Yes the stumps design is a gravity feed. The top of the chute is sealed so that the coal doesnt burn all the wayup. There is a valve in the lower ash box door that lets air in and is used to control the heat. A transfer tube runs from just above the grate to into the cooking cahmber. You can see it along the bottom. It is a very efficient design. I am using about a pound of coal per hour at 250-260 degrees.