TUBERCULOSIS 527 



seminated throughout the whole of the substance of 

 the lungs and liver, and tubercle bacilli were found 

 in these and in the peritoneal deposits. The calf 

 died of pyaemia, but sufficient time had elapsed for 

 marked local infection leading to generalised miliary 

 tuberculosis." 



We thus see that human and bovine tuberculosis 

 are one and the same disease, and that no difficulty 

 is experienced in transmitting the malady from the 

 human subject to the calf or cow, and can there be a 

 doubt as to the transmissability of the malady from 

 the calf or cow to the human subject ? 



The natural methods by which tuberculosis is 

 propagated from the human subject to the lower 

 animals are (i) inhalation of the dried expectora- 

 tion of the consumptive person, or contamination 

 by the lungs. (2) Ingestion of the expectorated 

 sputum, or contamination by the stomach, and 

 cases can be cited proving its transmission by these 

 methods in dogs, and poultry which readily pick and 

 swallow the sputum. 



We do not incline to the opinion that many of the 

 lower animals receive the infection from the human 

 subject, nor are we inclined to believe that a large per- 

 centage of the cases of human tuberculosis are trace- 

 able to contamination from eating the flesh or drinking 

 the milk of tubercular cattle. 



Tubercular deposits rarely are found in the flesh. 

 Its favourite seats are the investing membranes of 

 the chest and abdomen, and the glands, and these are 

 removed by the butcher in dressing the carcase. 

 Further, the heat to which the flesh is subjected in 

 preparing it for human consumption, is sufficient to 

 destroy the bacilli, and tuberculous beef without living 

 bacilli cannot produce tuberculosis in those who eat it. 



