344 ANTHRAX 



produced in animals, closely similar to those produced by the 

 bacilli themselves. Martin, to account for the symptoms of the 

 disease, considered that the fever was mostly due to the 

 albumoses, while the oedema and congestion were caused by 

 the alkaloid acting as a local irritant. Hankin and Wesbrook 

 arrived at the conclusion that the bacillus anthracis produces 

 a ferment which, diffusing out into the culture fluid, elaborates 

 albumoses from the proteids present in it. The bacilli also pro- 

 duce albumoses directly without the intervention of a ferment. 

 Marmier isolated from cultures in peptone solution a body which 

 gave no reactions of albuminoid matter, peptone, propeptone, 

 or alkaloid, and which he considered to be the toxin. It was 

 chiefly retained within the bacilli when these were growing in 

 the most favourable conditions, and was not destroyed by heat- 

 ing to 110 C. The toxin produced by the b. anthracis growing 

 in a fluid medium remains intimately associated with the 

 bacterial protoplasm, as such cultures when filtered are relatively 

 non-toxic. 



It cannot be said that great light has been thrown on the 

 pathology of the disease by these researches. The effects of 

 infection by the b. anthracis are those shared by all other 

 organisms producing inflammation, the tendency to oedema- 

 production of an unwonted degree being the chief special 

 feature. That toxic effects do occur in anthrax is probable, 

 for frequently, while the bacilli are still locally confined, there 

 may occur pyrexia and oedema spreading widely beyond the 

 pustule, but we have no definite information as to how these 

 effects are produced. In this disease we are probably dealing 

 with another example of the action of intracellular toxins, 

 regarding which, as in other cases, little is known. 



The Spread of the Disease in Nature. We have seen that 

 the b. anthracis rarely, if ever, forms spores in the body, and if 

 the bacilli could be confined to the blood and tissues of carcases 

 of animals dying of the disease, it is certain that anthrax in an 

 epidemic form would rarely occur. For it has been shown by 

 many observers that in the course of the putrefaction of such 

 a carcase the anthrax bacilli rapidly die out, and that after ten 

 days or a fortnight very few remain. But it must be remembered 

 that while still alive an animal is shedding into the air by the 

 bloody excretions from the mouth, nose, and bowel, myriads of 

 bacilli which may rapidly spore, and thus arrive at a very re- 

 sistant stage. These lie on the surface of the ground and are 

 washed off by surface water. At certain seasons of the year the 

 temperature is, however, sufficiently high to permit of their 



