180 TOXINES AND ANTTTOXINES. 



been a true toxine. The poison was weakened by gold chloride, 

 platinum chloride, and calcium chloride. 



And, in the second place, it apparently produced only a slight 

 immunity, and that, too, not invariably. Hence, in any case, it 

 could not have been a weakened toxine, since then the reduction 

 in toxic power must have been accompanied by the more ener- 

 getic immunising effect. 



CONRADI (loc. cit.) has recently once more investigated the 

 question whether anthrax bacilli form a soluble diffusible poison, 

 and has, if we may anticipate, arrived at an absolutely negative 

 result. He started from the point of view that it was the multi- 

 plicity of the nutrient substrata used by previous investigators 

 that was frequently responsible for the diametrically opposite 

 results. Hence he decided to search for the anthrax poison in 

 the body of the animal. For this purpose he used peritoneal 

 exudations and extracts of organs (liver and spleen) of infected 

 animals, and found both, after nitration through a Kitasato or 

 Chamberland filter, to be invariably devoid of any toxic effect. 



Moreover, he introduced virulent bouillon cultures into the 

 abdominal cavity of guinea-pigs, which was then enclosed in 

 a bacteria-proof bag made with the inner membranes of the reed 

 (Phragmites communis), and in this case, too, there was no toxic 

 action. 



Two objections can be offered to CONRADI'S results. 



The reed experiments only prove that there does not exist any 

 soluble and diffusible anthrax poison, but do not exclude the 

 possibility of there being a non-diffusible toxine, just as other 

 haptines e.g., certain ferments are also indiffusible. And, 

 indeed, the results obtained by ARLOING (vide supra), who found 

 a poison in unfiltered cultures, whereas the majority of investi- 

 gators found nothing in filtered cultivations, render it not 

 improbable that anthrax toxine may be readily retained by 

 filters and membranes. 



The second objection appears to me more important. Even 

 granting the existence of a true haptophore toxine of anthrax, it 

 is possible that under certain conditions it may not be found 

 again in the organs and fluids of the infected bodies of susceptible 

 animals, owing to its entering into stable combination with the 

 receptors ; the poisons of tetanus and diphtheria can, even under 

 normal conditions, only be found again in the blood and organs 

 of infected animals after the introduction of large doses. 



It is true that living micro-organisms were present in these 

 exudations, but, at the same time, these could not have been able 

 to have used their toxine-producing powers for any length of 



