I moved a house that had two brick fireplaces/chimneys. Of course, they were removed before the house was moved. When I got it put back together (it was cut in half) I had to remove all the wallpaper and canvas. I found three of the flanges that bc referred to. The original occupants apparently used wood burning stoves in the adjacent room and the two bedrooms above. They heated the eight main rooms of the house with two chimneys.