Abstract: An incinerator, comprises a combustion chamber having a pair of opposed side walls and a top outlet passage. Primary air is injected into the combustion chamber through the floor and air jets located in each side wall adjacent the outlet passage direct air streams across the chamber above the material being burned. The air jets on one of side walls are longitudinally offset relative to the air jets on the other side wall along the length of the chamber so that the air streams traversing the chamber from one side wall do not directly interfere (except at their outer peripheries) with the air streams from the other side wall and the air streams as they approach the side walls are directed downward toward the bottom of the chamber and tend to flow into and upwards along the surface material being burned.