18 



Bd. XIV. S. 264) and Bang (/Md.,Bd. 11,8. 45, 1885), no evidence 

 of great value is to be adduced. These authors, as well as Tschokke 

 (quoted by Bollinger), bring out isolated cases showing successful 

 inoculation experiments with the milk from tuberculous cows with no 

 disease of the udders, but the experiments are so few in num' er that 

 they cannot be accepted as furnishing more than a probability, and 

 extremely critical persons might be justified in ascribing the results 

 to contamination. 



Bang {Congres pour V(tude de la Tubercidose, 1, p. 70, 1888) gives 

 new results. Examining twenty-one cases of cows affected with 

 general tuberculosis but with no signs of disease in the udder, he 

 found but two whose milk showed virulent qualities upon inoculation 

 in rabbits. He concludes that since the cows experimented with were 

 in advanced stages of the disease and yet showed such slight virulent 

 properties in their milk, the danger from cows in less advanced stages 

 is much less. And this conclusion he thinks is borne out by experi- 

 ments with milk drawn from eight women affected with tuberculosis ; 

 specimens were used from all for inoculation and none were found to 

 be virulent. He draws the conclusion, thei'efore, that it is not neces- 

 sary to consider all milk dangerous coming from tuberculous cows, 

 but that it should always be suspected^ because no one can say when 

 the udder will be diseased, and because, without this, the milk from 

 tuberculous cows contains the virus in rare cases. 



I shall endeavor to show that it is not at all rare for such milk to 

 contain the virus. 



Galtier also {loc. cit., p. 81) has given the result of certain exper- 

 iments with milk coming from tuberculous cows, but he says that 

 "certain experimenters claim to have established the virulence of milk coming 

 from animals whose udders appeared to be normal and free from any lesions ; the 

 greater number, and I am one of them, liave merely encountered a virulence in milk 

 after the udder had become tuberculous. However, as a beginning tuberculosis of 

 the udder is an extremely difficult thing to recognize, especially during the life of 

 the animal, the milk should be considered dangerous which comes from any animal 

 affected, or suspected of being affected, with tuberculosis." 



I shall endeavor to show that this view of the case is justified by 

 something more than probabilities. 



In the Deutsch. Arch, far Min. Med., Bd. xliv. S. 500, Hirschberger 

 reports the results of an experimental research upon the infectious- 

 ness of the milk of tuberculous cows, in which — following out Bollin- 

 ger's work — he attempts to settle, 1st, whether the cases are rare in 

 which tuberculous cows give an infectious milk ; and 2d, whether the 

 milk is infectious only in cows with general tuberculosis, or whether 

 it is also infectious when the disease is localized. He made the trials 



