Of Chimney Fireplaces. 569 



scheme proposed ; for if the air necessary to the combus- 

 tion of the fuel, and to the supplying of the current up 

 the chimney, be furnished by the air-tube, the warmed 

 air in the room will remain in its place ; and as this will 

 in a great measure prevent the cold currents from the 

 crevices of the door and windows, the heat in the room 

 will be the more equable, and consequently the more 

 wholesome and agreeable on that account. 



But there are, I am told, persons in this country, 

 who are so fond of seeing what is called a great roaring 

 fire, that even with its attendant inconveniences, of 

 roasting and freezing opposite sides of the body at the 

 same time, they prefer it to the genial and equable 

 warmth which a smaller fire, properly managed, may be 

 made to produce, even in an open chimney fireplace. 

 To recommend the air-tubes to persons of that descrip- 

 tion, I would tell them, that, by closing up, by means 

 of its register, the lower branch of communication (that 

 which ends just under the grate) and setting that situ- 

 ated near the top of the room wide open, they may in- 

 dulge themselves with having a very large fire in the 

 room with little heat^ and this with much less inconven- 

 ience from currents of cold air from the doors and win- 

 dows than they now experience. 



It is easy to perceive that by a proper use of the two 

 registers, together with a judicious management of the 

 fire, the air in the room may either be made hotter or 

 colder, or may be kept at any given temperature, or the 

 room may be most effectually ventilated ; and that this 

 change of air may be effected either gradually or more 

 suddenly. And here it may perhaps be the proper place 

 to observe, that in all our reasonings and speculations 

 relative to the heating of rooms by means of open chim- 



