MINERAL POISONS. 87 



is only a very slight degree of inflammation of 

 the alimentary canal : in other cases the inflam- 

 mation is considerable. It generally begins very 

 soon after the poison is administered, and is 

 greater or less according to the time which 

 elapses before the animal dies. Under the same 

 circumstances, it is, as I have already observed, 

 less in rabbits than in carnivorous animals. The 

 inflammation is greatest in the stomach and in- 

 testines; but it usually extends also over the 

 whole intestine. I have never observed inflamma- 

 tion of the oesophagus. It is greater in degree and 

 more speedy in talcing place, when arsenic is applied 

 to a wound than when it is taken into the stomach. 

 The inflamed parts are in general universally 

 red, at other times they are red only in spots. 

 The principal vessels leading to the stomach and 

 intestines are much dilated, and turgid with 

 blood ; but the inflammation is usually confined 

 to the mucous membrane of these viscera, which 

 assumes a florid red colour, becomes soft and 

 pulpy, and is separable without much difficulty 

 from the cellular coat, the latter presenting its 

 natural appearance. In some instances, there are 

 small spots of extravasated blood on the inner 

 surface of the mucous membrane, or immediately 

 beneath it, and this occurs independently of 

 vomiting. I have never, in any of my experi- 

 ments, found ulceration or sloughing of the 

 stomach or intestine ; but if the animal survives 

 for a certain length of time, after the inflam- 

 mation, has begun, it is reasonable to conclude 



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