354 



SCIENCE OF HOME AND COMMUNITY 



to explain what is actually being done by many cities. In- 

 spectors are appointed who go into the country, examine 

 the dairies, and require the owners to meet certain con- 

 ditions of cleanliness before they are allowed to sell milk. 

 If the owners do not meet these conditions, their licenses 

 are taken away from them, or they are fined. It is vitally 

 important that no person with a contagious disease be 



connected with the dairy. 



Clean milk. The barn must 

 be clean, the cows must be 

 cleaned before each milking, 

 and the milkers must be clean. 

 As soon as drawn, the milk 

 should be put in a cool place so 

 that it will keep sweet longer. 

 It is found that the cleanliness 

 of milk can be tested by the 

 number of bacteria in it, be- 

 cause the more dirt in the 

 milk, the more bacteria get 

 in on the dirt. The numbers 

 of bacteria increase if the milk 

 is not kept cool, and they also 

 increase with the age of the 

 milk. Ordinary milk may con- 

 tain as high as 10,000,000 bac- 

 teria per cubic centimeter (about one fifth of a teaspoonful). 

 Some idea of the cleanliness of milk and the care given it 

 may be obtained by finding out the number of bacteria 

 in it. Scientists have a way of doing this. The city of 

 Rochester has set a standard of 100,000 bacteria per cubic 

 centimeter and does not allow any milk to be sold that con- 

 tains more than this. This leads the dairy men to keep 

 their barns and cows clean and to be careful in handling 

 the milk. 



FIG. 147. Sanitary milking. (Pail 

 scalded, cow groomed, milk bag 

 wiped, hands washed.) 



