WHOLESALE BREEDING 69 



glass with a mixture of white lead and gasoline. The principal one is 

 to coat glass on the outside with a mixture of white lead and gasoline. 



The chief objection to the long-narrow type house with opaque 

 roof is that it is not compact and multiplies walking steps. A suc- 

 cessful modification in nearly square form has been worked out, in 

 which enough light is secured in the centre of the building by a series 

 of skylights in the roof, comprising about one-quarter of the roof area. 



When the windows or sashes are open they should be fitted with 

 inside screens of J^4-inch mesh to keep out insect enemies, but admit 

 gnats and other forms of insects, which, together with their larvce, 

 form an important item of fishfood. 



The most satisfactory form of heating is with the hot-water sys- 

 tem, this being much more flexible than steam, and cheaper to operate. 

 Modern invention has produced automatic heat-control devices which 

 can be installed at moderate cost. These are extremely valuable in 

 guarding against the dangers of sudden cold spells at night, particu- 

 larly where tropical fishes are kept or when young goldfishes have 

 been hatched in the late winter or early spring months. Oil stoves 

 are not to be recommended and should only be used in emergencies. 

 The carbonic product of combustion while small in quantity is, never- 

 theless, injurious. Water absorbs most gases very freely. 



The cement floors of fish houses should be provided with gutters 

 next to the tanks, these all draining to a single point so that the floors 

 can easily be flushed. 



A description of methods of building concrete ponds and tanks 

 will be found on page 219. 



WINTERING GOLDFISHES 



As the thermometer drops towards SO it is time planning to bring 

 the fishes indoors. By leaving them out till really cold weather sets 

 in they are at first stimulated by the indoor heat and then become 

 droopy. A little freshening of the water from time to time is advis- 

 able until they become used to indoor life. 



If one has insufficient aquarium or indoor pool space to keep the 

 stock of fine fishes over winter, tubs will be found good, especially 

 those of papier mache, or of old wood. 



Fishes do well over winter in tubs in cellars at a temperature 

 between 50 and 60 degrees. The dim light from a window is suf- 

 ficient. Allow plenty of air surface per fish and use no plants. The 

 water may be quite shallow — about 4 to 6 inches. Occasional par- 

 tial changes of water Vvdll prove beneficial, particularly in concrete 

 tanks. 



