PLATE XIX. 
Contains two sections; that on the right hand is the section of the plan and elevation, in the 
two preceding Plates ; shewing distinctly the arch abutting against the back wall, and the disposition 
of the flues, which are disengaged on three sides, by a particular contrivance, that as little of the 
heat may be lost in the dead work as possible; this is shewn clearly in Plate XXIII. at fig. C, 
where the apertures over the flue, through which the heated air from the cavity behind it enters the 
house, and the intervening bricks, to support the overhanging dead work, are seen. The form of 
the arch is the quadrant of an ellipsis; its thickness at the crown, the length of a single brick, the 
covering tiles and their bed not included ; the head of each of the flues is inclined a little outwards, 
that the water which shall pass through the pots, may quickly run down into the groove, seen at the 
bottom of the first step, and be by it carried out of the house. The vault is intended for a coal shed, 
and for making the fires in. 
