PO UL TR T- CRAFT. 1 79 



WITH A HOT AIR MACHINE. Cool the eggs by leaving the doors open with the eggs 

 in the machine. Never cool below 85 degrees. Don't cool down to 85 degrees every 

 time in general to 90 or 92 degrees. * * * With the hot air machine I cool the eggs in 

 the evening; and in a room where the temperature is about 60 degrees, on the sixteenth 

 day and after, leave the door open as long as twenty minutes. Sometimes on the 

 nineteenth day I leave the door open for nearly an hour. * * The proper time to cool 

 eggs is when they are turned. In cooling a hot air machine, say for instance, twenty 

 minutes, always open the door for ten minutes before and ten minutes after turning. 



Testing Eggs see IF 239. 



259. When the Chicks are Hatching. Instructions which state that a 

 machine is to be kept closed while a hatch is in progress, are not to be under- 

 stood as meaning that under no circumstances is the door to be opened ; only 

 that the door is not to be opened unnecessarily out of mere idle curiosity. 

 Most machines have glass doors, through which the progress of the hatch may 

 be watched, and the need, if such exist, of intervention from the operator, be 

 discovered. What to do when chicks are hatching, is thus briefly and fully 

 stated by Campbell : 



" To get out the largest possible number of chicks, I wait until quite a lot of the shells 

 are pipped ; then I open the machine, and as rapidly as possible turn all the pips up, and 

 place the eggs as close to the door as possible. Those which pip in the air cell, are safe ; 

 those which pip below, very often choke at once if not turned up ; prompt turning up 

 will save most of them. If the weather is cold this turning up process is done only 

 twice ; if hot, it can be done as often as desired. Then when they begin to come out keep 

 an eye on them, and all that can turn around and break through both shell and membrane 

 will get out best if let alone. Those which turn and do not break through every time 

 they move, are very apt to smother. All such need help by simply pulling off the top 

 part of the shell to give them air, and then let them come out. This must never be done 

 until the chick is struggling to get out ; neither must the trays be pulled out. Open the 

 door and reach in, and work as quickly as possible. * * * Many operators make 

 mistakes in removing the chicks from the egg chamber. If the day is hot and close the 

 chicks will suffer very much after they become dry if too many are out at once. If they 

 are all removed in a cold day the heat will drop too suddenly for what are still to come 

 out. My rule is to remove them as soon as dry if they pant ; but if it is cold I only 

 remove a few at a time, as thej become too much crowded for comfort." 



260. Brooding Young Chicks. It is often said that hatching chicks is 

 comparatively easy ; to successfully rear them, is the difficult thing. There 

 might be less seeming foundation in fact for this statement if a larger per cent 

 of the chicks hatched artificially were really fit to live when taken from the 

 machine. There are chickens and chickens. 



The chicks are generally left in the incubators for from fifteen to twenty- 

 four hours after hatching. They are then removed to brooders, as described 

 in f 46 48. Points on feeding brooder chicks are given in ^ 146, 16 20. 



temperature of 65 degrees, the eggs, during the early stages of incubation, will lose one degree each two minutes. 

 Under an atmospheric temperature of 35 degrees, they will lose more than a degree a minute. In the latter stage of 

 incubation, when the egg has in itself a source of heat, the rate of loss is lower, and consequently the egg cools : 

 slowly in a given temperature." 



