THE CONSTITUENTS OF DIPHTHERIA TOXIN 483 



but consists of several constituents of different toxicity (and these 

 toxicities bear a simple reciprocal relation to each other). Of these 

 constituents the toxin possessing the highest chemical affinity is 

 neutralized first. 



A similar conclusion has actuall} 1 been drawn in the case of toxin ; 

 the toxin first neutralized (the strongest) has been called prototoxin, 

 the next deuterotoxin, the next tritotoxin, etc. The final very 

 weak toxins are called toxones." 



The findings of Arrhenius and Madsen are thus seen to be directly 

 opposed to my statement that diphtheria poison is composed of 

 several constituents. In view of the exceeding importance of the 

 subject I cannot avoid entering the discussion and state the reasons 

 which cause me to maintain my views absolutely and without any 

 modification. 1 



The new views of the authors in question will doubtless lead many 

 to wonder how I could err in so simple a matter and employ compli- 

 cated theories when the simplest conceptions of chemistry would have 

 sufficed. It must seem strange that I, who have followed this sub- 

 ject for years and have busied myself especially with chemical studies, 

 should have failed to discover this very ready explanation. As a 

 matter of fact, however, I too began with the conception, now held 

 by Arrhenius and Madsen, that in the union of toxin and antitoxin 

 we were dealing with a phenomenon of incomplete neutralization. A 

 more thorough analysis of diphtheria poison (my publications refer 

 only to this poison) compelled me, however, to adopt more complex 

 explanations. 



At the very outset of my investigations I discovered that tetano- 

 lysin and its antitoxin possess weak affinities, and I devised the tech- 



1 Gruber, whose experiments especially devised to refute my theory 1 was 

 able to show were incorrect, has employed the opportunity to side with 

 Arrhenius and Madsen, and to announce that their observations "will give 

 this entire spook of side-chain theory its quietus," No one who knows any- 

 thing about this subject needs be told that the question as to whether diph- 

 theria poison is made up of one or more substances has nothing to do with the 

 side-chain theory. When 1 formulated this theory I too believed the diph- 

 theria poison to be a simple substance, and when subsequently 1 felt compelled 

 to differentiate several components in the poison 1 always emphasized that 

 the separate components differed only in their toxophore group and were 

 similar so far as the haptophore groups were concerned, the groups which give 

 rise to antitoxin formation (see my reply to Gruber in Munch, med. Wochenschr 

 1903, Nos. 33 and 34). 



