an oxide film is present on the cathode and are caused by the action of high fields created by positive ions across the bulk of the thin oxide films.