James’ and my retorts are based on the Anila stove designed by Professor RV Ravikumar of India. James cleverly combined the rocket stove and anila stove. Insulation is the key. I have, since the picture, added insulation under the barrel as well. I built many variations until settling with this. My horizontal design is easier to empty and the flue along the bottom gives a longer heat exchange area. Several gas entry holes are along each side of the bottom of the internal flue. The external finned air inlet, which I call a turbinator, swirls the primary air and significantly increases efficiency by enhancing the the third T of combustion: Time, Temperature and Turbulence. The glowing circle in the center of the turbinator is a sight glass. The startup time can be reduced to 20 minutes by directing a hair dryer or other blower Into the fire. This slight positive pressure from the blower also helps drive off moisture through the steam vent. When the venting gases sustain combustion, close the vent, install turbinator and let her rip (there is an audible roar). Pyrolysis continues for another 1 hour 45 minutes. Seal by replacing the turbinator with a duct plug, close the chimney damper and let cool.