TOXIX AND ANTITOXIN. 543 



7. "The power to excite the formation of antibodies is due to 

 certain peculiarities in the chemical structure of the substance which 

 excites this antibody production. A prerequisite for this produc- 

 tion as well as for toxic action is the chemical union of the foreign 

 substance with certain particular constituents of the cells." 



This, I may say, is a short, though not particularly good, resume 

 of the side-chain theory. 



8. "The non-poisonous toxin-antitoxin combination also lacks 

 the power to excite the production of antitoxin. The entire chemi- 

 cal character of this combination is different from that of the uncom- 

 bined substances." 



This, too, is one of the fundamental principles of my theory, and 

 is most readily explained by the assumption that the antitoxin fits 

 into the same group which effects the union of the toxin with the 

 susceptible cells. Furthermore, I really see no reason why Gruber 

 should make a special point of the fact that the chemical character 

 of the toxin-antitoxin combination has changed. That is merely 

 a trick of speech which will make but little impression on the scientific 

 reader. 



That the antitoxins are nothing but thrust-off receptors capable 

 of uniting with the poison this assumption, together with its 

 immediate consequence that the toxin-antitoxin combination must 

 be non-poisonous, is the key to my entire theory. We are, in 

 fact, dealing with an extremely important law which Weigert 

 and I compared to the principle of the lightning-rod and which 

 v. Behring briefly expressed as follows: "The same substance in 

 the living body which, when in the cell, is the prerequisite of a poison- 

 ing, becomes the healing agent when it is present in the blood.' 7 

 This law applies not only to the toxins but possesses general applic- 

 ability. I may here refer the reader to Ransom's experiments, which 

 show that the cholesterin in the red blood-cells causes haemolysis 

 by saponin, while at the same time the cholesterin of the serum 

 causes an inhibition of this poisoning. 



Gruber, however, thinks that it has not been proved that the 

 haptophore group, which anchors the toxin to the vital constituent 

 of the protoplasm, is the same which anchors the toxin to the anti- 

 toxin. A year and a half ago he expressed this quite clearly as 

 follows : l 



"Ehrlich may have demonstrated that the toxin is bound to 

 1 Wiener klin. Wochenschrift, 1901, No. 50. 



