PLATE XXIII. 
centre. The furnace should never project beyond the back wall in any of the degrees, shewn in the 
sections of Plates I, II, III, &c. unless there is a sufficiency of dead work above them, (as in section 
of Plate V.) to prevent the heat escaping. 
At G, is shewn the dipping flue of Plate V. at large, which many think impracticable ; but a little 
acquaintance with pneumatics will convince them of the contrary. 
At H, the damper referred to in Plate VIII. is shewn in a part of the funnel or chimney; it should 
be placed on the outside, as high as a man can reach with ease, and should slide in an iron frame ; 
according as this is opened or closed, after the cold heavy smoke is passed, more or less heat will be 
thrown into the house. 
