air), also enclosed by the double walls, supplied 

 by lamps through fire-proof conductors. In the 

 centre of the egg chamber and on a level with the 

 eggs is a thermostat which controls the tempera- 

 ture in the egg chamber and at the egg level. It 

 is connected by a brass rod and lever with a valve 

 on top of the hatcher, operating in such a manner 

 that just as soon as the temperature in the egg 

 chamber reaches 102 (or such degree as it may 

 be set at) the valve begins to open, turning the 



THE EUREKA BROODER. 



heat currents away from and over the heater, 

 instead of into it, and drawing cold air into the 

 heater; and when the temperature in the egg 

 chamber starts to fall below 102 it cuts off 

 the cold air and turns the currents of hot 

 air into the heat reservoir again, thus making 

 a commutual or reciprocal action between the 

 mechanism of the egg chamber and that of the 

 heater, by means of which the temperature is kept 

 85 



