360 POISONS, CONTAGIONS, MIASMS. 



fetid, putrid mass, retain all their properties unchanged if ar 

 senious acid be added to the water. The arsenious acid, combining 

 with these tissues, gives to them the power of resisting decay 

 and putrefaction. The putrefaction of flesh, or of blood, and 

 the fermentation of sugar, are not checked or prevented by ar- 

 senious acid. 



It is further known that the parts of a body which come in con- 

 tact with these substances during poisoning, and which therefore 

 enter into combination 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 combi- 

 nation 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 apper- 

 tains to their vital condition, viz. that of suffering and effecting 

 transformations ; or, in other words, organic life must be de- 

 stroyed. If the poisoning is merely superficial and the quantity 

 of the poison so small that only individual parts of the body ca- 

 pable 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 

 uncertain ; for cases may happen, in which no apparent indica- 

 tion of change can be detected by simple observations of the parts, 

 because, as has been already remarked, death may occur without 

 the destruction of any organs. 



When arsenious acid is administered in solution, it may enter 

 into the blood. If a vein is exposed and surrounded with a solu- 

 tion of this acid, every blood-globule will combine with it, that is, 

 will become poisoned. 



The compounds of arsenic, which have not the property of en- 

 tering into combination with the tissues of the organism, are 

 without influence on life, even in large doses. Many insoluble 

 basic salts of arsenious acid are known not to be poisonous. The 

 substance called alkargen, discovered by Bunsen, has not tho 



