COOLING THE EGGS. 



Cooling the eggs, or airing them, as it is gen- 

 erally termed, is a very important part of incuba- 

 tion, and careful attention to it will be repaid by an 

 increased percentage and stronger chicks. 



"I do not need to cool the eggs," says some- 

 one, " my incubator has all the ventilation they 

 need." It may have plenty or too much ventila- 

 tion, yet for best results the eggs should be cooled 

 once a day, beginning on the second day and con- 

 tinuing to. the eighteenth, inclusive. 



The hen leaves her nest once a day, if allowed, 

 and in exceptional cases where she does not do so 

 voluntarily, she should be taken off once a day. 

 The hen that leaves and returns regularly to her 

 nest, hatches much better than the one that does 

 not. In moderate weather in the spring the hen 

 does her best hatching. She leaves her nest for a 

 limited time and returns ; the eggs do not get 

 chilled, but are properly cooled. 



In hot weather the hen is often driven from the 

 nest by lice or mites. The eggs get plenty cooling, 

 but do not hatch well. This is partly due to 

 neglect of the hen and to a lack of vitality in the 

 eggs. It cannot be all laid to too much cooling, 

 because eggs will stand considerable exposure in 

 hot weather. And it is so with eggs in the incu- 

 bator. They may be left out much longer in hot 

 weather than in the spring or winter. In early 

 spring and winter the hen sits closer ; she moves 

 the eggs from centre to outside, and they are 

 33 



