INORGANIC POISONS. 33/ 



influence of air and water ; but if they are digested 

 for some time with arsenious acid or corrosive sub- 

 limate, they may subsequently be exposed to all the 

 influence of the atmosphere without altering in 

 colour or appearance. 



It is further known that those parts of a body, 

 which come in contact with these substances during 

 poisoning, and which therefore enter into combi- 

 nation with them, do not afterwards putrefy ; so that 

 there can be no doubt regarding the cause of their 

 poisonous qualities. 



It is obvious that if arsenious acid and corrosive 

 sublimate are not prevented by the vital principle 

 from entering into combination with the component 

 parts of the body, and consequently from rendering 

 them incapable of decay and putrefaction, they must 

 deprive the organs of the principal property which 

 appertains to their vital condition, viz. that of suf- 

 fering and effecting transformations ; or, in other 

 words, organic life must be destroyed. If the 

 poisoning is merely superficial, and the quantity of 

 the poison so small, that only individual parts of 

 the body which are capable of being regenerated 

 have entered into combination with it, then 

 eschars are produced a phenomenon of a secondary 

 kind the compounds of the dead tissues with the 

 poison being thrown off by the healthy parts. From 

 these considerations it may readily be inferred that 

 all internal signs of poisoning are variable and un- 

 certain ; for cases may happen, in which no apparent 



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