qi6 Mr. Brodie's Observations and Experiments 
contact with the inner surface of these organs, even though 
taken in large quantity and in substance; and in animals which 
are capable of vomiting, by much the greater part is rejected 
from the stomach very soon after it has been taken in. Hence, 
though a few particles of arsenic are sometimes found en- 
tangled in the mucus, or in the coagulum of extravasared 
blood, and adhering to the inner surface of the stomach, I 
have never seen it in such a quantity as might be supposed 
capable of producing a slough. In one instance, where a dog 
bad swallowed a large quantity arsenic in substance, a brown 
spot, about an inch in diameter, was observed after death on 
the inner surface of the cardiac extremity of the stomach, 
having so much of the appearance of a slough, that at first I 
had no doubt of it being so ; but on examination this proved 
to be only a thin layer of dark coloured coagulum of blood, 
adhering very firmly to the surface of the mucous mem- 
brane, and having a few 7 particles of arsenic entangled in it. 
On removing this the mucous membrane still appeared of a 
dark colour; but this was also found to arise from a thin 
layer of coagulum of blood between it and the cellular coat. 
The mucous membrane itself was inflamed ; but otherwise in 
a natural state. I have observed a similar appearance, but oc- 
cupying a less extent of surface, several times. In the Hun- 
terian Museum there is a human stomach, which was preserved 
to show what was considered as a slough produced by the 
action of arsenic. On examining this preparation, I found that 
the dark coloured spot, which had been supposed to be a slough, 
was precisely of the same nature with that just described. 
Although the affection of the stomach and intestines from 
arsenic is not the cause of death, under ordinary circumstances,, 
