The Machine as a Mother. 



35 



of the chick, but induces rapid growth of the embryo, until 

 it is too large to remain in the egg and too young to 

 emerge, the result being that it dies in the shell. In this 

 connection it may be stated that as good results have been 

 obtained in incubators that allowed no flow of air, and in 

 which no moisture was allowed, as in the reverse conditions 

 the air being motionless, not requiring saturation. When 

 chicks come out of the eggs they provide a large amount of 

 moisture themselves, and are then subject to being chilled 

 from rapid evaporation in the warm dry air and warm moist- 

 ure ; the consequence being that a hen, when her chicks are 

 coming out, will sit more closely on the nest than at any other 

 time, and will resist any attempt at disturbance just at that 

 period; a fact which is a strong protest against opening the in- 

 cubator to remove the chicks until all are hatched and dried, 

 as there will then be a sudden fall of temperature, due to the 

 removal of the sources of animal heat, which is often fatal 

 to the chicks yet unhatched. 



Having referred to the hen by way of illustrating some 

 thing that may be required with the incubator, a few con- 

 densed rules will probably be of value to the inexperienced : 



1. An incubator can be more easily operated in a room of 

 even temperature, and it should never be placed near a win- 

 dow, as that side nearest the window will be cooler than the 

 side away from it. 



2. Place your eggs in the trays or drawers, and then cull out 

 all that are extra large, small or rough, and fill the spaces 

 with more perfect eggs. 



3. Keep the temperature at 103 degrees. Do not cool the 

 eggs. Turn them twice a day. 



4. The cause of chicks d>ing in the shells may be due to 

 too much moisture, too high temperature, too low tempera- 

 ture, lack of constitutional vigor of parents, too frequent 

 opening of the incubator, or to the fact that the eggs are from 

 hens that are overfed and fat. 



5. When the chicks do not hatch out until the time is past, 



