The Essentials of Poultry Raising 



39 



house with no ventilator in the back. In this type of house the 

 air passes in at the lower part of the open front and gradually 

 diffuses back to the birds on the perch poles. The air surround- 

 ing the birds is warmer than that in the front of the building, 

 and the heated, polluted air passes upward and out of the house 

 at the upper part of the open front. 



Fig. 17. A diagram of an open-front poultry house for Southern cli- 

 mates with no ventilator in the back. This illustrates ventilation by diffu 

 sion. The air passes in at the lowest point of the open front, gradually 

 diffuses back over the birds, then passes upward as it becomes warmed 

 and finally exudes through the upper part of the open front. 



89. How to Make Houses Cool in the Summer Time. Straw 

 lofts absorb the heat from the roof and make the houses cooler, 

 The straw loft is made by tacking a two-inch mesh chicken 

 netting to the under side of the rafters and packing the four-inch 

 space thus made with straw. This 'will make the house venti- 

 lated by diffusion much cooler. It is best to provide a ventilator 



