1 68 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 
opening 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 
FIG. 42. A milk pail r , . . . , 
with a special cover designed means of reducing contamination is by 
to keep out the dust which m iikm g machines. These consist of rubber 
falls into the pail during 
milking. 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 
