202 VARIOUS METHODS OF HEATING DESCRIBED IN DETAIL. 



than a cone of cast or plate iron, with hollow sides, one hole 

 for a flow, and one for a return pipe, (these pipes can branch 

 into several directions, if necessary, on leaving the boiler,) and 

 a channel through it, with a flange, or neck, on which to fix the 

 smoke pipe ; build the boiler, thus formed, on a fire-place, with 

 just distance sufficient below the edge of the cone for a door, to 

 supply fuel ; this door should be quite narrow, in order to let 

 the edge of the boiler as far down as possible. The hot-air 

 chamber should be built of brick, and, if exposed to the atmos- 

 phere, should be at least one foot thick. In fact, the thicker 

 the wall of the hot-air chamber is made, the better will the 

 heat be retained. A tank of water is placed over the hot-air 

 entrance, inside the house, for evaporation. If this system be 

 not bungled in the construction, it will be found as cheap as 

 any other, and the expenditure for fuel is but trifling. The cir- 

 culation of the water is complete, and the air in the chamber is 

 neither roasted nor burned, as it is chiefly received through the 

 boiler, and, consequently, is possessed of more natural purity, 

 which is so essential to vegetable life ; and it requires so little 

 attention that any amateur can manage it without much trouble. 

 Even in pretty severe weather, when set fairly agoing in the 

 evening, it wants no more attention till morning ; set it right in 

 the morning, and you may safely leave it again till night. Nor 

 is it liable to accident or derangement. Not the least of its 

 recommendations is its economy of fuel, a circumstance of con- 

 siderable importance, especially where the cost of fuel is high ; 

 and, therefore, the economy thereof is of double moment to the 

 proprietor. 



We have never seen this system applied to large structures, but 

 we have no doubt, were the apparatus made in proportion to its 

 work, it would answer as well in large as in small houses ; at 

 all events, there is no reason why furnaces and boilers of every 

 description should not be chambered round in a similar way ; 

 a very great amount of heat, that is now lost, would be turned to 

 advantage, and I think it is not too much to say, that hot-houses 

 could be heated at one half the expenditure of fuel. 



The system of heating two, three, or more, houses with one 

 boiler, is one of those valuable improvements which science, 



