ROYAL COMMISSION ON TUBERCULOSIS 231 



Here, then, are the main facts in the evidence for both sides of 

 the question under discussion. The latter evidence tending to 

 show the transmission of tuberculosis to man by means of milk 

 and meat, is part of that upon which the Royal Commission relied 

 when it reported, "We cannot refuse to apply, and we do not 

 hesitate to apply, to the case of the human subject the evidence 

 (of transmission of the disease) thus obtained from a variety of 

 animals that differ widely in their habits of feeding — herbivora, 

 carnivora, omnivora. As regards man we must believe that any 

 person who takes tuberculous matter into the body as food incurs some 

 risk of acquiring tuberculous disease." ^ And again, " We have 

 obtained ample evidence that food derived from tuberculous 

 animals can produce tuberculosis in healthy animals. In the 

 absence of direct experiments on human subjects we infer that 

 man also can acquire tuberculosis by feeding upon materials 

 derived from tuberculous food-animals.""^ Because the tubercle 

 bacillus derived from bovine sources is, either by inoculation or 

 ingestion as food, admittedly very virulent and dangerous for such 

 diverse species of animals as the rabbit, horse, dog, pig, sheep, 

 and cow, it is highly probable that it is also dangerous to man.^ 

 For it is well known that the majority of disease-producing 

 bacteria are harmful to only one or two species of animals, but 



may be termed an " ideal " fashion, some of the very conditions essential to 

 the production of the disease in ordinary life are removed. As in men, so in 

 cattle and other animals, it may be presumed that abundance of good food 

 and fresh air, and, in general, an ideal environment, tend to counteract the 

 effect of the inoculated or communicated virus. Thus such experiments as 

 those stated above may not always fairly represent the modes of transmission 

 of the disease as they occur in ordinary life. It is not the " very healthy " 

 animal of a herd, well-housed and fed, which contracts tuberculosis. It is 

 essential to bear in mind the relationship existing between the seed (the tubercle 

 bacillus) and the soil (the tissues of man or animal). 



1 Report of Royal Commission, 1895, part i., p. 10, par. 22. 



- Ibid., p. 20, par. jj. 



^ See the researches of Villemin (1865), Klebs, Chauveau (1868), Gerlach, 

 Giinther and Harms (1870- 1873), Bollinger, and others. Further, Friedberger 

 and Frohner state in their Veterinary Pathology that Wesener compiled reports 

 up to 1884 of 369 feeding experiments, the positive and negative results of which 

 were about equal in number. From this compilation it appears that {a) 71 

 animals, among which guinea-pigs and swine proved most susceptible, were 

 experimented upon with human tubercular matter ; {b) 180 experiments were 

 made with tubercular matter from cattle ; {c) the flesh of tuberculous cattle was 

 given on 32 occasions as food, with the result that pigs were found to be more 

 susceptible than other animals, and that dogs were unaffected ; and {d) the 

 milk of tuberculous cows was given as food in 86 cases. From these experi- 



