Contamination of Milk, 29 



with a small opening is desirable. The larger part of 

 the dirt entering the pail comes from the flank rather 

 than from the udder. The dirt is dislodged by the eon- 

 tact between the milker and the flank of the animal. 

 All this material finds its way into the common large 

 topped pail. If the opening is restricted to six inches, 

 the exposed surface is greatly lessened. A six inch 

 opening is one-fourth as large in area as a twelve inch. 

 The reduction of contamination will be in still greater 

 proportion as with the small topped pail the opening 

 is directly beneath the udder during the milking. The 

 dirt from the flanks does not find its way so readily 

 into this pail as it does into the ordinary pail. 



Stocking has shown that under ordinary barn condi- 

 tions the number of bacteria found in milk drawn into 

 such a covered pail was but five per cent of the number 

 found when an ordinary pail was used, and with very 

 dirty cows but 3 per cent. 



Many forms of pails of this character have been sug- 

 gested. All seek to reduce the size of the opening in 

 one way or another. Some of the most practical forms 

 are represented in Figs. 8 and 9. In some of the pails, 

 strainers of cloth or cotton are used, although brass 

 wire gauze is effective and easier cleaned. 



The use of the milking machine avoids a large part of 

 the contamination from the animal since the milk 

 is drawn directly into a closed tube through which it 

 passes to the receiving can. 



Contamination from utensils. The various utensils 

 used in handling milk always contain bacteria, the 

 number depending on the cleanliness of the utensnX 

 which is determined (1) by the manner of washing, (2) 

 the construction of the utensil, (3) the condition of the 



