1 76 PO UL TR T- CRAFT. 



at a true level, so that one cut will do. Then turn wick down so as to preserve its 

 smoothness while cleaning the tubes. Wipe all bits of loose charred wick off. Then 

 with a small piece of sandpaper make the burner bright. The sandpaper should be very 

 fine, so as not to scar the burner. * * * 



" Always wipe all oil from the top of the lamp. Never fill quite full. Now and then 

 lift the screen that is around the burner, and thoroughly clean all dust from it. Should 

 the light flicker, see if the screen is not filled up with dust. The dust absorbs oil from the 

 rvtck, and should the burner ever get hot enough to form gas it -will explode. * * * 



"It is a good plan to turn on a low flame at first after trimming, and in the course of 

 twenty minutes go back and see if the flame is sufficient; if not it can then be safely 

 turned to the desired point. Remember that the flame increases, instead of diminishing, 

 after being trimmed. This alone causes serious trouble sometimes, as some operators 

 when they have trimmed their lamps turn the flame on full, thus heating the burner, and 

 increasing the flame till the lamp begins to smoke, and the chimney fills with soot. As a 

 consequence the lamp goes out. * * * 



" The lamp should have flame enough at all times to keep the regulator in operation, 

 but not to excess. Keep all draft from the lamp. The flame should be steady, and 

 should never ' flick up.' " (McFetridge). 



255. Temperature. 



" The bulb of the thermometer should be placed on a fertile egg, and its temperature 

 maintained as nearly uniform as possible at 102 degrees during warm weather, and 102 1-2 

 degrees during the colder. * * * Eggs will stand considerable variation in temperature 

 before the lives of the germs are destroyed. During the earlier stages of incubation the 

 development will proceed slowly under a temperature of 98 or 99 degrees ; no more dying, 

 if as many, as when incubating at a temperature of 101 ; and if the heat is gradually 

 raised the chicks grow quite rapidly during the last stages, and are excluded on time. A 

 high temperature during earlier stages of incubation, however, is usually fatal. * * * 

 After the eleventh day a temperature of no or 112 degrees, if not too prolonged, is not 

 necessarily fatal. The greatest excess of heat can probably be withstood after the 

 sixteenth day." (Cyphers). 



" If the egg chamber is 104 or 106 degrees, which is the extreme limit without injury 

 to the embryo, taking the temperature from dead eggs, the heat of the live ones may be 

 as high as no or 112 degrees. If the temperature is taken from the eggs (which is the 

 only proper method) the heat should be either 102 or 103 degrees at the start, and never 

 exceed 105 degrees 106 being the extreme limit of safety. Eggs which have been 

 heated to no degrees may hatch out, but nine times out of ten the chicks are not worth 

 raising." (Campbell). 



"When a maker tells you his incubator is self -regulating, and will hold the correct 

 temperature, he does not mean it will do your thinking for you, predict weather changes, 

 etc. When he tells you to keep the temperature at a certain degree, you are certainly 

 making a mistake and wasting your energies if they are devoted to preventing the interior 

 of the egg chamber showing any variation from the degree mentioned. A good regulator 

 is one which maintains a proper equipoise, and if from any cause whatever the interior 

 temperature changes, it will automatically and gradually bring the temperature back to 

 the proper point without permitting it to reach a dangerous point on either side of the 

 hatching degree. A very little patience, and a knowledge of the fact that a fluctuation of 

 several degrees, (if not too long maintained), will not injure the hatch in the least, will 

 save you a great deal of annoyance on that score." (Homan). 



" If at any time before the tenth day you find the thermometer registering 101 1-2 or 

 102 degrees, say in three hours after you have attended to the machine, it is all right. 



