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 hsemolytic 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, toxin + 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-hsemolysin 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-hsemolysin (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 hsemolytic properties. 



It has been found by Kyes and Sachs that, under the influence 

 of hydrochloric acid, cobra-hsemolysin becomes resistant to heat to 

 such an extent that it is 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. 



