EFFECTS OF VARIOUS PHYSICAL AND CHEMICAL AGENTS 99 



Ferrous sulphate: Mitchell and Reichert came to the conclusion that sul- 

 phate of iron in equal weights does not destroy the crotalus venom (0.03 gm. 

 each in i ex. water). 



Dialyzed iron: When dialyzed iron is added to a solution of venom all 

 of the proteids are precipitated, and the filtrate is found to give no reactions 

 for proteids with the xanthoproteic or picric acid tests. The precipitate is 

 brown and viscid and insoluble in water, but when injected into the tissue 

 the action of the venom quickly follows. The experiments were made with 

 moccasin venom. 



Ferric chloride: Being a powerful precipitant of proteins it quickly pro- 

 duces precipitate of the venom. 10 gm. of tincture of chloride of iron or 4 

 gm. of hquor ferric chloride destroys 0.015 gm. crotalus venom in 0.5 c.c. of 

 water. 



It is also very interesting to see that cobra venom is not markedly affected 

 by chloride of iron, although in some instances some delay in death was 

 observed. Mitchell and Reichert believe that this is due to the fact that the 

 active peptone-like principle of this venom is not affected by this iron prepa- 

 ration. 



In summing up their experiments Mitchell and Reichert make some special 

 allusions to the differences in toxic constituents of crotalus and cobra venoms, 

 as shown by them through the action of ferric chloride, and to the compara- 

 tively sHght destructive effects of different mineral acids. They pointed out 

 the efficient anti-venomous property of bromine. The work of Lacerda on 

 the destructive effect of potassic permanganate upon venom and the claim of 

 Brainerd that iodine exerts destructive influence upon crotalus venom have 

 both been confirmed by these investigators. The destruction of venom by 

 strong alkalies has also been established. 



The length of time of contact of these chemicals with venom was very 

 short and the mixtures were made just before the injections. 



Similar study was carried on by Kanthack^ with cobra venom and its 

 albumoses. He mostly employed fresh venom diluted with thymol to a 

 definite proportion. The standard was such as to make one minim of the 

 mixture able to kill a rabbit in 4 hours, and it was effected by adding 50 to 

 100 volumes of thymol to one volume of cobra venom. 



Chlorine water {freshly prepared) : Cobra venom was diluted with chlorine 

 water so as to contain the same percentage of venom as the thymol solution. 

 The mixture was allowed to stand for 24 hours and 4 days. At the end of 

 24 hours I minim still was fatal in 24 hours, while injection of 2 to 3 minims 

 after 4 days' contact had no effect. Thus a prolonged action of chlorine 

 water completely destroys the toxic action of cobra poison. 



Trichloride of iodide (10 per cent) : 2 c.c. of ICI3 added to 5 minims of the 

 standard venom solution destroyed the action of the latter in 24 hours. 



Carbolic acid (10 per cent)': Carbohc acid produces a distinct cloudiness 

 when added to a solution of native poison. After 24 hours the filtrate was 



1 Kanthack. The nature of cobra poison. J. of Physiol., 1892, XIII, 273. 



