Care and Management of Poultry 339 
meat breeds are persistent sitters, but clumsy, and the egg breeds 
too small, usually light, and untrustworthy. In selection of the 
individuals for brooding, choose hens that are least excitable when 
approached. A nervous hen is likely to break some of the eggs 
in the nest or to step on the little chicks when first hatched. 
Successful incubation depends, not only on the hen’s ability to 
hatch fertile eggs, but also on the nesting place and the environ- 
ment. The hen that steals her nest and sits undisturbed usually 
brings off a good brood of chicks. In setting a hen, therefore, 
the object should be to make the conditions as nearly natural as 
possible. The brooding nest should be placed where laying hens 
cannot have access to it. A dust bath, fresh water, and the proper 
kind of food should be convenient. 
The hen should be set on ‘china eggs” until she becomes 
accustomed to her new surroundings. Before she is placed on 
the nest, however, she should be thoroughly dusted with lice powder. 
When the hen becomes familiar with her nest, which will usually 
be about the second night, the real eggs may be placed under her. 
It requires approximately twenty-one days for the eggs to incubate. 
Before the chicks are hatched, provision should be made for 
the hen and her brood. When the chicks are twenty-four to 
thirty-six hours old, they may be removed from the nest and placed 
in the coops provided for them. 
544. Artificial incubation. — There are several types of ma- 
chines that hatch eggs successfully. These incubators may be 
divided into two classes: those operated by hot air and those 
using hot water. The former system is used the more extensively 
in heating incubators ranging in capacity from sixty to six hundred 
eggs, while the latter is used more for heating large machines, say 
those holding one thousand eggs or more. The most successful 
methods of supplying heat to the egg chamber are diffusion and 
radiation. 
The large incubator, one holding two hundred to six hundred 
eggs, is usually much more economical and efficient than is the 
