398 INFECTIVE DISEASES. 



of 1 to 2 cc. into the peritoneal cavity. Nocard injected ten to 

 twenty drops of the muscle juice of the hearts of tubercular cattle, in 

 which the disease was well marked, and none of the guinea-pigs were 

 infected. With juice of the muscles of the thigh derived from ten 

 tubercular cows Nocard inoculated forty guinea-pigs, and one only 

 showed signs of tubercle. Nocard concluded that if there was any 

 danger in the flesh of tuberculous animals, it was the exception and 

 not the rule. On the other hand, Ohauveau and Arloing produced 

 tuberculosis in two guinea-pigs out of ten inoculated with muscle 

 juice from a tubercular steer. 



In 1890 a Royal Commission was appointed to investigate this 

 subject, and the report was issued in 1895. Martin, on behalf of 

 the Commission, tested the flesh of twenty-one tubercular cows. In 

 two cases only was evidence obtained of the presence of the bacillus 

 by inoculation of guinea-pigs. The flesh of eight cows affected with 

 mild tuberculosis produced tubercle in one instance by inoculation, 

 but the ingestion experiments were negative. The flesh of five cows 

 severely affected with tubercle gave the disease in four cases, either 

 by feeding or inoculation, but only one gave the disease both ways. 

 Martin thought that some of the results were due to the butcher 

 infecting the meat in the process of dressing the carcase, either by 

 his hands or knives. Woodhead made a series of experiments to test 

 the effects of roasting and boiling on the tubercular virus in meat. 

 It was found that in boiling and roasting experiments, as ordinarily 

 carried out in the kitchen, the temperature, however high it may be 

 on the surface, seldom reaches 60° C. in the centre, except in the 

 case of joints less than about six pounds in weight. Boihng and 

 roasting were found insufficient to destroy tubercular virus enveloped 

 in rolls of meat. 



The following were among the conclusions of the Commissioners : — 



We have obtained ample evidence that food derived from tuberculous 

 animals can produce tuberculosis in healthy animals. The proportion of 

 animals contracting tuberculosis after experimental use of such food is 

 diflEerent in one and another class of animals ; both carnivora and 

 herbivora are susceptible, and the proportion is high in pigs. In the 

 absence of direct experiments on human subjects, we infer that man also 

 can acquire tuberculosis, by feeding upon materials derived from tuber- 

 culous food-animals. 



The actual amount of tuberculous disease among certain classes of 

 food-animals is so large as to afEord to man frequent occasions for 

 contracting tuberculous disease through his food. As to the proportion 

 of tuberculosis acquired by man, through his food or through other means, 

 we can form no definite opinion, but we think it probable that an 



