BEOODING 453 



of the sun's rays in destroying harmful bacteria not of soil's 

 bacteria group. 



Each hover usually has a capacity of from fifty to seventy- 

 five chicks. 



Hovers are of different types. The two general types are 

 the stationary and adjustable. The heat is conveyed lay water 

 in iron pipes in a box close to the floor and the pipes warm the 

 air. Warmed air rises, and the chicks are always assured of a 



Fig. 180. — The interior of a oommoroial brooder house, showing compart- 

 ments and runs. 



gentle, ever-changing, pure warm air. Three grades of heat 

 are thus ensured — first, it is warmest under the hover, cooler 

 between the hover and the partition, and cooler in the chick 

 pens. Thus the chick is aUowed to get into the temperature 

 best suited to him. The felt on the hover is slitted and the 

 chick can readily go in and out. 



Having a small unit hover system chicks of different ages 

 can be raised, as each size chicks must be kept by themselves. 



It is estimated that a 20-hover system house will need a 

 floor space of 14 by 66 feet. 



