SOURCES OF INFECTION IK THE STABLE. 69 



are still used for milking. Such pails are, however, en- 

 tirely unfit for this purpose, since all kinds of bacteria 

 very easily lodge in them. By daily steaming, etc., it is 

 certainly possible to prevent bacterial growth from gain- 

 ing ground, but wooden vessels can hardly stand daily 

 steamings; they will soon begin to leak. In case this cum- 

 brous cleaning process is not carried on most carefully, 

 irregularities will soon appear in the milk or its products 

 pointing to a strong bacterial infection. It is therefore 

 essential to use tin pails, which -may easily be kept free 

 from dirt with its accompanying bacteria. 



Even on well-kept farms the practice of leaving the 

 milk-pails in the pasture is often met with in summer- 

 time.* Instead of bringing them home to the dairy to be 

 cleaned, they are rinsed in the pasture in some stream or 

 lake and are then turned upside down on a fence-post to 

 dry in the air. By this practice the pails are withdrawn 

 from the careful supervision which the farmer himself or 

 his superintendent may give to them when kept at the 

 farm, and the pails are not thoroughly scoured and cleaned 

 during the whole summer. In corners of milk-pails cleaned 

 in the manner given and kept in the pasture I have found 

 a slimy creamlike substance resembling coagulated milk. 

 When the substance was shown to the dairymaid she was 

 greatly surprised and could not understand how so much 

 milk could remain in the pail. By closer inspection this 

 whole whitish mass proved to be nothing but molds and 

 bacteria. They had presumably daily fed on insignificant 

 milk-remnants and strongly multiplied in the summer heat. 



* On dairy farms in northern Europe, during the summer months, 

 the cows are usually milked in the pasture or in an enclosure of the 

 same. W. 



