CLEANING AND THE PROCUREMENT OF MILK 61 



the pail, as is done when using Gurler's pail (Fig. 54) ; the cloth 

 must of course be changed frequently in order to avoid the dirt 

 particles thereon being broken up and washed through by the 

 impact of the milk from the udder. 



We need not here enter into the discussion of other refinements 

 calculated to further the production of clean milk, regardless of 

 cost, which have been adppted in some other countries, for the 

 public catered for in such cases is of necessity strictly limited ; 

 the points which do immediately concern the general public are 

 the necessity for improved cowsheds and for more efficient and 

 intelligent labour for the tending of the cows and the cooling of 

 the milk. As, however, these matters also involve extra expense, 

 the only hope of progress lies in the institution of a system of 

 payment according to quality. 



The following figures illustrate the points discussed above : 



FIG. M.-Gurlers and Stadt matter's Milk Pails. (After Conn.) 



Cow dung contains over 1,000 million organisms per gram. 



Straw and earth contain up to twenty million organisms per 

 gram. 



According to Barthel^ the air in a well-kept cowshed contains 

 on an average, 300,000 organisms per cubic metre during the 

 dinner hour, and ov-er a million during the feeding of the cattle. 



According to Harrison, 20,000 organisms fall into the milking 

 pail per minute if the manure is removed and straw laid during 

 the milking, but only 1,000 if this work is done one hour before the 

 milking. 



However clean the cows and the shed may be kept, it is im- 

 possible to obtain absolutely sterile milk as the udder, even when 

 healthy, always contains some bacteria which find their way in 

 through the opening in the teats 1 . There will always be a fairly 



1 A few investigators are of the opinion that bacteria also find their way, 

 into the udder through the blood. 



