His method of firing is substantially different enough from a standard electric or gas kiln that it's more in tune with pit firing, which is what ceramicists call it when you just build a hole in the ground and make a fire in it and toss the pots in.
This is, of course, slightly abstruse if you aren't into the nitty gritty of it, but suffice to say, if you said his stack of bricks on the ground was a kiln, many people would be confused.
No worries it's kind of a technical field, with some interesting high temperature chemistry, but if you really want to capture what our ancestors did thousands of years ago, Andy Ward is really a wonderful resource. He does a lot of native clay harvesting and very local recreations of ancient techniques, sort of "experimental archaeology" stuff.
It's not what I do, but I've learned a lot from him even with sort of "as unrelated as you can get" ceramics focuses (I mostly work in thrown porcelain, with electric firing and fancy glazing techniques).
This is, of course, slightly abstruse if you aren't into the nitty gritty of it, but suffice to say, if you said his stack of bricks on the ground was a kiln, many people would be confused.