WASHING AND STERILIZING 



265 



labor and does very efficient work. The motive power 

 may be either steam or water. 



Sterilizing. Vessels that have been washed in the man- 

 ner described above may look perfectly clean, but may 

 still be far from being free from bacteria. These can be 

 destroyed only by exposing the vessels to the boiling 

 temperature for some time. 



Fig. 81. Cheap Arrangement for Securing Hot Water. 



The simplest method of sterilizing is to place the vessels 

 in boiling water for five minutes. This method com- 

 mends itself especially to small dairymen who have no 

 steam. 



Where no steam is available, the best means of pro- 

 curing hot water is the apparatus shown in Fig. 81. 



The hot water tank is that commonly used in residences 

 for heating water for the bath tub and can be obtained 



