Great trip report. Thanks for posting it up.
I had to check wikipedia for reverberatory before I saw that it was a furnace in your trip report. :ylsmoke:
from wikipedia:
A reverberatory furnace is a metallurgical or process furnace that isolates the material being processed from contact with the fuel, but not from contact with combustion gases. The term reverberation is used here in a generic sense of rebounding or reflecting, not in the acoustic sense of echoing.