26 



Prof. Pedler on Cobra Poison. 



[Jan. 17, 



as before, I used weighed quantities of the dried fresh poison dissolved 

 in water, and added known quantities of a standard solution of 

 platinum tetrachloride ; the results of these injections into dogs are 

 shown in the table below, and in no instance did they show the slightest" 

 indication of any physiological action whatever. These animals were 

 still alive when this paper was written. 



Table D. — -Injection of Mixture of Cobra Poison and PtGli into Dogs. 



No. of 

 Expt. 



Weight of 

 Dog. 



Weight of Cobra 

 Poison used. 



Weight of 

 PtCl 4 used. 



Duration 

 of Expt. 



Pvesult. 



1 



2 

 3 



38 lbs. 

 25 „ 

 35 „ 



§ grain = *0324 gram 

 1 grain = "0648 gram 

 3 grains = '1944 gram 



•065 gram 

 *13 gram 

 •30 gram 





Not affected 



J5 



If we accept the conclusion that % grain of cobra poison hypoder- 

 mically injected will kill a dog under ordinary circumstances, in the 

 three experiments under notice the quantities of cobra poison used 

 were sufficient to kill three, six, and eighteen dogs respectively ; and yet 

 in no case did the dog show the slightest indication of cobra poisoning. 

 I have not tried larger quantities than three grains of poison, as the 

 volume of liquid which has then to be injected becomes inconveniently 

 large ; even in Experiment ISTo. 3 in Table D no less than four or five 

 separate hypodermic injections had to be made, to the great incon- 

 venience of the dog experimented upon. From these results I think 

 it may safely be said, that the compound which cobra poison produces 

 when brought into contact with an aqueous and dilute (5 per cent.) 

 solution of platinum tetrachloride is quite inert and physiologically 

 inactive, though of course it does not follow that this substance can 

 be used as an antidote in cases of snake poisoning. If I may be 

 allowed the expression, platinum tetrachloride appears to be a chemical 

 antidote to cobra virus, but whether it will be found to be a physio- 

 logical antidote can only be settled by extensive researches. 



Next, then, with a view to ascertain tentatively whether platinum 

 tetrachloride can be used as an antidote, in the ordinary sense of the 

 word, to snake poisoning, I have tried two sets of experiments de- 

 scribed below. The results which I have obtained from this third series 

 of experiments, although interesting and to a certain extent hopeful 

 in their nature, have not, I am sorry to say, in any case shown that 

 life can be saved by this means. As a preliminary step in the eluci- 

 dation of this very important question, I have made some experiments 

 on fowls and dogs by first hypodermically injecting known quantities 

 of poison more than sufficient to kill, and after a definite interval 

 injecting known quantities of the standard solution of platinum tetra- 

 chloride, at or near the same spot where the first injection was per- 



