This paper describes a method for the measurement and photographic recording of electron density loss in an ionized gas utilizing a microwave system operating near 9400 Mc. The region between initial density level (upon removal of a 24.5‐Mc ionizing voltage) and 500 &mgr;sec later was investigated. Examples of results obtained for commercial neon using this method of measurement are included. In general, it was observed that for commerical neon 90&percent; of the electron density loss occurred within the first 250 &mgr;sec after removal of the ionizing voltage. The equipment used along with photographs of the arrangment, and the results obtained are discussed briefly.