Incubation 



1863 



Fig. 73. — Various positions 

 of air cells 



than to permit the great increase in temperature that usually occurs 



when the chicks are coming out of the shell in greatest numbers. 



Generally, this increase may be overcome by 



turning down the lamp flame. Very often, 



toward the end of the hatching period it is 



necessary to raise the flame in order to keep 



the required temperature. These two changes 



in temperature in so short a time will be readily 



understood when it is remembered that the 



eggs supply a great amount of animal heat 



during the last week of incubation, and that 



this animal heat naturally increases as the chicks 



commence to work their way out of the sheUs. 



After the chicks are all hatched, and after they 



A .>^^*^"— -^^^ have drop- 



" ped into 



the nursery, the heat decreases. 

 There is also more or less condensa- 

 tion of moisture from the newly 

 hatched chicks at this time, and 

 this has a tendency to lower the 

 temperature. 



The position of the ventilators at 

 hatching time depends on the make 

 of the incubator. It is not considered 

 advisable to permit a very great 

 change of air imtil the chicks are all 

 out of the shell. After the hatch is 

 completed, the egg trays should be 



„ c^- r , ■ 1, , JIT . removed, together with any eggshells 



Fig. 74. — Size of the air cell at different ' ^^ / . , 



periods of incubation: i day , 7 days, 14 that may have dropped into the 

 days, and 19 days of incubation nursery, and the ventilators shoidd 



be opened to their full width. If the room is warm, the incubator 

 door may be fastened open one half inch at the top. 



The chicks should be left in the 

 nursery until the day after the hatch. 

 They should be thirty-six to forty- 

 eight hours old when they are removed 

 to the brooder. A box for transferring 

 chicks to the brooder is shown in 

 Fig. 75. If a market basket is used it should be lined with burlap, and a 

 burlap blanket should be placed over the chicks. 



Fig. 75. — A serviceable box for moving 

 chicks from the incubator to the brooder 



