42 Of the Management of Fire 



The closed fire-places which I have recommended, 

 and which will hereafter be more particularly described, 

 will answer this purpose completely. The fire being 

 closed in these fire-places on every side, as well below 

 the grate as laterally, and in short everywhere, except 

 where the bottom of the boiler presents itself to the 

 fire, none of these rays can possibly escape ; and as the 

 materials of which the fire-place is constructed (bricks 

 and mortar) are bad conductors of heat, but a small 

 part of the heat generated in the combustion of the fuel 

 will be absorbed and transmitted by them into the inte- 

 rior parts of the wall, there to be dispersed and lost. 

 But the confining of heat is a matter of sufficient 

 importance to deserve being treated in a separate 

 chapter. 



CHAPTER III. 



Of the Means of CONFINING HEAT, and DIRECTING ITS 

 OPERATIONS. Of Conductors and Non-conductors 

 of Heat. Common Atmospheric Air a good Non- 

 conductor of Heat, and may be employed with great 

 Advantage for confining it ; is employed by Nature 

 for that Purpose, in many Instances ; is the princi- 

 pal Cause of the Warmth of Natural and Artificial 

 Clothing; is the sole Cause of the Warmth of Double 

 Windows. Great Utility of Double Windows 

 and Double Walls: they are equally useful in Hot 

 Countries as in Cold. ALL ELASTIC FLUIDS Non- 

 conductors of Heat. STEAM proved by Experiment 



