AVIARIES, BIRD-ROOMS AND CAGES. 49 



Of all heating methods for bird-rooms, hot water 

 is undoubtedly the best, especially when the heat is 

 generated by gas under a boiler fixed outside the room, 



?c r __ 



Fig. 28. A Simple Form of Hot Water Apparatus. 



as it can then be regulated to a nicety. Fig. 28 illus- 

 trates this simple form of hot water apparatus. In fix- 

 ing pipes of this description one must be careful to get 

 them slightly higher at C than at A, because water, 

 when heated, flows to the top, cold water taking its place 

 fet the bottom, to be in turn heated itself. Therefore 

 water heated at A would flow gently to C and be pushed 

 back to A by the lower pipe, thus bringing about a free 

 circulation. Without the latter one never gets the 

 benefit of the expenditure of fuel, the heated water sim- 

 ply staying in the boiler at A. Hot water pipes, boiler, 

 and gas, we know are rather expensive, but if a fancier 

 is at all handy with tools, or has a friend who can give 

 him some assistance, this expense can be cut down. 



It will be found that if pipes are made as shown in 

 the drawing of a section at B, the heating surface is 

 almost as great as that of the ordinary round pipe, but 

 the water contained in the half pipe is, of course, only in 

 quantity half that of the other, therefore there is a clear 

 saving of half the fuel. Such pipes can be made in zinc 

 by anyone able to handle a few tools. 



As regards artificial heat for birds, in many cases it 

 is very doubtful if such is required; certainly but little 

 when a room in the house is used. Of course the 

 situation of the room ha,s something to do with it, but 

 if it is a room over the kitchen, or one attached to 

 another building, heat will only be wanted in the most 

 severe weather, which as a rule we only get a short spe 1 ! 

 of during the season. Still, it is handy and convenient 

 to have some means of taking the rawness off the air 

 when necessary. 



