Building material, ceramic building material, tile, flue tile, box flue tile
A large rectangular ceramic flue tile of single box type, almost complete and repaired from fragments. The main sides are decorated with a combed pattern and traces of mortar are still adhering.
Such hollow boxes were mainly set vertically in the walls to take hot air from the underfloor heating system (hypocaust) up the walls in order to heat the room. They are also sometimes found as parts of the underfloor system.
