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CONTROL OF THE MILK-SUPPLY. 



the milking pail. The precaution is a simple one, costs nothing and 

 really has a surprising result in decreasing the number of bacteria 

 that get into the pail. 



Covered Milk-pail. The old fashioned pail had a flaring top, 

 the purpose of which was to make the milking as easy as possible; 

 but, incidentally, it resulted in exposing the milk to much contami- 

 nation by dirt and bacteria. Various devices for protecting the 

 milk from such exposure by the use of covered milk-pails are now 

 used. There is quite a variety among them, but they all have the 



general plan of decreasing the size of the 

 P enm g of the milk- vessels, so as to expose 

 less surface for the entrance of dirt, and 

 they also have in the opening some kind of 

 a cloth strainer for catching the larger 

 particles of dirt, thus keeping them from 

 the milk (Fig. 42). This is one of the 

 easiest, cheapest and most efficient means 

 for improving the character of the milk. 



Milking Machines. A still more recent 

 means of reducing contamination is by 

 milking machines. These consist of rubber 

 tubes ending in special cups for attachment 

 to the teats of the cow, and connected at 



the other end with large cans that can be sterilized. The cans 

 are connected with a system of vacuum tubes, and at the 

 point where the rubber tubes are attached to the can there is a 

 mechanical device by which the vacuum is made to draw the milk 

 through the tubes intermittently, thus imitating natural milking. 

 It would seem that such a plan, which carries milk directly from 

 the teat to the sterilized can, would be almost ideal, and would 

 practically remove all dirt contamination. Where these machines 

 have been intelligently used they have been found efficient in pro- 

 ducing a very clean quality of milk. But the long rubber tubes are 

 by no means easy to keep clean, and when they are used by careless 

 employees, the bacteria become very abundant inside the tubes and 

 the other parts of the somewhat complicated machine. In other 



FIG. 42. A milk pail 

 with a special cover designed 

 to keep out the dust which 

 falls into the pail during 

 milking. 



