COOLING FACILITIES FOR CREAMERIES. 321 



Source of Ice. The ice for creamery use should be ob- 

 tained from as pure water as possible. A large running stream 

 is always better than a small polluted stream. Usually the 

 creamery can cooperate with butchers, restaurants, hotel- 

 men, and other local ice-users in building a dam in a suitable 

 stream. The ice can also as a rule be harvested cheaper by 

 cooperation. 



Some creameries have constructed ice-ponds near the ice- 

 house. If there is a clay or impervious bottom, this works 

 successfully and economically. The pond is filled and kept 

 filled from the creamery water-supply or from a tile drain inlet. 

 Care should be taken not to use stagnant water and water 

 in which weeds and other rubbish have been allowed to accu- 

 mulate. The pond should be deep enough so that the water 

 will not freeze to the bottom and produce dirty ice. The pond 

 should also be filled with water to overflowing when freezing 

 is begun, otherwise slush and snow are likely to accumulate 

 together with dust from the fields and roads, producing impure 

 ice. 



The ice is best when frozen from the top down. A hole is 

 bored and kept open in the ice during the freezing process. 

 Through this opening the pond is supplied with water as rapidly 

 as it subsides. When the water is solidly up against the bottom 

 of the ice it will show in the opening or hole in the ice. 



To construct an ice-pond on gravelly soil is useless, and to 

 pack such a pond with a sufficiently thick layer of clay to pre- 

 vent leakage of water is under most conditions, impracticable. 



USAGE OF ICE IN COOLING CREAM. 



1. Directly. 



2. Indirectly. 



1. The cooling of cream in creameries by putting ice directly 

 into the cream has been much practiced in the past. The 

 method is yet used considerably, especially where the old 

 open vats are still in use. Some of these open vats are jacketed 



