124 CHEMICAL EQUILIBRIA 



poison is more rapidly weakened than poison iiy 

 larger lumps. The antivenin had not changed its" 

 power sensibly during the six years. The innocuous 

 precipitate which is formed by the combination of 

 cobra poison with antivenin gave back the whole 

 quantity of its toxin content unweakened when 

 heated to 72 with a small quantity of hydrochloric 

 acid, even after storage for five years. 



The adherents of the old EI-IRLICH theory object 

 to the use of the laws of equilibria on the binding^ * 

 of toxins, that the processes in this case are not 

 reversible, because the compound of toxin and 

 antitoxin changes with time, so that it becomes 

 less dissociable. This last assertion is not true 

 in some cases, as that told of by CALMETTK, 

 but in other cases it is true, as we shall soon 

 see. But on the same ground we might oppose 

 the use of reversible processes for the calcula- 

 tions in thermo-dynamics, because ideal reversible 

 processes are in general not realized in nature. 

 Every physicist knows that such opposition is 

 unjustified. Such an irreversible process was 

 discovered by DANYSZ in the so-called DANYSZ 

 phenomenon. DANYSZ found in experiments with 

 ricin or with diphtheria poison that if we have a 

 certain quantity of poison and a (not too small) 

 quantity of its antibody and mix them at once, the 

 mixture possesses a less degree of toxicity than the 

 mixture which results if we take only a part, say 

 50 per cent, of the poison and mix it with the 

 total quantity of antitoxin and after a time add 



