20 BULLETIN 890, U. S. DEPARTMENT OF AGRICULTURE. 
Fig. 11. — In-the-bottle pasteurizer, showing pumps which force the 
over the bottles. 
sprays of hot water 
have the cooler considerably longer than it is high, so that the avail- 
able elevation will allow gravity flow of the milk. Table 7 shows 
the methods of cooling used at various plants. Sometimes coolers 
are made in three sections, water being used in two of them and 
brine or direct expansion in the third. In this way better use of 
the water is made. At one plant the temperature of the milk from 
the first water section was 78° F., from the second 64° F., and from 
the brine coil 34° F. The second section cooled the milk from 78° 
to 64° F., thus saving considerable refrigeration. (See fig. 8 for 
internal cooler.) 
IN-THE-BOTTLE PASTEURIZATION. 
With the " in-the-bottle " system of pasteurizing, which has been 
developed within recent years, the milk is pasteurized after it has 
been put into the bottles. The bottles of milk, in cases, are placed 
in a compartment and heated to the desired temperature, held, and 
cooled. With some types the milk is heated, held, and cooled in the 
same compartment, while in others the bottles, after being removed 
from the cases, pass slowly through the machine, being heated at 
the beginning and cooled at the end of the process. With this system 
it takes 30 minutes for the bottles to travel from the point where they 
