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POTJXTRY CULTURE 



An incubator consists of three essential parts— namely, an 

 insulated and ventilated box— the body— a heater, and a regu- 

 lating device. 



The body of the machine is supported by legs. The heating 

 device is attached to the side of the body, except in those oper- 

 ated by electricity or by a stove. 



The body is provided with three chambers— namely, an 

 upper, middle, and a lower (Fig. 153). 



The upper chamber is the heating chamber, and is separated 

 from the egg chamber by a diaphragm in those heated by 

 diffusion or by a radiating surface in those heated by radiation. 



Fig. 154. — A view showing insulation of a small incubator. 



The diaphragm is usually of cheese cloth. After each hatch 

 this cloth should be thoroughly dusted to keep the pores of the 

 cloth open. 



In single-tray incubators, the tray should be turned end for 

 end. In two-tray incubators the trays should be turned end 

 for end and trays exchanged each day. 



In the hot-water system the chamber is occupied by pipes. 

 These pipes are not separated from the egg chamber. 



The eggs occupy the middle or egg chamber. 



The lower chamber is provided with a canvas-covered tray, 

 and is called a nursery chamber. A glass door is placed before 



