THE INCUBATION OF THE EGG 221 



Turning and Cooling. — After the second day the eggs should 

 be turned three times daily and cooled once. Turning may 

 easily be accomplished by shuffling the eggs gently with the 

 hands. It is a good practice to remove about two rows of 

 eggs from the front of the egg tray, roll all the eggs forward, 

 and place those removed in the back. This, in combination 

 with turning the tray a quartet of the way around each time 

 it is removed, tends to equalize any differences in temper- 

 ature there may be between different sides or corners of the 

 egg chamber. In the case of a two-tray incubator the trays 

 may be turned end for end one time and shifted from side to 

 side the next. 



The eggs should be allowed to cool until they feel cool 

 to the lips, eyeball, or other sensitive part of the body. 

 In cold weather the hands cannot be trusted to gauge the 

 temperature. 



In ordinary temperatures the time necessary for cooling 

 will vary from a few minutes at the beginning of the incu- 

 bation period to one-half to three-quarters of an hour just 

 before hatching. 



While turning or cooling the eggs the incubator door should 

 be closed to conserve both the temperature and moisture. 

 In cooling, care should be taken to place the tray square on 

 the table or top of the incubator so that part of the eggs will 

 not extend over the edge. It will be found that the eggs in 

 the portion of the tray extending beyond the edge will be 

 qhilled by the time those immediately over the table are 

 properly cool. All drafts or any means of sudden chilling 

 must be avoided. 



Both turning and cooling should be discontinued after the 

 eighteenth day. 



Ventilating. — Different styles of incubators vary so in 

 their styles of ventilation that it is difBcult to make any 

 general suggestions that will apply in all cases. It is usually 

 well to follow the manufacturer's instructions. If, however, 

 poor results that cannot be ascribed to any other cause 

 are had, means for admitting more air should be devised. 

 Few if any incubators are overventilated. 



While the hatch is coming off, ventilation should be 



