HEATING BY HOT- WATER PIPES. 



177 



With the view of remedying this defect 

 so far, Mr Neeve proposed to vary the 

 length of the boiler according to the 

 length of the pipes employed ; and there- 

 fore he recommends a rectangular figure 

 rather than a square or circular one. 

 Proceeding on the well-known fact that 

 the bottom of a boiler is far superior to 

 the sides for absorbing heat, he lengthens 

 out his boiler, and, as we think, very 

 properly forms it with a slight dip at c, 

 which must have a tendency to prevent 

 the flame from passing too rapidly over 

 the bottom; the flue also passing round 

 the end and sides of the boiler, as shown 

 in transverse section, exposes nearly the 

 whole surface to the action of the fire. 



Waldroris boiler, fig. 214. — This boiler 

 is 3 feet long, 2 feet 6 inches wide, and 



Fig. 214. 



the same in depth. The fire is made in 

 the middle, and spreads around the out- 

 sides of the boiler, leaving only 6 inches 

 of water over it. The fire-place is 18 

 inches wide, and 3 feet long, which, 

 from the small quantity of water con- 

 tained in the boiler, speedily heats the 

 pipes attached to it. Not only is this 

 boiler different from most others in shape, 

 but it has another peculiarity almost its 

 own, namely, an iron box fixed to its top, 

 from which issue as many pipes as there 

 are houses or pits to heat, allowing one 

 pipe for each. Each of these pipes has a 

 stopcock at its base to turn the water off 

 or on any house, as may be required. A 

 similar box is fixed to the side of the 

 boiler near its bottom, in which all the 

 return-pipes terminate. As this boiler is 

 a close-topped one, a safety as well as 

 feeding pipe is attached to it, both for the 

 purpose of supplying it with water, and 

 also to admit of the escape of air that 

 may accumulate in it. When one house 



VOL. I. 



only is to be heated, of course the box is 

 to be dispensed with, the flow and return 

 pipes being fixed in the ordinary manner. 



p. The Scotch 



distillers' 

 boiler, (fig. 



215, ) and 

 also an- 

 other up- 

 on a some- 

 what simi- 

 lar princi- 

 ple, (fig. 



216, ) are 

 both cal- 

 culated for 

 obtaining 

 a large 

 portion of 

 fire and 

 flue sur- 

 face to a 

 small ca- 

 pacity of 

 water ; 

 they are 

 both, how- 

 ever, com- 

 plicated in 

 form, and 

 would be 

 expensive 

 if of a size 

 too large to 

 be cast in 



one piece. 

 Theyhave, 

 for the 

 most part, 

 been con- 

 structed 

 of copper. 

 Bailey's 

 boiler, fig. 



217, and 

 C o 1 1 a m 

 and Hal- 

 len's, fig. 



218, — the 

 former 

 half a hol- 

 low cylinder, and the latter a bottle-shaped 

 boiler — are both also well adapted for 

 heating rapidly, as they present a large 

 surface to the action of the fire, and con- 

 tain a limited quantity of water. Both 

 are adapted for heating greenhouses and 



z 



