BREEDING AND INCUBATION. 121 



laying class in the experimental yards are rated accord- 

 ing to their prolificness, yet the test is merely a relative 

 one, for they are not forced to profuse laying by stim- 

 ulating feed. 



SETTING THE EGGS. 



Vigor and thrift in chickens depend, in the first place, 

 upon the quality of the eggs set. Those obtained from 

 breeding stock managed as described in the preceding 

 section, will hatch strong and healthy chickens, observ- 

 ing one precaution. Care should be taken never to set 

 eggs laid near the close of the season, when the hens 

 have been very prolific, for such will produce chickens 

 deficient in vigor. The production of eggs in great 

 numbers is, in the best laying breeds, abnormal. The 

 wild jungle fowl, in common with all birds in a state of 

 nature, lays no more than she can cover, and this is true 

 of domestic hens of sitting breeds, that steal their nests. 

 It is the daily removal of the eggs by the keeper, and 

 the supply of an abundance of nutritious food, that 

 causes great prolificness. There are some species of 

 wild birds that will produce from three to ten times 

 their usual number of eggs, during a season when their 

 food is abundant, if their nests are continually robbed. 

 But when hens lay twenty or more per month, for sev- 

 eral months, the e^gs are impaired. This is one reason 

 why chickens hatched in summer are sometimes so defi- 

 cient in vigor, compared with those produced in early 

 spring. For the sake of economy it is important to 

 have as few non-impregnated eggs as possible. Over 

 ninety per cent will be impregnated if the breeding 

 cocks are strong and sprightly, and no more than ten 

 hens are allowed in a flock. It is a good plan to keep 

 two cocks for each group of breeding hens, and shut 

 them up alternately, one day at a time, in a small but 

 comfortable coop, entirely out of sight of the hens. The 



