TUBERCULOSIS. 397 



appeared to have invaded the body by the intestinal canal. These 

 facts, taken in connection with the occasional existence of tubercle 

 bacilli in milk, went far to prove, in his opinion, that milk was a 

 source of tubercular infection, especially to young children. 



From his own experiments and observations the author has 

 drawn the following conclusions : 



1. Cows with tuberculosis of the udder are to be found in dairies 



in this country. 



2. The milk of these cows is, as a rule, mixed with the general 



supply. 



3. The milk in cases of udder tuberculosis contains tubercle 



bacilli. 



4. Rabbits inoculated with, or fed upon, milk containing tubercle 



bacilli contract tuberculosis. 



5. Direct evidence of transmission of tuberculosis by milk to man is 



wanting, but from the effect of such milk on the lower animals 

 it is reasonable to conclude, in the present state of our know- 

 ledge, that there may be danger in using the milk of cows 

 with tubercular udders, and therefore strict inspection of 

 dairies should be enforced ; and boiling of milk before 

 use will, as a rule, be a wise, if not absolutely a necessary 

 precaution. 



Bollinger has shown that the virulence of cow's milk is reduced 

 by dilution with water in the proportion of 1 in 40 and even of 

 1 in 100, and that therefore there would be much less danger 

 in consuming tubercular milk which had been mixed with the 

 milk of healthy cows, than there would be in taking it direct 

 from the infected cow. This is a matter of scientific interest ; but 

 it would be no justification for a dairyman to mix the milk of a 

 tubercular cow with milk of cows known to be healthy. The milk 

 of cows suffering from tuberculosis should undoubtedly be rejected. 



TUBERCULOSIS AND THE PUBLIC MEAT SUPPLY. 



The question of the advisability of allowing the flesh of tuber- 

 cular animals to be sold for food, especially when the disease exists 

 in a very small degree, is a vexed one. Numerous experiments 

 have been made upon the infectivity of the flesh of tubercular 

 animals. Kastner inoculated the juice expressed from the flash of 

 tubercular cows. Sixteen guinea-pigs were unaffected after injection 



