DIRTY MILK 59 



are streptococci and other bacteria in dung and dirt that 

 may not particularly harm an adult, but may overwhelm 

 the tender intestinal tract of the infant. 



Then there are the toxic or poisonous substances which 

 are said to form in dirty milk as the result of bacterial ac- 

 tion. Although our information concerning the chemical 

 composition of these substances is incomplete, this does not 

 modify their harmful effects, if present. 



Morse sums up the general verdict of physicians who 

 make a specialty of the diseases of babies when he says 

 that "without doubt the greatest injury is done by simply 

 dirty milk in the warm season of the year; hence the high 

 infant mortality in summer." 



It is practically impossible to express mathematically the 

 danger of dirt in milk. It may be that these dangers have 

 been exaggerated. Dirty milk may not be poisonous, but 

 it is apt to be. Scrupulous cleanliness must therefore be en- 

 graven upon the standard which should ever fly from the 

 pinnacle of the dairy. 



Taking out the dirt 



All observing milkers have noticed that the foam which 

 rises on milk gradually becomes darker as the milking 

 proceeds, owing to foreign matter falling into it. A pail 

 with a small opening and protected cover keeps out a large 

 part of this dirty shower. Scrupulous cleanliness of the 

 cow and surroundings and good dairy methods are neces- 

 sary to eliminate the remaining portion. 



Dairymen try to take out the dirt invariably found in 

 ordinary milk by straining, filtering, or centrif uging. These 

 processes take out the hair, straw, particles of faeces, some 

 of the pus, blood, flies, and all sorts of gross things, but 

 not the real dirt and not the real danger. 



The milk to-day, therefore, appears to be cleaner than 

 it used to be, but appearances in this case are frequently 

 deceptive, for the milk perhaps is quite as "dirty," the 



