GROWING POULTRY 279 



early brooders of this type the pipes were run under a close hover, 

 and the heater used was seldom large enough to maintain the de- 

 gree of heat required in extreme cold weather. In such a brooder 

 the supply of fresh air under the hover was often inadequate, the 

 temperature was likely to run up with a high outside temperature 

 and almost certain to go down with low outside temperature, and 

 results — as was to be expected — were very uneven. The defects 

 were most serious for the youngest birds but diminished in impor- 

 tance as the birds grew, for then they not only required less heat 

 but contributed the warmth of their bodies to keep up the tempera- 

 ture through a cold spell. To provide for these conditions many 

 houses were built with individual brooders (called nursery brooders) 

 in one end, for the birds up to three or four weeks old, and a pipe 

 brooder system in the other end for the older birds. Methods of 

 reenforcing the heat furnished by the pipes were also tried. In 

 many houses two heaters had been installed to provide for the 

 contingency of accident to the heater in regular use, and in cold 

 weather both heaters were used. Supplementary coils of pipe were 

 also placed on the wall of the house, usually at the north side but 

 sometimes on the south, to keep up the temperature of the house 

 outside the hovers. All these things helped. Eventually experi- 

 menters worked out the simple plan of using a heating system of 

 sufficient capacity to maintain the required temperature under open 

 or loosely covered pipes at any season. This is the type of brooder 

 now giving the best results for artificial brooding on a large scale. 

 It is described in detail in the chapter on poultry houses. It is 

 not perfect ; even when equipped with the best-known regulators 

 at the heater and with electric regulators on the pipes, it will not 

 run reliably without close attention, but of the many different 

 methods of brooding chicks in large numbers that have been and 

 are being tried this is giving the best results of all those in 

 general use. The real test of an appliance or of a method is its 

 adaptability to ordinary conditions and to a variety of conditions of 

 location and management. Inventors of appliances and promoters 

 of methods and systems may test them under the most favorable 

 conditions, adjusting everything to suit. Under such circumstances 

 good results are often obtained with appliances or by methods 

 which in common use are not found satisfactory. 



