"In building a house an air canal, about twelve or fifteen inches square, in the clear, and open at both ends, may be constructed, in, or near the center of each stack of chimneys; and two branches from this air canal, both furnished with registers, may open... one... into the fire-place, just under the grate, and the other over the fire-place, and near the top of the room, or just under the ceiling... The bottom of this air tube should reach to the ground, where it should communicate freely with the open air of the atmosphere..."