ACCESSORIES AND APPLIANCES 
A hygrometer is a 
very useful instrument 
used for measuring the moisture in the 
incubator, and it costs about twice as 
much as a thermometer. 
A good way to run an incubator with- 
out one is to set a hen at the same time 
you do your incubator. Her nest should 
have plenty of damp soil under it. Watch 
the air space in the large end of the eggs, 
that are under the hen, grow large as the 
incubation proceeds. If the air space in 
the eggs in the incubator grows as fast as 
those under the hen, your moisture is all 
right. It is a good plan to put under your 
trays as many pans of water as there is 
room for at the beginning of the hatch, 
and if the air space in the eggs in the 
incubator does not grow as fast as those 
under the hen, you can remove some of 
them. Never remove the two that are 
over the holes in the bottom of the ma- 
chine, and always keep water in them. 
The eggs should be 
turned twice each day 
after the second day until 
the eighteenth day. They should also cool 
and air each day for a short time. Place 
121 
Moisture 
Turning the 
Eggs 
