Octopus

In the 1880s, Henry Bowen installed a Perfect No. 3482 Warm Air Heater as the first central heating system in the house. Nicknamed an octopus furnace, it was a coal burning gravity hot air system in the basement. It operated on the principles of convection; hot air rises, cold air falls. Outside cool air entered the furnace by a wooden duct. The air was heated in a large chamber and the hot air slowly rose up to vents in the upper section of the furnace. A large metal duct was attached to each vent to carry the heated air up to a register set into the floor of the first floor of the house. The system did not use fans to move the hot air. The furnace, sometimes referred to as a spider furnace, takes its names from the appearance of the ductwork rising from the chamber.