53 2 Of Chimney Fireplaces. 



it must be brought lower, otherwise the chimney will be 

 very apt to smoke. So much has been said, in the first 

 chapter of this essay, of the advantages to be derived 

 from bringing the throat of a chimney near to the burn- 

 ing fuel, that I do not think it necessary to enlarge 

 on them in this place, taking it for granted that the 

 utility and necessity of that arrangement have already 

 been made sufficiently evident; but a few directions for 

 workmen, to show them how the breast (and conse- 

 quently the throat) of a chimney can most readily be 

 lowered, may not be superfluous. 



Where the too great height of the breast of a chimney 

 is owing to the great height of the mantle (see Fig. 13), 

 or, which is the same thing, of the opening of the fire- 

 place in front, which will commonly be found to be the 

 case, the only remedy for the evil will be to bring down 

 the mantle lower; or, rather, to make the opening of 

 the fireplace in front lower, by throwing across the top 

 of this opening, from one jamb to the other, and im- 

 mediately under the mantle, a very flat arch, a wall of 

 bricks and mortar, supported on straight bars of iron, 

 or a piece of stone (/^, Fig. 13). When this is done, 

 the slope of the old throat of the chimney, or of the 

 back side of the mantle, is to be filled up with plaster, 

 so as to form one continued flat, vertical, or upright 

 plane surface with the lower part of the wall of the canal 

 of the chimney, and a new breast is to be formed lower 

 down, care being taken to round it off properly, and 

 make it finish at the lower surface of the new wall built 

 under the mantle; which wall forms, in fact, a new mantle. 



The annexed drawing (Fig. 13), which represents the 

 section of a chimney in which the breast has been 

 lowered according to the method here described, will 



