ANTHRAX. 463 



anthrax bacillus produces any soluble extracellular or 

 intracellular poison capable of affecting susceptible ani- 

 mals, and concludes that it is highly improbable that 

 the anthrax bacillus produces any toxic substance at all. 



The susceptibility of the anthrax bacillus to the influ- 

 ence of heat, cold, antiseptics, etc. not only permitted 

 Buchner, Behring, and others to produce biological curi- 

 osities in the form of bacilli unable to bear spores and 

 robbed of their pathogenic powers, but also suggested 

 to Pasteur the important practical measure of protective 

 vaccination. Pasteur found that the inoculation of non- 

 virulent bacilli into cows and sheep, and their reinocula- 

 tion with slightly virulent bacilli, gave them the ability 

 to withstand the action of highly virulent organisms. 

 Loffler, Koch, and Gaffky, however, found that these 

 immunized animals were not absolutely protected from 

 intestinal anthrax. 



The methods of diminishing the virulence of the 

 anthrax bacilli are numerous. Toussaint, who was cer- 

 tainly the first to produce immunity in animals by inject- 

 ing them with sterile cultures of the bacillus, found that 

 the addition of 1 per cent, of carbolic acid to blood of 

 animals dead of anthrax destroyed the virulence of the 

 bacilli ; Chamberland and Roux found it removed when 

 0.1-0.2 per cent, of bichromate of potassium was added to 

 the culture-medium ; Chauveau used atmospheric pressure 

 to the extent of six to eight atmospheres and found the 

 virulence diminished ; Arloing found that direct sunlight 

 operated similarly ; Lubarsch found that the inoculation 

 of the bacilli into immune animals, such as the froe, and 

 their subsequent recovery from its blood, diminishes the 

 virulence markedly. 



Protection can be afforded in still other ways. The 

 simultaneous inoculation of bacteria not at all related to 

 anthrax will sometimes recover the animal, as Hiippe 

 found. Hankin found in the cultures chemical sub- 

 stances, especially an albuminose, which exerted a pro- 

 tective influence. Chamberland has shown that pro- 



