WASHING AND STERILIZING 311 
their high cost, which renders their use by small dairy- 
men almost prohibitive. 
Cheap Sterilizers. A cross section through a cheap 
concrete sterilizer is shown in Fig. 61. It is essentially 
a rectangular concrete tank with a wooden cover which 
is lined with zinc. The sides and bottom are five inches 
thick and are built of concrete, which is made up of one 
part cement, two parts sand, and two parts coarse gravel. 
A thin coat, consisting of one part cement and two parts 
sand, is used as an inside finish. 
Fig. 62 shows a common galvanized iron sterilizer 
which answers the purpose for small dairymen. 
Fig. 62.—A Cheap Sterilizer. 
