The Bacillus tuberculosis. 



131 



thus formed may become encapsuled by inflammatory overgrowth of 

 connective tissue, and frequently this is the case. I have seen often 

 in rabbits that the development, of tubercular disease is stopped in 

 this way for some time. Ultimately, however, the animal will succumb 

 to tuberculosis when the inflammatory process is renewed and extends 

 in the manner to be described later. 



The above statements are based upon direct observation from 

 experiments many times repeated. It is distinctly seen that one and 

 the same process, induced in both cases similarly, terminates so 

 differently in the cat and rabbit. The experiments were made under 

 exactly the same conditions, and, the animals being of the same age 

 and equally in good health, it proves clearly that the inflammation is 

 not specific, but that the animal is specific and that this lies in the above- 

 mentioned peculiar anatomy of the connective tissue of the animals in 

 question. 



Tuberculosis is an inflammatory process, as proved; it is the 

 natural and only kind of inflammation a scrofulous being can have. 

 It is also evident that for its production no special cause is required, 

 all that is necessary being direct injury to the tissue. Ordinary in- 

 flammations are caused in non-scrofulous beings by external influences, 

 such as cold, heat, etc., and nothing more than this is necessary to 

 produce tubercular disease in a scrofulous animal or individual. 



It appears from this, and from facts to be mentioned later, that 

 scrofulous animals do not become tuberculous unless an inflammation 

 is induced. No inflammation, no tuberculosis. Hence it is probable 

 that scrofulous beings do not need necessarily to become tuberculous, 

 — e. g., do not get pulmonary phthisis if they escape a bronchitis or 

 an acute pneumonia. In fact, they may escape tubercular disease 

 altogether, and die ultimately of other lesions if no injury to the 

 connective tissue occurs. The details of this research will be given in 

 a future communication. 



The results of the observations above briefly narrated suggest the 

 establishment of an anatomical criterion for the predisposition to 

 phthisis. Animals with this predisposition — viz., the described ana- 

 tomical anomaly — constitute a well-defined species, that of scrofu- 

 lous animals. The same anatomical anomaly is seen in men; and 



9* 



