THE INCUBATION OF THE EGG 



223 



latter will usually be readily recognized by the absence of 

 bloodvessels and a general indefiniteness of outline. 



Taking off the Hatch. — As soon as the chicks begin to pip 

 the moisture pans should be removed, unless, as is better, 

 they are so protected by a wire screen that the chicks cannot 

 get into them, and the aperture through which the chicks 

 drop down into the nursery, opened. The incubator should 

 then be closed and left closed until the hatch is well over. 

 The temperature should be carefully watched at this time, 



Fro. 109 



^., 



A handy arrangement for hardening the chickens. (Courtesy of 

 Prairie State Incubator.) 



because the heat generated by the struggling chicks is often 

 sufficient to raise the temperature beyond the limit of the 

 regulator's ability to act. It should not be allowed to run 

 above 105° F. 



After a normal run the hatch will be well over by the end of 

 the twentieth day in the case of eggs from Mediterranean 

 breeds, and the twenty-first day in the case of the American 

 breeds. With the Asiatics it frequently takes eight to 

 twelve hours longer. If the temperature runs low the hatch 



