Means of detecting Arsenic in the Animal Body, §c, 281 
‘if not the sulphate of iron from which it was made. Again, he 
should lay but little stress upon the examination of the intestinal 
liquid, but direct his attention particularly to the organs. This, 
together with circumstances peculiar to each case, will explain 
away any doubt that might arise. 
It ought to be perfectly understood, that the fact of the per- 
xide of iron containing a small quantity of arsenic, should be 
considered rather as a light to guide the chemist in his resear- 
ches, than as a stumbling-block that might cause him to fall into 
error. pehis 
Does arsenic exist normally in the animal tissues ? Ys 
This rhaps has been one of the most interesting questions 
ever proposed to chemists, and the investigations that it has 
given rise to, serve to show the almost perfection of their science, 
for were it supposed that the whole animal frame contained but 
‘one fiftieth of a grain of arsenic, the chemist would not despair 
not only of being able to detect it, but also of fixing its locality. 
As it regards the bones, it has been clearly se hrs that. 
_ they contain arsenic in a minute quantity, but sufficient to place 
the fact beyond the smallest doubt. | | i 
ether it exists in the muscles or not, is a question by no 
means settled. It is true, that with the aid of Marsh’s apparatus 
there can be obtained from muscles digested a long while in nitric 
acid, taches which are of different shades, such as brilliant white, 
brilliant yellow, and rusty color; they are volatile and not 
Soluble in nitric acid. Many have supposed their composition 
o be sulphur with an infinitely small quantity of arsenic. I 
think that these taches can be more easily accounted for by sul- 
phur and phosphorus, both of which exist in the muscles, and I 
amsorry that there is neither time nor opportunity to examine 
into the truth of this supposition. Nevertheless, whether they 
Contain arsenic or not, the taches obtained have but one charac- 
letistic belonging to that of arsenic, volatility. 
The next part of this question is very important ; it is whether 
the organs, such as the liver, spleen, heart, é&c., contain normal 
‘senic.. "The reason of its importance is, that it is upon them 
that we should place considerable reliafice, in the examination of 
the body of a person supposed to have been poisoned by arsenic. 
To this we answer, that not the smallest trace has been detected 
many of them; and the answer is based, not upon the few ex- 
“e 
