HEATING BY HOT WATER. 317 



There is another error frequently committed, in arranging 

 the route of the water. Suppose, for instance, a boiler fixed 

 at one end of a house of, say, 80 or 100 feet long, as part 

 of the work allotted to it. As in. the case of span-roofed 

 houses, it may be desirable to have three or four rows of 

 pipes all round the house. Ifow it is not uncommon to find 

 two rows called the flow-pipes taken aU round the house to 

 near the boiler, and there to start back with other two on 

 the same route into the return-opening of the boiler. This is 

 giving the water a long journey, and the return-pipes will be 

 found comparatively cold by the time the water gets to the 

 boiler. 'Now, if instead of this the whole four pipes be con- 

 nected with the flow-pipe, and go round the front and end of 

 the house nearly on a level, and start along the back down a 

 decline to the boiler, and there plunge down the drop-pipe 

 into the return-opening of the boiler, it will be found that 

 while any portion of the pipes may not be quite so hot as 

 the beginning of the two flow-pipes in the former case, there 

 wiU not be any portion of them nearly so cold as the last 

 portion of the return. I do not say that this is the best 

 way to conduct the water; but I have proved from expe- 

 rience that the arrangement indicated is the better of the 

 two named, when the pipes are, from any necessary condi- 

 tions, laid all round the house in this way. 



The supply of waste-water to the boiler and pipes is often 

 placed anywhere that looks most convenient ; but the proper 

 place is to attach the supply-cistern to the return-pipe some- 

 where near the boUer. Fixed to the flow, the water wiU be 

 frequently plunged out by the upward tendency of the hot- 

 test water. It is also very undesirable to leave the supply- 

 cistern to be kept fuU either by pouring in water from a 

 pot or by turning a tap, which is often neglected. There 

 should always be a cistern supplied by the action of a ball- 

 cock, and then the anxiety connected with the neglect of 

 supply does not exist. 



