ANIMAL HEAT. 



Animal heat during incubation is not noticeable 

 until about the tenth day, though a fresh, strongly 

 fertilized egg, having been subjected to a tempera- 

 ture of 103 for thirty-six hours, and then broken 

 in a saucer, will reveal a live, pulsating heart, the 

 beats of which may be counted, and it will make 

 about sixty before it stops or dies. 



As the animal heat increases less artificial heat 

 is required to keep up the proper temperature in 

 the egg chamber. On this account it is generally 

 necessary to occasionally adjust the regulator a 

 little the last week of incubation ; but the lamp 

 flame or flames should be gradually (a little at a 

 time) lowered if it appears that you are using more 

 flame than is necessary to supply just a little sur- 

 plus heat. 



Although it does not require as much artificial 

 heat during the latter part of the hatch to keep up 

 the right temperature, it should be distinctly under- 

 stood, that the temperature must be kept up just 

 the same as at the first part until every hatchable 

 egg is hatched. [See When Hatching.] 



WHEN HATCHING. 



When the chicks are breaking and coming out 

 of the shells, remember that the doors of the incu- 

 bator should not be opened but twice in a day, to 

 take out chicks that have hatched and are dry. 



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