710 
JOHN J. REPP. 
agent has easy channels of passage from the abdominal cavity 
into the thoracic cavity by way of the thoracic duct and the 
vena cava. 
Theobald Smith 63 calls attention to this migration of the 
disease, as having been observed by him and others (Spengler) 
experimentally. Even assuming the conclusions of Northrup 
and Still to be correct, although they are contrary to the opin¬ 
ions generally held, there is still left a large percentage of cases 
to be accounted for by intestinal infection. In 269 tuberculous 
children on which Still made autopsies, he considered that the 
channel of infection was the intestine in 53 cases, and the lung 
in 105 cases. This is enough to warrant the most earnest cru¬ 
sade against the source of such infection. 
However, neither animal inoculation, with its unmistakable 
results so far as the animals themselves are concerned, nor the 
recorded observations of almost doubtless transmission to man 
through the milk and meat prove, with the positiveness of a 
demonstration, that tuberculosis is transmissible to man through 
the milk and meat. Yet, to nearly all students of this subject, 
this is convincing proof, and we find the results of it in the pro¬ 
tective legislation which everywhere abounds. 
We have still further and more valuable evidence which 
may now be taken up. 
Whether or not tuberculosis of animals is transmissible to 
man, depends upon whether or not the tubercle bacillus of the 
animal species is pathogenic for man. If this could be demon¬ 
strated, we would have a positive proof that would be beyond 
all question. We know that the virulent tubercle bacillus of 
the bovine species exists in the meat and milk products of these 
animals in many cases where they are tuberculous, and we 
know that man consumes these products thus bearing the bacil¬ 
lus. Therefore, if the pathogenicity of this animal tubercle ba¬ 
cillus for the human species can be proved, the question is no 
longer debatable. The following examples are offered for con¬ 
sideration. In my opinion they are capable of supplying the 
evidence we need. 
