INCUBATION 23 
chine. These pans should be kept in the 
machine until the hatch is entirely over. 
The Right Temperature. Temperature 
probably has as much to do with good hatches 
as any other single factor. If the incubator 
comes equipped with a thermometer which is 
so arranged that the bulb rests on or near the 
eggs, the machine should be adjusted to run 
at 101° the first week, 102° the second, and 
103° the third. If the thermometer used is 
arranged to hang with the bulb suspended 
perhaps one-half inch above the eggs, then 
the temperature should read 103° for the 
entire three weeks. In either case, regard- 
less of the type of thermometer used, the 
temperature should be allowed to rise to 
104° or 105° from the time the chicks pip the 
shell until the hatch is over. 
Close of the Incubator Period. If all 
the conditions previous to the hatching of 
the eggs have been correct and the tempera- 
ture of the machine has been constant, the 
hatch should be entirely over at twenty to 
twenty and one-half days. If the tempera- 
ture is allowed to drop at all during these 
Jast two days, known as the exclusion period, 
