The Bacillus tuberculosis. 



137 



The experiments on diphtheria of Prof. H. C. Wood and myself 1 ) 

 have shown that those rabbits which did not succumb to the disease 

 within a few days nearly all died of tuberculosis in the lapse of four 

 to six weeks or more. In order to see whether the diphtheritic ma- 

 terial acted specifically in the production of tubercle, or whether the 

 latter was merely the result of the inflammatory process, we experi- 

 mented by inoculating rabbits with non -tubercular and perfectly in- 

 nocuous foreign material, such as pieces of glass, metal, wood, etc. 

 The result was, in the majority of cases, cheesy, suppurating masses 

 at the seat of inoculation, followed in the course of a month or more 

 by death from tuberculosis. 



To-day, I can safely testify that Dr. Wood and myself have seen die 

 of tubercular disease proper, more than one hundred rabbits out of five 

 or six hundred operated upon, without a single one of these animals 

 having been knowingly inoculated with tubercular matter of any kind, 

 N and without any intention on our part to study tuberculosis in them. 

 All rabbits and guinea-pigs subjected to injury in any part of their 

 bodies in the various experiments, and surviving the immediate or 

 acute effects of the latter, had, with only a few exceptions, but one 

 fate, — viz., to die of tuberculosis, provided they lived long enough 

 after a traumatic interference to develop the lesion in question. 



These facts were also particularly well brought forward by the 

 results of a carefully conducted series of one hundred special experi- 

 ments on tuberculosis, executed by Dr. 0. C. Robinson, in the Patho- 

 logical Laboratory of the University of Pennsylvania 2 ). 



In non -scrofulous animals, viz., other than rabbits and guinea- 

 pigs, neither Robinson, nor Wood and myself, nor any other experi- 

 menter, ever succeded in producing tuberculosis by inoculation, unless 

 done into peritoneum or anterior chamber of the eye. No one, in- 

 cluding Koch, ever produced tuberculosis, in animals not predisposed 

 to it, by inoculation into the skin, for instance. Koch's records of his 

 own experiments prove this, and show that whenever he desired to 



*) Research on Diphtheria for the National Board of Health, 1880, Supplement 

 No. 7. See also our Reports for 1881 and 1882. 



2 ) Experimental Research on Tuberculosis. See abstract in Philadelphia Me- 

 dical Times, Vol. XII. p. 130. 



