MILK DANGERS AND REMEDIES 133 



milking these sources had supplied the infection, 

 and the peculiar fermentation was distinctly shown 

 to be microbial in origin. So-called red and blue 

 milk, and those various hues ranging from bright 

 lemon to orange and amber, are also now known 

 to be directly attributable to bacterial activity. 



But of even greater significance than all these 

 bacterial dairy troubles is the risk of spreading 

 disease which is furnished by milk contaminated 

 with pathogenic micro-organisms. 



"There can be no shadow of doubt," said the 

 Lancet now many years ago, " that the contagia of 

 typhoid and scarlet fever are disseminated by milk, 

 and that boiled milk enjoys a much greater im- 

 munity from the chance of conveying disease." 



This was written at a time when the study of 

 bacteria was yet in its infancy, and before any 

 direct experimental evidence had been obtained 

 on the behaviour of microbes in milk or concern- 

 ing the part played by them in the dissemination of 

 disease. The writer evidently did not venture to 

 cast further aspersions on the character of milk, 

 or he might have included diphtheria amongst the 

 diseases which can be spread by its means ; but 

 there is another omission which still more con- 

 clusively indicates the remote age in the history 

 of bacterial science at which this correspondent 

 to the Lancet wrote, and that is the absence of 



