Question: Provide another name for a structure that provides ventilation for hot flue gases, or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere, used in relation to boats rather than buildings, an example being the paddlewheel steamboat known as the Lexington which sank due to an onboard fire when the structure caught fire igniting 150 bales of cotton?
Sentence (from "Fly ash"): Fly ash, also known as "pulverised fuel ash" in the United Kingdom, is a coal combustion product composed of fine particles that are driven out of the boiler with the flue gases.
Relevant evidence: No