ARTIFICIAL INCUBATION 169 



What you want to tell all the time is the heat of the 

 tgg chamber. If the thermometer touches or rests on 

 an infertile e^gg it will register wrong. Never use a 

 cheap or common thermometer. If the machine you 

 use is homemade send and get the best thermometer 

 you can purchase. If you accidentally break the 

 thermometer and cannot get another, secure the best 

 you can, take it to a doctor and test it with his clinical 

 thermometer, and you can then tell how many degrees 

 it varies. I have known of complete failures in hatch- 

 ing because of the use of cheap thermometers. Even 

 tested incubator thermometers vary from one to three 

 degrees after being kept a year or two. They should 

 always be tested each season before starting the 

 machine and the temperature kept according to the 

 corrected readings. Many failures and poor hatches 

 are due solely to a thermometer which registers too 

 high or too low. 



Care of the Lamp — Be particular to fill the lamp 

 and trim it at least once a day, morning or evening, 

 but at a regular time every day. 



Turning the Eggs — The evening of the third day 

 take out the tgg tray and turn the eggs by hand. 

 There are incubators with turning machines. If you 

 have an incubator of this kind, take out the patent 

 turner. This will give you room for many more eggs. 

 Then turn them in the natural way, as the hen turns 

 them, so that they change positions once or twice a 

 day. 



Next comes cooling the eggs, which is a most 

 important and necessary thing to do. Begin on the 

 fifth day, and cool them five minutes, but not in cold 

 weather, unless the temperature of the room be above 

 sixty degrees. Eggs require less airing in cold 

 weather. Cooling makes the chicks strong and vigor- 

 ous. Start with cooling the eggs five minutes, and 



