FORCING DEPARTMENT. 320 



In the setting of the boiler, &c. much depends on 

 the rapidity of heating the water, as when the fire 

 that plies under and around the boiler has not a 

 proper draft, a considerable time must elapse before 

 the water in the reservoir, at the extremity of the 

 house, is warmed. The boiler, reservoir, and pipes, 

 should be always, when practicable, as near on a 

 level as possible, which will cause the hot water 

 water to flow more rapidly to the extremity of the 

 house into the reservoir, whence it returns through 

 the lower pipe into the bottom of the boiler, where 

 it again becomes heated ; and the hottest particles, 

 being the lightest, ascend to the surface, and are pro- 

 pelled along the upper pipe, forcing the colder ele- 

 ment before the warmer body into the lower pipe, 

 and so again into the bottom of the boiler. Thus 

 the circulation is continued while there is any fire 

 under the boiler ; and the heat remaining in the 

 brick work after the fire is burned out, will be suffi- 

 cient to retain the heat in the boiler, pipes, &c. for 

 many hours. 



The Plate, No. 20, will illustrate the principle 

 on which the boilers, pipes, and reservoirs, are 

 erected. The boiler (A,) is placed in a niche of 

 the back wall, and can be attended to from the 

 sheds behind, where the fire is supplied to it. 

 The pipes (C,) that proceed horizontally from the 

 boiler to the front of the house, are circular, and of 

 four inches diameter ; the upper one enters the 

 boiler within two inches of the top, and the lower 

 about two from the bottom. These pipes are con- 

 2 u 



