DOMESTIC ECONOMY OF FUEL, i 95 



The class of apparatus to be adopted in any country will vary with 

 the climate. In England the climate is of so very changeable a nature, 

 that the amount of heat required for comfort in a house varies from 

 day to day. There are many days in the middle of winter when it is 

 quite possible to sit in an unwarmed room ; or, sometimes a warm 

 morning is followed by a cold afternoon, when the sudden application 

 of heat is desirable. It is probably for this reason that in England 

 the open fireplace has, as a rule, held its own against all the proposals 

 for warming houses by means of one central fire. 



The open fireplace in ordinary use warms only by means of the 

 direct radiation of the flame into the air of the room. It is the most 

 primitive mode of warming, derived from the days when our ances- 

 tors inhabited caves. But these ancestors, by placing the fire in the 

 centre of the floor of the cave, derived from it a larger portion of heat 

 than we generally do, who place it against the wall of the room, and 

 carry off the greater part of the heat up a flue separated from the 

 room. The earlier fireplaces consisted of a large square brick opening, 

 with a chimney carried up for the escape of smoke. The large square 

 fireplace was adverse to the direct radiation into the room of the heat 

 generated, and the large chimney removed from the room a very con- 

 siderable quantity of air, which had necessarily to be replaced by cold 

 air flowing into the room through all available apertures, and this 

 created strong draughts. 



Franklin, Count Rumford, and Sylvester, are the most prominent 

 names of those who at an early period contributed improvements to 

 the warming of our houses. The main principle of fireplace construc- 

 tion advocated by Count Rumford, eighty years ago, was, that the 

 heat radiated from the fire directly into the room should be developed 

 to the utmost. He brought the back of the fireplace as prominently 

 forward as possible ; he sloped the sides so as to reflect heat into the 

 room ; he advocated the use of fire-brick backs and sides instead of 

 iron ; he reduced the size of the chimney opening, so as to prevent the 

 chimney carrying off the large quantity of warmed air it used to re- 

 move in his time. Our manufacturers of fireplaces have continued 

 in the same groove. They have, undoubtedly, in some cases, largely 

 developed the use of radiant heat. There are fireplaces, eminently 

 successful as radiators of heat, of a circular or concave form, with pol- 

 ished iron sides, the fire being placed against a fire-brick back forming 

 the apex of the concavity. So long as the concave surfaces are bright, 

 the heat thrown out by them when a clear flame is burning is very 

 great, but the gases from the flame pass directly off into the chimney 

 while they are still at a very high temperature. The heat of the flame 

 at that part will often be between 1,200 and 1,300 Fahr., and a 

 very large proportion of this heat, to the extent of at least nine-tenths 

 of that generated by the combustion of the fuel, is carried directly up 

 the chimney. 



