The following letter has been sent out to customers of the Pet Milk Co., and will be of local interest:This is the season of the year to beware of sour milk. Many millions of dollars are lost annually due to sour and otherwise unusable milk. This loss occurs because milk is not properly handled and cooled and has to be returned, or because it will make only a low grade manufactured product that sells at a low price. Much of this loss could be avoided by a little more thought and attention.To overcome this loss we suggest that you strain the milk directly into the can through a sanitary strainer, using a cotton disc. Place the can immediately in cold water and start the cooling at once. The water should be at least as deep as the milk in the can and there should be three or four times as much water as milk.The milk should be stirred occasionally the first fifteen minutes with a clean metal stirrer. If the water warms quickly, empty and place fresh water in the cooling tank after the milk is cooled and let stand in the fresh, cold water over night. Morning milk should be cooled before mixing with night milk Where running water from a spring is available, the problem of cooling is easily solved by piping the water to the cooling tank and letting it run continuously through the tank.Unclean utensils are often a cause of sour milk. Immediately after using the milk utensils rinse them inside and outside with a cool water. Then place them in a washing vat and scrub with a brush, not a cloth, in warm water containing washing powder. Then rinse and scald with boiling water and place on a rack to dry and air.It is essential that a supply of clean, pure water be available for washing milk utensils. Wells or springs should be walled in, tightly covered, and protected from surface drainage.Help your hauler to get in early by having your milk on the milk stand when he arrives. See that he covers his truck load of milk with a canvas or blanket.