194 A MANUAL OF BACTERIOLOGY 



for two minutes, five minutes, and ten minutes before 

 heating, killed the animals in thirteen hours, fifteen hours, 

 and twenty-three hours respectively (the control animal 

 with the same dose of venom died in nine hours), but after 

 fifteen minutes the same mixture rendered the animal 

 ill, but it survived, while after thirty minutes no toxic 

 symptoms ensued. 



At one time it was stated that by electrolysis of toxins 

 small amounts of antitoxin are formed, but this is very 

 questionable. Electrolysis destroys the toxicity of toxins 

 by the production of acids, chlorine, and hypochlorites. 



Ehrlich's views have been opposed, principally on physico- 

 chemical grounds. Thus, Danysz observed that if an excess of 

 ricin or diphtheria toxin be brought into contact with its corre- 

 sponding antibody, the degree of neutralisation depends on the 

 manner of mixture. If the toxin be added to the antitoxin in 

 two fractions, allowing a considerable time to elapse between the 

 additions, the mixture contains a much larger amount of free 

 toxin than is the case when the whole (and same) amount of toxin 

 is added at once to the antitoxin. This phenomenon, known as 

 the " Danysz or toxone effect," seems inexplicable if toxin and 

 antitoxin have relations the same as a strong base and a strong 

 acid. 



Arrhenius, Dreyer, and Madsen maintain that the phenomena 

 observed in the toxin -antitoxin reaction are explicable on the 

 hypothesis that the rate of reaction avidity of the toxin 

 decreases as antitoxin is added, that the interaction is a slow one, 

 and that different fractions of the toxin are progressively neutra- 

 lised by the added antitoxin, but more and more slowly. On 

 these grounds they consider that there is no reason to regard 

 the diphtheria poison as a highly complicated body. Whereas 

 Ehrlich considers the toxin and antitoxin to combine with great 

 avidity, analogous to the combination of a strong base with a 

 strong acid, e.g. NaOH with HC1, these critics believe the avidity 

 of antitoxin to be feeble, analogous to the combination of am- 

 monia with boric acid, in which, as more and more acid is added, 

 the amount of free ammonia decreases, but more and more 

 slowly, in correspondence with a hyperbolic curve. The pheno- 



