EQUIPMENT FOR COOLING 47 
Picture No. 1 shows a cooling tank of wood 
that is much too shallow. Night's milk in the 
upper half of the can cannot be kept cool. 
Picture No. 2 shows a cooling tank of cement. 
Even this is not high enough to bring water 
around the neck of the can. 
Open Coolers 
The campaign for instantaneous cooling has 
led to the use of open coolers. All of these are 
of tin, some of them conical in shape, and some 
corrugated, or made of horizontal pipes. They 
