HOUSES FOR BREEDERS. 57 



before it is laid and give a tendency to the germ to die 

 sooner or later, before it has become fully developed. 



The necessity for securing a high degree of vitality in 

 the eggs intended for hatching is the more imperative 

 on account of the abnormal condition of our domestic 

 fowls as regards the great numbers of eggs they lay. If 

 the hen steals her nest, lays there twelve or fifteen eggs and 

 stops to incubate, these are invariably of high vitality. 

 By robbing nests daily, we force an unnatural number 

 of eggs. To counteract the tendency to weakness of 

 the germs, machinery is invoked, although it might 

 seem at first thought that inanimate mechanical appa- 

 ratus could have no intimate connection with vital 

 processes. 



To secure exercise in the yards for breeders, Fig. 15, 

 runways, not shown in the cut, are attached to the rear 

 of the yards. These runways are one hundred and fifty 

 feet long and two and one-half feet high, built in mov- 

 able sections. Extending across, over the tops of the 

 fences in the breeders' yards, Fig. 15, is a continuous 

 shelf, not shown in the cut, suspended over the yards 

 by wires or cords, so that it may swing freely endwise. 

 It is prevented by upright strips from swinging sidewise. 

 A section of this long shelf is represented in Fig. 17, 

 although it should be suspended by cords passing under 

 the shelf in loops, instead of passing through the shelf, 

 as in the cut. Grain is placed evenly the whole length 

 of this long shelf and a hammer is kept handy at one 

 end of the shelf. By tapping horizontally on the end, 

 the whole shelf is slightly jarred, and a very little grain 

 is dropped into each yard. At the end of the runways 

 farthest from the houses, these runways communicate 

 with another series of small yards over which is sus- 

 pended another swinging shelf supplied with grain. 



To obviate the necessity of the attendant going the 

 length of the runways to operate this distant shelf, a ham- 



