A brick furnace is built in the middle of the house, with the flue running through the roof.
"The Cauliflower"
A. A. Crozier
It is desirable to build in the fireplace flue a damper which can be open when the fire is burning and can be shut when it is desired to keep heat from escaping from the room via the chimney.
"A Living from the Land"
William B. Duryee
For over six weeks there was a solid block of ice in it from top to bottom, in spite of the fact that the flue was in the common wall of two living-rooms.
"The Escaping Club"
A. J. Evans