HEATING ROOMS BY STEAM. 333 



mcmorlaUst is able to judge, there seems to be little or no History andac^ 

 danger of fire from a stove of this construction. The^^^J^^^^ J^,'^^^ 

 greatest inconvenience of a common stove is, that the ing rooms by 

 cockle or raetal furnace is liable to crack from the inten-^^^^™' 

 sity of the heat. By the continuity of the metal from the 

 fire-place, an intense heat is also conducted along the 

 pipes, which exposes them to the same accident. Here 

 the smoke being previously conveyed through a brick flue, 

 can never communicate to the pipes a degree of heat suf. 

 ficient to crack them. In like manner the pipes, having 

 no communication with the rooms but by the small aper- 

 tures, cannot come in contact with any combustible sub- 

 stance; and from being surrounded with air, which is con- 

 stantly changing, can impart only a very moderate degree 

 of heat to the walls. The iron supporters of the pipes may 

 be imbedded in some substance which is a bad conductor 

 of heat, as furnace ashes and lime, &c. The emission of 

 heated air into the rooms may be regulated hy valves. As 

 the pipes are not exposed to cracking, there is no risk of 

 their throwing smoke or vapour into the rooms. 



The boiler b, b, is six feet long, three and a half broad, 

 and three feet deep. As there is nothing peculiar in the 

 feeding apparatus, it is omitted. The boiler m.ay be placed 

 in any convenient situation. Where a steam engine is use^ 

 for other purposes, the steam may be taken m its boiler.- 

 The pipe c, c, conveys the steam from the boiler to the first 

 perpendicular pipe d, d, d. There is art expanding joint 

 at e, stufied, to make it steam tight. The steam ascend- 

 ing in the first pipe f/, d. d, enters the horizontal pipe/,/,/,/, 

 (which is slightly inclined) expelling the air, which partly 

 escapes by the valve ^5 and is partly forced into the other 

 pipes. The valve g being considerably loaded, foices the 

 accumulating steam down into the rest of the pipes rf, d, d. 

 The air in these pipes recedes before the steam, and is forced 

 through the tubes h, A, A, into the pipe m, m, m, whence it 

 escapes at the valve i, and the syphon A;. The water, con- 

 densed in the whole of the pipes, passes also through the 

 ;tubes h, h, h, A, into the pipe m, wj, tw, which has such 

 a declivity as to discharge the water at the syphon k\ into 

 ihe hot well «, whence it is pumped back into the hollm: 



The 



