Abstract: A gas fired kiln wherein symmetrically disposed and vertically oriented high velocity natural draft burners burn fuel within and immediately adjacent the side walls of the kiln's chamber, the flames extending vertically adjacent the side walls and the hot gases produced thereby traveling up along the walls to an arched crown chamber ceiling, the hot gases then traveling generally downwardly under the influence of a partial vacuum created by hot gases escaping the chamber through a flue opening centered at the base of the kiln's rear wall, the flue opening communicating with a vertical flue extending only to approximately exterior height of the arched crown of the kiln.