XVI 



years been privileged to hold a Sanitary Kesearch Scholarship to 

 the Honourable Grocers' Company, he avails himself very fully 

 of the knowledge gained by all the most prominent scientists in 

 the course of their bacteriological investigations, and combines 

 this with the results of his own researches. Eeferring to a series 

 ■ of experiments reported by Klein in 1886, by which it was 

 found that the activity and power of growth of bacilli might be 

 modified outside the body by variations of temperature — a dis- 

 covery, by the way, which had already been made by Pasteur — 

 and possibly also by introducing them into animals " whose 

 normal temperatures and other general metabolic conditions are 

 different," he pomts out that "it has been proved experimentally 

 that, although the organisms in human and bovine tuberculosis 

 are morphologically identical, they are not absolutely the same 

 in all their vital and pathogenic characteristics." The inocu- 

 lation of a cow with human tubercle bacilli causes acute general 

 tuberculosis, but where the inoculation is from the cow to the 

 human subject, this " almost invariably gives rise to the 

 perhucht form of tuberculous disease, and rarely, or never, to the 

 acute generalised form." Here, then, we have evidence of a 

 close similiarity without absolute identity, and the difference is 

 one which, as George Stephenson might have put it, is " bad for 

 the coo!" There is, however, a possibility of infection by 

 ingestion from the consumption of tuberculous meat ; but this, 

 I may say without referring particularly to the evidence which 

 can be adduced, has been greatly exaggerated by local writers. 

 The risk of infection being conveyed by the agency of milk from 

 tuberculous cows is more real, but even in this there seems to 

 have been abundant exaggeration. 



I will now turn to the other side of the subject and briefly 

 allude to the natural methods by which the human subject is 

 protected against dangers which, without such wonderful pro- 

 visions against the contraction of the disease, would be most 

 formidable — "A perfectly healthy individual, placed under 

 favourable conditions as regards food, fresh air, and exercise is 

 never attacked successfully by tubercle bacilli, the active vigorous 

 tissue cells being perfectly competent to destroy any bacilli that 

 may make their way into the lungs, the pharynx, or the 

 intestine ; whilst even in cases of direct inoculation into a 



