The Origin of Bacteria in Milk. 27 



tively answered by the assertion that the glands of a?. 

 healthy cow give off milk absolutely free from suchi 

 organisms. We call such milk sterile. Germs enter;, 

 manifestly, from the outside and may therefore be 

 termed a pollution of the milk. These decomposing 

 germs are encountered in great abundance where or- 

 ganic matter is in the act of disintegrating into its 

 composing elements, and of such decomposing matter 

 there is enough around the premises where we draw 

 milk — the stable ; there is, in fact, generally more, 

 than necessary, and this is easily brought into contact 

 with the outer cover of the milk glands — the udder_ 

 The location of the udder of oiir domestic animals, 

 involves a continual exposure to its being soiled by 

 the excrements, urine, dust from the bedding, and 

 even our most scrupulous cleanliness and precaution: 

 cannot prevent, during milking, a quantity of dirt,. 

 particles of straw and fodder, dust, hair and excoria- 

 tions from finding their way into the milk. It may,, 

 therefore, be taken for granted that the greater part 

 of dirt, and, therefore, the greatest mass of spores, is 

 derived from the udder, as well from the external 

 part of it as from the openings in the teats, and even: 

 from the interior milk cisterns. Dairymen know- 

 well that the first stoppings when commencing to> 

 milk are by no means favorable for the making of 

 cheese, and in many dairies I have found it customary 

 to milk the first few strippings into the bedding. 

 Many of the germs possess very active motion and 

 from a soiled teat find their way into the interior c£ 



