HEATING BY HOT- WATER PIPES. 



163 



or other" of the plans offered, figs. 179 

 and 180, "where the same general prin- 

 ciples are followed as in that already 

 described ; but the boiler and furnace 

 are so formed that a smaller quantity of 

 water is contained between them com- 



pared with the surface exposed to the heat 

 from the fire, and the arrangement of the 

 parts is better calculated to promote a 

 rapid circulation of the water in the pipes. 

 For this purpose the cylinder I, fig. 179, 

 instead of being placed at the same end 



Fig. 179. 



of the boiler as the pipes, as in fig. 178, 

 is removed to the opposite end, and the 

 upper end is connected with it ; conse- 

 quently the water enters from the lower 

 pipe at one extremity of the boiler, passes 

 through its whole length over the sur- 

 faces of the furnace and flue, becoming 

 gradually heated in its passage, and then 

 rises through the cylinder into the upper 

 pipe, thus flowing in a constant and regu- 

 lar current through the whole apparatus. 

 In fig.^ 179, the front of the fire-place, 

 where ignited fuel would be inconvenient, 



is occupied with a large fire-tile 'dead 

 plate,' p, on which a supply of fuel may 

 be heated, previous to its being pushed 

 forward on the grate : q is a bridge formed 

 of fire-clay, in one piece, which may be 

 removed when the flue requires cleaning. 

 The flue, instead of passing through the 

 top of the boiler, is brought out at the 

 front, where it turns upwards, and is in- 

 tended to be carried into a common 

 chimney. Thus, the furnace and flue 

 being fixed only to the front, and uncon- 

 nected with any other part of the boiler, 



