A method for the treatment of matter by plasma action to produce a glassy product. A plurality of electrode structures are positioned to define a reaction zone associated with the inter-electrode space. The inter-electrode space is conditioned (as by preionizing) and a series of discrete electrical discharges are produced throughout the reaction zone. In a preferred embodiment, the reaction zone is subjected to a sequence of discrete electrical discharges in a time interval less than the residence time of material to be treated within the reaction zone.