RELATION OF PATHOGENIC TO SEPTIC BACTERIA. 61 



after one month ; a sample examined under the microscope 

 showed hardly a trace of a well-preserved bacillus and no 

 spores. I inoculated a test-tube of pork broth with it and 

 produced a beautiful growth of typical Bacillus anthracis; 

 some of these extended up to the surface and formed a copious 

 crop of spores. This killed a guinea-pig three weeks after it 

 was established. In the above case it was evidently only a 

 chance of our missing to have an active bacillus in the samples 

 which we used for the inoculation of the guinea-pig; but more 

 luckily we got one in the sample used for the inoculation of 

 the pork broth in the test-tube. 



The above guinea-pig which escaped anthrax was not 

 immune against the introduction of the active virus, since it 

 succumbed to an inoculation afterwards with bacillus and 

 spores of a cultivation in gelatine pork. 



All these observations seem to point out that there are two 

 conditions to be borne in mind : («) a peculiarity possessed by 

 mice and not possessed by guinea-pigs and rabbits ; and (b) a 

 peculiar change that the bacilli of the artificial cultivation 

 undergo as the duration of incubation advances. As regards 

 the first of these conditions it is known through Chauveau 

 that Algerian sheep are altogether refractory against anthrax, 

 and consequently these Algerian sheep possess a peculiarity 

 not owned by the French sheep. 



According to Pasteur the influence of the air (oxygen) on 

 the artificial cultivations of the micrococcus of fowl cholera, 

 and the artificial cultivations of the Bacillus anthracis has 

 a deleterious effect, inasmuch as it gradually weakens and 

 ultimately altogether destroys the activity of the respective 

 organisms. As I have no experience of the micrococcus of 

 fowl cholera, I cannot say anything about it ; but of the 

 Bacillus anthracis I can say something from my own 

 observations, and I will undertake to offer to this theory of 

 Pasteur, viz. of the deleterious influnace of the oxygen of the 

 air on the Bacillus anthracis, an unconditional opposition. 

 If in a cultivation we meet with a copious production of typical 



