I understand now. Since the anth did not clinker like the bit coal, the operation was different. Ash pan with anth. Makes sence.
I believe that I was wrong on the name of the parts. What might be called the pot [or retort?] is different between the two?
Fwiw: Again, the Iron fireman [and other brands] of underfed stokers are still common here. The bit coal around here varies widely, and so the ease of use can range widely too. My Iron fireman was mated to a small boiler, with a fire box that was apx 20" x 22". I found it to be more finicky with the small firebox. Fellows that have larger boilers seem to have not have as much problem using less than ideal coal, compared to my old setup. Perhaps the larger firebox allows room for the fine ash to blow clear, whereas with mine, the fine ash had nowhere to go.
If the coal was too "good", clinkers would not form, and I ended up shoveling fine ash out from each side [I made a 3" or so wide shovel for that purpose]. The local big vein coal does not make good stoker coal, although it usually is the best for hand firing. Some coal yards will sell small sized "nut" coal for stoker use that's made from the high quality [lower ash] big vein, but it didn't work well in the stokers.
The seams called pittsburgh, little inch and freeport worked the best for me. With the right coal, it was much less work, as there was much less fine ash, and mostly clinker. Sometimes, chunks that would not even come out of the door opening. They seem to work best with at least 6 to 8" or ash/clinker left on top of the pot. Cleaning out leaving just the fire doesn't seem to work well, until some ash/clinker builds up.
One other thing: I know of noone that monitors draft with the underfed setups here. I bet most guys are overdrafting and wasting coal. Nobody dampers the flue, and baros are never used.