ON THE DETECTION OP ARSENIC. 
285 
Having concluded with the exposition of the distinctive 
characters of arsenious acid, we now come to the considera- 
tion of this substance under a medico-legal head, which em- 
braces the application of the above cited experiments to cases 
of poisoning by it. 
In order to know whether a suspected substance, which has 
occasioned death, contains any arsenic — 
1st. Ascertain if there be any of it left remaining; upon 
finding which, you submit it first to the action of fire, to [de- 
stroy organic matters, then dissolve it in boiling water, and 
test it with chemical reagents, to see if it comports with the 
character of arsenic. 
2d. If what remains should be a liquid, then evaporate a 
portion of it in a porcelain capsule, and examine the residue, 
by employing the means for reducing arsenic to the metallic 
state, which only can be regarded as certain proof. 
3d. In case all the poison has been swallowed, you must 
act upon the matter ejected by vomiting, separating first the 
fluid parts, by means of a filter, which liquid you test with 
the reagents. Search among the solid parts for solid, granular 
particles, which, thrown upon burning charcoal, give out a 
white smoke with an alliaceous odor. If these experiments 
furnish no result, it will be necessary to boil a portion of the 
solid parts with about twelve times its weight of distilled wa- 
ter for fifteen minutes, then filter, and submit the liquid to the 
tests above indicated. 
4th. The matters collected after death, in the stomach and 
intestines, should be submitted to the same investigations: 
these may be summed up under these three principal heads: 
(1.) Search with the naked eye, and afterwards with a lens, to 
ascertain if there be not some solid particles of arsenious acid 
in these matters, and, if it be possible, extract them mechani- 
cally for particular examination. (2.) If these matters contain 
no visible particles of arsenic, strain them forcibly through a 
piece of white linen to separate the liquid portion, which 
should be filtered and examined with care. (3.) If these trials 
have not led to the discovery of arsenious acid, treat the ex- 
