422 Drs. C. J. Martin and T. Cherry. 



of diphtheria which were identical in principle with those of 

 Calmette and Wassermann. In this case, however, it is the toxin 

 which is destroyed at the lower temperature (60 C. Roux and 

 Yersin), whereas the antitoxic properties still remained after heating 

 the serum to 70 C. Mixtures of the two in such proportions as to 

 cause no symptoms when injected into a guinea-pig were made. 

 After heating such mixture to a temperature sufficient to destroy the 

 toxin, the mixture was discovered now to possess antitoxic properties 

 which could be titrated against a fresh amount of toxin. 



2. Observations favouring the interpretation that the action of Antitoxins 



is direct. 



The view that the operation is a direct one has always received 

 support from the general truth of the " law of multiples," on which 

 indeed the antitoxin notation has been founded. It is further 

 strengthened by the observations of Kanthack and Ehrlich. 



Kanthack,* in 1896, demonstrated that the influence of cobra 

 poison in preventing the coagulation of shed blood, observed by 

 Cunningham, was prevented by the previous admixture of some of 

 Calmette's an ti venomous serum to the solution of cobra poison. 



Ehrlichf found that if a solution of ricin, be added to defibrinated 

 blood ( ? animal) the corpuscles are precipitated in a clump. A 

 ricin solution of the same strength, but containing a little serum 

 from an animal immunised against ricin, failed to produce this result. 



Within the last few days we have received a short account of 

 some experiments by Stephens and Meyers, J bearing upon the same 

 point. Cobra poison exercises a haemolytic action upon blood in 

 vitro. After admixture of the poison with antivenomous serum 

 this heemolytic action was absent. The necessary precaution of 

 making the solution of the venom with saline solution approximately 

 iso tonic with blood serum was taken. 



Before relating the results of our own experiments we may point 

 out one source of fallacy in the conclusions drawn by Wassermann, 

 Calmette, Nikanorow, and Marenghi, viz., that they take no account 

 of the factor, time, which may be a very important element in any 

 possible chemical interaction between toxins and antitoxins. Every 

 chemical reaction has a certain definite velocity coefficient, and the 

 rapidity of action under any circumstances where the reacting com- 

 pounds are in solution depends upon this coefficient, and also upon 



* Demonstrated at meeting of Physiol. Soc., October 1896 (not published in 

 Proceedings) . 



t ' Fortschr. d. Med.,' 1897, No. 2. 



J " Eeport of Proceedings of Path. Soc. of London," ' Lancet,' March 5, 1898, 

 p. 644. 



