122 Professor Thomas B. Fraser [March 20, 



This suggestion receives a further support from the fact, 

 observed in several experiments, that the longer before their adminis- 

 tration the two substances were allowed to remain together after they 

 had been mixed, the greater is the antidotal efficiency of the aiiti- 

 venene. Thus, while 1 • 3 c.c. per kilogramme of antivenene, mixed 

 with five times the minimum-lethal dose of venom, was followed by 

 death when the two had been mixed together five and also ten minutes 

 before administration, this mixture was, on the other hand, followed 

 by recovery when the interval before the administration was extended 

 to twenty minutes. In order to obtain uniform and comparable 

 results in the first series of experiments, it was therefore found 

 necessary to adhere, in all the experiments made with the larger doses 

 of venom, to a time limitation of not more than ten minutes before 

 the mixed substances were injected. 



I have also administered cobra-antivenene thirty minutes after a 

 dose one-twelfth larger than the minimum-lethal of the venoms, 

 respectively, of the Sejiedon hsemacliates, the Crotalus Tiorridus, and 

 the Diamantina serpent; and the animals experimented on have 

 recovered when the dose of cobra-antivenene was not smaller than 

 1 • 5 c.c. per kilogramme. This successful result is all the more 

 remarkable when the intensely destructive efi'ects produced by even 

 smaller doses of each, but especially of two, of these venoms is 

 recollected. 



The antivenene derived from rabbits which had been protected to 

 the extent that they had last received fifteen times the minimum- 

 lethal dose of the Diamantina venom has also been tested against the 

 Diamantina venom itself. When the two were administered together, 

 after having been mixed in vitro, this antivenene in a dose of • 5 

 (1/20) c.c. per kilogramme was able successfully to antagonise 

 slightly less than one-and-a-half the minimum-lethal dose of the 

 venom; but -025 (1/40) c.c. per kilogramme failed to do so. 



In the experiments which I have hitherto described, and, indeed, 

 apparently in all others made in this new subject of serum thera- 

 peutics, protection has been produced, and the antidotal properties 

 of the antitoxic blood-serum have been tested, by the subcutaneous, 

 or, less frequently, by the intravenous injection of the venom or 

 other toxic substance. No endeavour seens to have been made to 

 discover how far the same effects, or what effects, may be produced 

 by stomach administration. 



Anticipating that results of an interesting nature might be 

 obtained by this method of administration, I have adopted it for the 

 introduction of both antivenene and venom into the body, and the 

 results have even exceeded my anticipations. 



The plan followed was the simple one of mixing the substances, 

 previously dissolved in water, with a small quantity of milk, and 

 allowing white rats, which had not received any food for several 

 hours previously, to drink this milk. In the meantime, I will briefly 

 describe only those experiments in which antivenene was thus 



