1390 The Cornell Reading-Courses 



the wick down slightly, and cut away the burned part. If scissors are 

 used, they should be placed flat on the wick tube and the wick cut straight 

 across, the burned part being severed at a stroke. Practically the same 

 result may be obtained by drawing a burned match across the wick tube. 



Cleaning the burner. — Before cleaning the wick tube, the wick should 

 be turned down in order that it may not be disturbed and the flame thus 

 be made irregular. All the black material should be removed by sand- 

 paper, a knife, or some other sharp instrument, and the tube should be 

 wiped with a cloth. Care should be taken not to bend the wick tube, as 

 such bending will prevent the wick from working freely. The other parts 

 of the burner should be well cleaned. The screen around the wick tube 

 should be cleaned once a week, and the burner should be boiled at least 

 once a season in hot water containing washing powder. 



Regulating the flame. — A new wick or one that is newly trimmed should 

 be watched at first to prevent the flame from running up and smoking. 

 The flame should be maintained sufficiently high to keep the temperature 

 at the proper degree and the disc raised slightly during the day. In case 

 the room temperature drops at night, the surplus heat will be used to 

 prevent a drop in temperature in the egg chamber. If the flame flickers, 

 the operator should look for a broken isinglass in the heater and should 

 see that the burner is in place and is working properly. 



Regulating the heat. — The heat is regulated by turning the adjustment 

 nut above the regulator bar on the connecting rod. By screwing up on 

 the adjustment nut until the disc over the heater drops flat on the heater 

 exhaust, all the heat will pass into the machine and the temperature will 

 be increased. By screwing down on the adjustment nut and thus raising 

 the disc, the heat will be allowed to escape. When the proper temperature 

 has been reached, the thumbscrew should be turned until the disc is about 

 one eighth of an inch above the heater. When once correctly regulated, 

 the temperature will vary only slightly if proper care is given to the lamp 

 flame. Outside temperattire changes should be met by altering the lamp 

 flame and not the regulator; as the chickens develop, however, more heat 

 will be given off from the eggs, and the resulting increase in temperature 

 will necessitate changing the regulator. The eggs should never be placed in 

 the incubator until the temperature is properly regulated. 



TEMPERATURE, MOISTURE, AND VENTILATION 



Temperature. — After the eggs have been placed in the machine, the 

 temperature will drop and remain low for some time ; it will then gradually 

 rise, taking perhaps twelve to fourteen hours to reach the desired degree. 

 The operator should not attempt to run the heat up too rapidly, but should 

 allow this gradual increase. When the correct degree is reached, the 



