THE MICROBIAL TOXINS. 67 



indirectly to the pyogenic substance. The toxins 

 in general retard the heart action. 



We will not speak of the distinctions it has been 

 sought to establish between the substances which 

 possess these different properties, but will at once 

 take up the discussion of several of the microbial 

 toxins. 



Anthrax Toxin* (from Bacillus Anthracis). — ^We 

 will describe the preparation of this toxin as a 

 type. 



The cultures of the bacillus are made in Liebig's 

 bouillon, to which has been added 0.1% of fibrin, 

 the whole being carefully sterilized for a long time 

 at iio°C. The cultures medium is inoculated with 

 a drop of blood taken from the heart or spleen of an 

 animal that has died of anthrax. At the end of a 

 week, the culture is filtered, and the filtrate acid- 

 ulated with a little acetic acid and precipitated by 

 adding powdered ammonium sulphate. The floccu- 

 lent precipitate is collected, washed, dissolved in 

 distilled water, and dialyzed. The dialyzed solu- 

 tion is concentrated in vacuo at 40-45° C, and 

 precipitated by adding to it alcohol. The precipi- 

 tate formed is then collected and dried. f 



* Arloing, Cornevin, Thomas: Le Charbon SympiomaUque, 

 ist edit., Paris; and Le Dantec: La Bact^ridie du Charbon, 

 Masson, pubL; Straus: Le Charbon des Animaux et de I'Homme 

 Paris, 1887. 



t Hankin: British Medical Journal, Oct. 12, 18S9, and July 

 12, 1890.; 



