1896.] on Immunisation against Serpents* Venom. 121 



lethal, one-and-a-half the minimum lethal and twice the minimum- 

 lethal dose of cobra venom. With the first of these doses, recovery 

 occurred with '5 c.c, '45 c.c, and '42 c.c. ; but death with *4 c.c, 

 •3c.c., and '25 c.c. of antivenene, administered thirty minutes before 

 the venom. With one-and-a-half the minimum-lethal of venom, 



2 • 9 c.c. and 2 * 7 c.c. of antivenene were able to prevent death ; while 

 2*6 c.c, 2*5 c.c, 2*3 c.c, and 2 c.c. each failed in doing so. With 

 twice the minimum-lethal dose of venom, recovery occurred when the 

 doses of antivenene were 5 c.c, 4*5 c.c, and 4 c.c; but 8-9 c.c, 

 3*8 c.c, 3*5 c.c, 2-5 c.c, and 2 c.c were insufficient to prevent death. 



In the fourth series, where the results give the truest indications 

 of the antidotal value of antivenene in the actual treatment of snake- 

 poisoning, it was found that recovery occurred in the experiments in 

 which '8 c.c, '7 c.c, and '65 c.c. per kilogramme of antivenene was 

 injected thirty minutes after an assuredly minimum-lethal dose 

 ( * 00025 per kilo.) of venom ; but that the antivenene was insufficient 

 in quantity to prevent death when • 6 c.c. or any smaller quantity 

 was administered. In this series, further, it was found that 3 • 4 c.c. 

 and 3 • 2 cc per kilogramme of antivenene were sufficient doses to 

 prevent death after one-and-a-half the minimum-lethal dose of 

 venom, but that 3 c.c, 2 • 8 c.c, and 2 * 5 cc. per kilogramme were 

 insufficient. In a corresponding series of experiments made with 

 the antivenene derived from rabbits which had last received thirty 

 and fifty times the minimum-lethal dose of cobra venom, it was found 

 that 5 c.c. per kilogramme of this antivenene was the smallest dose by 

 which death could be prevented in an animal which had received 

 twice the minimum-lethal dose of venom thirty minutes previously. 



Attention is conspicuously drawn by these facts to the remark- 

 able difference in the dose of antivenene which is required to prevent 

 death when it is mixed with the venom before administration, as con- 

 trasted with the doses required when the two substances have not 

 previously been mixed together. Eestricting attention to the experi- 

 ments in each series in which the dose of venom was the same — to 

 the experiments with one-and-a-half the minimum-lethal dose, for 

 instance — it a2)pears that in order to prevent death, when this dose 

 was mixed with antivenene before administration, only *24 c.c. of 

 antivenene is required ; whereas, when both substances were injected 

 simultaneously, but under the skin at different parts of the body, the 

 required dose of antivenene is 3 * 5 cc ; when the antivenene was 

 injected thirty minutes before the venom, it was 2 • 7 cc. ; and when 

 the venom was injected thirty minutes before the antivenene, it was 



3 • 2 cc per kilogramme. 



It is impossible to consider the great difference between the dose 

 of antivenene recjuired when the two substances, though in each case 

 simultaneously administered, are, in the one case, mixed together 

 before injection, and in the other not so mixed, without again having 

 the suggestion originated that the antidotism is the result of chemical, 

 and not of physiological reactions. 



