62 POULTRY APPLIANCES AND HANDICRAFT 



best size. Three hatches in a season will, with average 

 success, give as many chickens as ordinarily wanted. 



Something depends on the machine, but more on 

 the operator, and most of all on the eggs. Any ma- 

 chine that will keep even heat can be made to hatch 

 successfully. If the temperature is kept at one hun- 

 dred and two or one hundred and three degrees, if 

 ventilation is reasonably good, if eggs are all of the 

 same kind of shell so that the air will enlarge at the 

 same rate, and if the air cell is watched and by ven- 

 tilation or moistening, if necessary, made to cor- 

 respond with the air-cell charts furnished with the 

 machine, the eggs having also been turned as directed, 

 then a poor hatch is almost surely the fault of the eggs. 



Early in the season eggs are less likely to be fer- 

 tile. Very late in the season many are infertile, and 

 the germs are feeble, causing many to die in the shell. 

 Eggs with thick, dark shells are harder to hatch than 

 others, and many germs die in the shell or turn out 

 feeble chicks. Eggs should be of about the same age, 

 should not be kept over two weeks before starting and 

 must all be put into machine at same time. Extremely 

 large eggs and long slender ones do not hatch well. 



Better operate the machine empty a few days at 

 beginning of each season. Fill the lamp every morning 

 and trim the wick by scraping off the top. Have a 

 new wick for every hatch and use good oil. If acci- 

 dents happen and temperature goes above one hundred 

 and five, chicks will be somewhat injured. Even one 

 hundred and ten for a few hours does not necessarily 

 kill, but most of the chicks will be weakened. Eggs 

 should be sprinkled and cooled at once after having 

 been much overheated. 



In five days from the start, test the eggs, take out 

 those that are not fertile, mark doubtful ones, putting 

 them back to be inspected ten days later. Give no 



