TRANSMISSION OF TUBERCULOSIS THROUGH MEAT AND MILK. 719 
the intestine ; primary tuberculosis of the human intestine is 
very rare ; therefore, infection of the human being with tuber¬ 
culosis by ingestion of meat and milk of tuberculous cattle is 
very rare. 
The soundness of his reasoning should be examined into. In 
the first place, as already pointed out at another place in this 
article, there is room for difference of opinion in regard to the 
prevalence of primary tuberculosis of the human intestine, and 
the burden of proof is certainly on the side of those who claim 
that primary intestinal tuberculosis is rare. I may ask on 
which side tuberculosis of the peritoneum, liver, spleen, and 
mesenteric lymphatic glands should be counted. It would 
appear most reasonable to suppose that in these manifestations of 
tuberculosis the offending bacilli entered by way of the diges¬ 
tive tube. 
Also Koch’s own experiments, detailed in his paper before 
the British Congress on Tuberculosis, in which he produced 
“ tuberculosis of the lymphatic glands of the neck, and in one 
case a few gray nodules in the lung ” of pigs by feeding human 
sputum, and “ tuberculous infiltration of the greatly enlarged 
lymphatic glands of the neck and of the mesenteric glands, and 
also extensive tuberculosis of thedungs and the spleen ” in pigs 
by feeding bovine bacilli, certainly contiadict his hypothesis, 
namely, “ that a case of tuberculosis has been caused by ali- 
menta can be assumed with certainty only when the intestine 
suffers first—that is, when a so-called primary tuberculosis of the 
intestine is found.” Pearson 82 refers to experiments of his in 
which “ it has been shown in the most unmistakable way by 
many feeding experiments .... that, contrary to the 
early belief, animals fed tubercular materials may develop 
primary pulmonary tuberculosis, and, in some instances, fail to 
show lesions in any other organ.” 
Upon this foundation Koch’s conclusion rests. I can only 
add that the facts do not warrant so sweeping a conclusion. 
After all, we must face the homely facts that we have in cattle 
and in man a very prevalent disease which we properly call by the 
