564 Of Chimney Fir ep faces. 



of the grate be constructed of fire-bricks instead of iron, 

 the fire will burn still brighter, and will send off consid- 

 erably more radiant heat into the room. 



I have abundant reason to think, that if, in construct- 

 ing or altering chimney fireplaces, the rules laid down in 

 my essay on that subject are strictly adhered to, chim- 

 neys so fitted up will very seldom be found either to 

 smoke, or to throw out dust into the room ; and should 

 they be found to have either of these faults, there is a 

 remedy for the evil, as effectual as it is simple and ob- 

 vious : Bring down the mantle and the throat of the chim- 

 ney lower ; and if it should be found necessary, reduce the 

 width of the opening of the fireplace in front, and diminish 

 obliquity of the covings. 



These alterations will certainly be effectual to prevent 

 either smoke or dust from coming into the room when 

 there is a fire burning in the grate ; but it sometimes hap- 

 pens, and indeed not unfrequently, that dust and soot 

 are drawn down a chimney in which there is no fire, to 

 the great annoyance of those who are in the room, and 

 to the great damage of the furniture. When this hap- 

 pens, it is commonly occasioned by a very strong 

 draught up another chimney, in which there is afire, in an 

 adjoining room ; and when that is the case, the most 

 simple remedy is to alter that other chimney, and, con- 

 structing its fireplace on good principles, to reduce its 

 throat to reasonable dimensions. But if the passage of 

 the air down a chimney in which there is no fire is occa- 

 sioned by strong eddies of wind, there is no remedy for 

 that evil but placing a chimney-pot, of a peculiar con- 

 struction, on the top of the chimney, which shall coun- 

 teract the effect of those eddies ; or by closing up the 

 throat of the chimney occasionally, by a door made for 

 that purpose of sheet-iron. 



