THE MAMMOTH INCUBATOR AND BROODER 



429 



arrows. In the compartment will be noted the thermostat or 

 thermoregulator, just above the eggs (/). Its connection with 

 the compartment valve is easily traced. In Fig. 160 g and h 

 shows these valves in two operating positions. When the 

 thermostat opens the valve wide there is a free flow of heated 

 water into the pipes, and when the compartment becomes too 

 warm it gradually closes down, thus gradually regulating the 

 amount of water that passes into the pipes and thus maintains 

 an even temperature. Other types do not regulate the cham- 

 bers by a hot-water valve, but instead provide a thermo- 

 regulator, as shown on the smaller type machine (Fig. 156), 



Fig. 162. — The parts ot a heater in a giant incubator: a, The base and 

 grate; 6, the brick ring; c, heater, water-pot, and top; d, pipe tanic and gauge- 

 glass. 



which, as the chamber becomes too warm, opens up a circular 

 opening at the top of the chamber and allows the escape of the 

 surplus heat. 



The mammoth incubator has trays opening on both sides, 

 thus giving right- and left-hand compartments. 



It will be noted that while all of the compartments in Figs. 

 159 and 160 are connected with the main water-supply, because 

 of the compartment valves there are two water circulations. 

 First, there is a continuous circulation in the main supply, and, 

 second, an intermittent circulation in each compartment radia- 

 tor for each sitting of eggs. 



The first circulation is in the water-jacket around the heater 

 fire (Fig. 159, b), from which the hot water flows through the 

 right hand in (Fig. 160) a large covered pipe, carrying the heat- 



