218 MICRO-ORGANISMS AND DISEASE. [CHAP. 



Another gentleman working in the laboratory of the Brown 

 Institution intended to inoculate several guinea-pigs with 

 human tubercles. For this end he mashed up in saline solu- 

 tion, in a clean mortar, a bit of human lung studded with 

 tubercles. He did this in my room on the same table on 

 which I was working with anthrax. One of these guinea- 

 pigs, inoculated with human tubercle, died before the second 

 day was over of typical anthrax. Its blood was teeming with 

 the bacillus anthracis. Such an accidental anthrax of a 

 guinea-pig inoculated with tuberculous matter occurred 

 several times. In all cases freshly drawn-out glass capillary 

 pipettes had been used for performing the inoculation, and 

 also the other instruments had been carefully cleaned before 

 the inoculation. 



I myself had the following accidental contaminations : 

 A guinea-pig had been inoculated -with a culture of 

 bacillus anthracis, which I did not expect would produce 

 anthrax, the culture not being capable of starting new cul- 

 tures, the bacillar threads being all in a state of degeneration. 

 The animal, of course, remained unaffected. Some weeks 

 afterwards inspecting the guinea-pig, to my surprise, I found 

 the inguinal lymphatic glands at the side of the former 

 inoculation greatly swollen, filled with cheesy pus. The 

 animal was killed, and was found to be affected with general 

 tuberculosis, the cheesy matter of the tubercular deposits 

 containing the tubercle bacilli. Comparing my notes on 

 this animal with those of my friend Lingard, we found that 

 on the very day on which I inoculated the animal with my 

 anthrax culture we had inoculated several other guinea-pigs 

 with tuberculous matter. This tuberculous matter was 

 prepared in the same room in which I prepared the fluid 

 for my anthrax inoculation, but the instruments in the two 

 sets of experiments had not been the same. 



