DUCKS AND GEESE 



ence in the practice of incubator operators with re- 

 gard to cooling. No cooling should be done until 

 after the first test. After this some incubator men 

 cool the eggs by dropping the doors of the machine. 

 Others take the trays of eggs out and put them on 

 top of the machine. Cooling is usually done once a 

 day. The amount of cooling which the eggs require 

 seems to vary greatly and here again the judgment 

 of the operator comes into play. About the best gen- 

 eral rule which can be given is that the eggs should 

 be cooled until they do not feel warm to the face 

 but they should never be cooled to the extent that 

 they feel cold to the face or hands. The length 

 of time to bring this about varies with the age of the 

 eggs and the temperature of the room. 



Moisture. A good deal of moisture is used in in- 

 cubating duck eggs. It is usual to begin to spray 

 the eggs with water the next day after testing. 

 However, this may vary anywhere from the sixth to 

 the tenth day. They are sprayed quite thoroughly, 

 some men using water enough so that it runs out of 

 the bottom of the machine. No particular care is 

 taken to see that the water used is warm. Ordinary 

 water just as it comes from the pipes is commonly 

 used and is applied by means of a spray nozzle at- 

 tached to a hose. However, extremely cold water 

 should not be used for this purpose. This spraying 

 is done once or twice a day as the operator may 

 think necessary until the eggs begin to hatch. In 

 many cases even then if the ducklings seem to be 



76 



