down ashes are a ergonal conductor
ventilation_shaft is inert_artifact. excavation_pit is inert_artifact. elevator_shaft is air_path_through_solid. going_down is change_of_location. downspin is downturn. hull_down_fighting_position is hexalateral_object. downcast is shaft. going_down is going_down. descending_stairs is going_down. going_down is movement_along_surface.