258 VENOMS 
we should have a toxin and antitoxin side by side; for the 
reasons indicated above, this toxin (lecithide) and antitoxin (anti- 
venomous serum) would be no longer capable of combining ; but 
the toxin (lecithide), thanks to its heemolytic properties, could easily 
be demonstrated. 
It is precisely this desideratum that J. Morgenroth has suc- 
ceeded in realising, by means of hydrochloric acid, which renders 
it possible to dissociate the neutral mixture, torin + antitoxin, 
into its constituent elements, and then to obtain a lecithide. 
Experiments show that the quantity of lecithide thus restored 
absolutely corresponds to that of the cobra-hæmolysin originally 
added to the antitoxin, and that the antitoxin set free is not 
injured by the hydrochloric acid, even after twenty-four hours of 
contact. It is sufficient to add the quantity of soda or of ammonia 
necessary for the neutralisation of the acid, in order to see the 
antitoxin reappear in its original strength. 
It is therefore possible, by causing hydrochloric acid (in a 
solution not stronger than 3 per cent.) to act on a neutral mixture 
of cobra-hemolysin (toxin) and antitoxin, to set the former at 
liberty in the form of lecithide, to withdraw the latter from the 
action of the antitoxin, and to demonstrate its presence, owing to 
its hemolytic properties. 
It has been found by Kyes and Sachs that, under the influence 
of hydrochloric acid, cobra-hæmolysin becomes resistant to heat to 
such an extent that it 1s not destroyed even by prolonged heating 
at 100° C. 
If to a neutral mixture of toxin + antitoxin we add a small 
quantity of hydrochloric acid, and then heat the mixture at 100° C., 
the antitoxin being in this case destroyed, we shall recover the 
whole of the toxin originally employed. 
Therefore, as was shown by me so long ago as 1894, if the 
mixture of toxin + antitoxin produces a chemical combination 
between the two substances, this combination is unstable, and can 
be effectively broken up into these two constituent elements by 
various influences. 
