ANTHRAX POISON. 181 



time ; and, moreover, the toxines produced in these exudations 

 would surely have undergone renewed metabolism, and have 

 been fixed by the receptors, so that only very slight traces could 

 have been left behind. In addition to this the exudations in 

 this case would doubtless contain antitoxines, which would render 

 a correct deduction still more difficult. At the same time, it is 

 possible that such exudations may be used as suitable natural 

 culture-media, in which, eventually, toxines may be detected. 



Be this as it may, it is impossible to draw any conclusion from 

 these experiments by CONRADI as to the non-existence of a true 

 toxine. Speaking generally, such experiments are not suitable 

 for determining the question of the production of poison by 

 a bacterium ; for other poisons of simpler nature may also be so 

 altered or destroyed after producing injurious effects, or even by 

 their physiological action, that no trace that can be detected 

 remains in the fluids of the tissues. Even many alkaloids, such 

 as cytisine, disappear in the organism without leaving a trace. 

 It is not safe, in view of the manifold attacks to which a poison 

 is exposed in the body, to draw negative conclusions as to the 

 non-existence of this poison ; only positive results would be 

 conclusive here. Thus CON R ADI'S experiments only contribute 

 negative evidence towards a decision on this point ; once more 

 a means of discovering the hypothetical poison has proved un- 

 workable; the question of the existence of the poison still 

 remains open. And, in this connection, it must not be lost sight 

 of that the existence of an anthrax poison is really an etiological 

 postulate ; for there are many cases of anthrax with fatal results 

 where general bacterial infection is out of the question, and 

 where it has been very difficult or impossible to detect living 

 bacilli in the organism. Surely such cases can only be explained 

 as cases of poisoning. Hence, notwithstanding Conradi's results, 

 further search must be made for the poison. 



On the other hand, no objection can be offered to the experi- 

 ments made by CONRADI to determine whether the anthrax 

 bacillus produced a specific endotoxine, which is only liberated 

 after the death and decomposition of the cell in an analogous 

 manner to yeast, invertase, and zymase. He killed the bacilli 

 by means of toluene, or by freezing, or disintegrated them by 

 Buchner's method. In every instance the result was absolutely 

 negative. Nor could he isolate toxalbumins from the organs, 

 either by means of the method of Brieger and Frankel or by 

 that of Marmier. 



Hence, the present state of affairs is as follows : 



Convincing proof of the existence of a true anthrax toxine, 



