THE INCUBATION OF HENS' EGGS 223 



Because of the tendency for a flame to "run up," as the 

 lamp and heater become warm, it is best to make a practice 

 of filling and cleaning the lamp in the morning so that if the 

 flame needs further attention it will be noticed during the 

 day and be in good working order by night. It is also a good 

 plan to do all handling of the eggs before caring for the lamp, 

 so that there will be no kerosene on the hands to be brought 

 in contact with the eggs. 



Starting the Incubator. — In starting a new incubator, or 

 one with which the operator is unfamiliar, a medium to low 

 flame should be maintained and a half-inch play given on the 

 connecting rod by loosening the thumb-nut. This will 

 allow considerable expansion at the thermostat without 

 raising the damper disk. A high ilame or too much play on 

 the connecting rod is likely to allow the temperature to run 

 high enough to ruin the thermometer. It is a safe precaution 

 to use an ordinary high registering thermometer until the 

 proper temperature has been reached, and so avoid this 

 dilHculty. Care should also be taken at the beginning of each 

 season to see that the thermometer is registering accurately. 

 It should be carefully compared with a physicians clinical 

 thermometer by moving the bulbs of both back and forth in 

 water that is 103° to 105° F in temperature. Because a 

 thermoTneter works jicrfectly one season is no criterion that 

 it will do so the next. 



When the play has been taken up and the damper raised, 

 the thumb-nut should be cautiously loosened, the amount 

 being governed by the rise in temperature necessary to bring 

 it to 101° F. on a level with the top of the eggs. When this 

 temperature is reached the flame should be so adjusted that 

 the temperature will be maintained with the damper disk 

 hanging an eighth of an inch above the heater. This allows 

 a reserve of heat for the regulator to make use of in case of 

 a drop in the incubator-room temperature. This condition 

 should be maintained for at least twenty-four hours before 

 putting in the eggs, in order to make sure that everything is in 

 good running order. The eggs should then be put in and the 

 incubator left closed for two days. 



