THE PASTEURIZATION OF MILK 



which extend through the milk to the top of the 

 tanks. Any loosening of these valves, or any in- 

 accurate adjustment of the cams which operate 

 them, may cause milk to be discharged from a tank 

 before it has been held a proper length of time. 

 The efficiency of the apparatus would thus be 

 impaired. 



The fact that the temperature of the heated 

 milk is not reduced during the holding process 

 appears to be an advantage. The surrounding 

 jacket of hot water maintains or increases the 

 temperature of the milk in the vats. 



In Fig. 22 the eight tanks are arranged in a 

 circle upon a frame or platform, which itself re- 

 volves, carrying the tanks with it. A central tank, 

 which is stationary, receives the milk from the 

 heater. From this tank the milk is distributed to 

 the various holding tanks by means of pipes, 

 which radiate from a central valve beneath the re- 

 ceiving tank. This single central valve is of very 

 ingenious construction, and is so made that all the 

 holding tanks are filled and are also discharged 

 through the same valve. Thus it is seen that this 

 one valve replaces the sixteen valves which are 

 employed in such an apparatus as shown in Fig. 

 100 



