THE FORCING GARDEN. 



545 



such as are used for conveying water through the metropohs ; 

 but, as the demand increases, pipes will be manufactured for 

 the purpose, and will consequently be improved. Thus the 

 clumsy flanger-joint will give place to a neat socket-joint, or 

 probably a better may be devised, and the pipes may be cast 

 in longer pieces, and thus require fewer of them. Some have 

 used boilers of various dimensions and forms, and have used 

 pipes of tin, earthenware, &c., which, if properly laid down, 

 answer perfectly well, but of course are much less durable. The 

 figure of both boiler and reservoir may be the same or not, 

 and may be of any shape to suit circumstances ; but that of a 

 square-sided figure will be found in most cases the best, as 

 affording greater facility in joining them to the pipes. The 

 size of both boiler, pipes, and reservoir, should be in pro- 

 portion to the size of the house and the temperature required. 

 It is ascertained that a small boiler will heat a considerable- 

 sized house ; but as the additional expense of a larger one is 

 not material, it will be better to have them in the first instance 

 sufficiently large. The form of the pipes hitherto used, has, 

 for the most part, been round ; but it is thought that square 

 ones, or shallow broad ones will answer better. Stone reser- 

 voirs have been recommended, and even stone pipes, but in 

 most cases, these would be more expensive than iron ones, 

 besides the difficulty of making them water-proof at the joints, 

 as well as of procuring stone that would not admit of the 

 escape of the water either by absorption or filtration. 



The situation in which the boiler or reservoir should be 

 placed, will depend entirely upon circumstances. In all cases, 

 both should be placed within the house, as by that means no 

 heat will be lost. The boiler may be placed in a recess in, 

 or in front of the back wall, either at the ends or middle of 

 a house, or between two houses ; the fire to be got at from 

 the back sheds ; or it may be placed in the front of the house, 

 cither in the middle or ends, as above. When the house is 

 of great length, the boiler being placed in the middle, the 

 pipes may branch from it to the right hand and also to the 

 left, and so extend to the ends of the house, and join to a 

 reservoir ; from which the returning pipe, being placed below 



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