140 The Hen at Work 



ventilated, it may be assumed that the air thus 

 supplied, and the brief period of airing when the 

 eggs are sprinkled, will bring results which are fully- 

 equal to those gained by the process bi cooling 

 the eggs each day. 



If the eggs are cooled, remember that the life 

 developing within grows more sensitive to low 

 temperature as the incubation goes forward after 

 the twelfth day. Great care should be taken 

 during the last few days to keep the eggs from a 

 chiU, as a temperature of fifty degrees, which they 

 would stand very well for several hours, about the 

 tenth day, would be fatal during the last week of 

 the hatch. 



Turning the Eggs. — Some interesting experi- 

 ments have been made to discover what effect will 

 be made on incubation by turning the eggs. In 

 one of the first tests three machines were used 

 with twenty-five eggs in each. In one machine 

 the eggs were turned five times daily; in another 

 twice daily, and in the third they were left unturned. 

 In the first machine, fifty-eight per cent, hatched; 

 in the second foity-five per cent, hatched; in the 

 third only fifteen per cent, of the unturned eggs 

 produced, live chicks. 



