Observations of the electron density, visible and near ultraviolet light intensity, and spectrum associated with a 2800-Mc pulsed electrodeless discharge through mercury vapor have been made. Our results indicate ambipolar diffusion as the principal mechanism of electron removal at low pressure, with attachment becoming increasingly important at higher pressure. The data also yield a considerable amount of information regarding electron temperatures, recombination coefficient, and other parameters necessary to a detailed description of the processes taking place in the discharge.