(Translation from original article)
Legal Medicine
(Continuation of the report of Mr. Larue)
8 October 1857.
A sample of the original liquid, the colour having again been removed with chlorine, was divided into
two parts: the first, to which was added ammonia and ammonium carbonate, was treated with sodium
phosphate. After being vigorously stirred, no precipitate formed and there was no reaction after half
an hour. Therefore, an absence of magnesium.
The second part of the liquid produced no precipitate when treated with platinum bichlorate. Therefore,
an absence of potassium and ammonia.
Not having any potassium antimoniate to hand, the examination for sodium did not proceed.
Marsh apparatus produced no colouration whatever.
EXAMINATION FOR ACIDS.
The liquid had removed from it ammonium sulphydrate and hydrogen sulphide by the use of bismuth hydrate,
was then filtered and made neutral in two "tournesols" with acetic acid and ammonia.
One part of the liquid was then treated with barium chloride - no precipitate.
Thus there is an absence of the following acids: sulphuric, phosphoric, hydrofluoric and oxalic.
The absence of hydrochloric and hydrocyanic acids etc. has already been noted.
The absence of carbonic and hydrosulphuric acids etc. had already been noted at the beginning of these
experiments by the addition of hydrochloric acid.
Having saturated a sample of the original liquid with sodium carbonate and evaporated this to the point
of dryness, we took a portion of the residue and placed this in a test tube with copper filings and some
drops of pure sulphuric acid. This whole mass, brought to boiling point, gave off no odour of
hypoazotic vapour, no orange colouration appeared and some grains of morphine, when exposed to the
vapour from the tube, did not change colour; therefore, an absence of nitric acid.
These experiments, therefore, allow us to conclude, as we do, an absence in the liquid of all minerals
and all acids which the examination was deigned to detect.
THE PILLS: CHEMICAL ANALYSIS.
We again verified the purity of our reagents.
In a porcelain bowl, previously washed with distilled water, we placed four pills, which were crushed
and to which was added pure, concentrated sulphuric acid. The whole mass was heated, being continually
stirred with a glass rod. Heated to the point where all vapour had been given off. The carbon deposited
in the bowl, taken up in boiling distilled water, was subjected to the same type of testing as that
used on the liquid: no trace of metals was noted therein.
When saturated with ammonia and treated with a moderate quantity of ammonium sulphydrate, a plentiful
black precipitate was formed. The following metals were detected in the precipitate: nickel, cobalt,
iron, zinc, manganese, chromium, aluminium and also phosphates and oxalates. Although the quantity of
precipitate was plentiful in relation to the amount of the liquid used, it was too little to allow a
detailed analysis of all substances present. However, the black colouration of the precipitate could
only be due to the presence of iron, cobalt and nickel. But the fact that it dissolved rapidly in
hydrochloric acid served to demonstrate the definite presence of iron.
The liquid was filtered, hydrochloric acid added, then heated to boiling point; it was then neutralised
with ammonia, treated with ammonium carbonate and gently heated. A light cloudiness ("louche") became
visible. Left arest for half an hour, this cloudiness increased, very probably due to the presence of
lime which occurs in a large number of organic compounds.
CONTROL OF THESE TWO EXPERIMENTS.
So that no doubt could be cast on this report by the accidental introduction of extraneous matter in
the course of the lengthy procedures, the foregoing analysis had to be controlled and so it was
performed again.
Two and a half pills, divided with a platinum knife, were placed into a porcelain bowl which had been
washed in distilled water. Sulphuric acid was added to this matter and again burned. The mixture was
stirred the whole time with a glass rod which was perfectly clean. Heated, to the point where vapours
had been given off, the carbonised mass was pulverised in the bowl with an agate pestle and was burned.
Treated twice with pure hydrochloric acid, the liquid was divided into two parts. When ammonia was
tipped into the first part, a yellowish precipitate was formed. The addition of ammonia sulphydrate
formed the same black precipitate which displayed the same characteristics as in the first experiment
and demonstrated again the presence of iron.
The liquid, when filtered and treated as already discussed, produced this same cloudiness, very probably
due to the presence of lime, of which we have already spoken.
When the liquid was heated, filtered, treated with sodium phosphate, a very visible cloudiness
resulted. Therefore, magnesium was present. It is normal for pills to be rolled in magnesium carbonate
after they are made.
The liquid was filtered, evaporated to dryness and heated to red heat. The residue was dissolved in
distilled water, boiled with a light infusion of barium water and filtered. Treated with a light amount
of dilute sulphuric acid, heated to boiling point, filtered, evaporated to dryness: the residue, taken
up in a small quantity of water, produced no precipitate when treated with platinum bichlorate;
therefore, an absence of potassium.
TESTING FOR ORGANIC SUBSTANCES.
When the analysis for inorganic substances had been done, it remained to test for and identify organic
substances. In similar circumstances, usually the expert could assess the effects of poison (symptoms
and tissue lesions) and moreover, he could gather from nature various samples of the substance used
which immediately gives him a very strong suspicion about the nature of the substances. In these
circumstances, and when there is available an appropriate amount of the substances, analysis is
possible, although presenting some difficulties; and the result of the chemical analysis, combined with
the physical characteristics and the effects, can give almost complete certainty.
Here, the pills and the liquid being mixtures in nature, giving no recognisable sign of the substances
used (leaves, roots, insect remains etc.); moreover, the taste, the colour, the smell of these
substances giving no specific character (apart perhaps from the capsicum); and, besides, as there had
been no effects as no one had taken these medicines, it followed that chemical analysis alone would be
able to thrown light on the question and this analysis naturally involved methodical and detilaed
research on all the organic substances. Work which is possible on inorganic substances is hardly
available with the present state of science for organic substances. It is quite true that a general
method was proposed by M. Stas in 1845, a method that was followed by Messrs. Orfila, Devergie,
Chevalier. Lassaigne etc. But in most cases only an impure substance was obtainable which was
impossible to characterise physically, even chemically, and one had to be satisfied with various
imperfect reactions. But even assuming this work had been done, even supposing that one had been able to
obtain a subtance in a state of reasonable purity, to allow the use of reagents even in these
favourable circumstances, chemical analysis alone would only have been able to give cause for a slight
suspicion. The reactions which occur in contact with the majority of these organic substances and their
reagents, are far from being characteristic. The colour changes etc., which occur between substances
and their reagents. these same changes, I state, very often happen also between these reagents and
other organic substances.
"If one wanted our whole opinion, "said M. Galtuier, "we would place more confidence in the physical
characteristics of substances under investigation viz. smell, colour, taste etc. than in chemical
reactions such as are used in the present state of science."
GENERAL CONCLUSIONS:
From all these researches, the results are:
1) That the physical examination of the liquid gave us no indication of the nature of the substances
that it contains.
2) That the physical and microscopic examination of the pills allowed us to assume the very likely
presence of cayenne pepper.
3) That chemical analysis demonstrated the total absence of mineral substances in the liquid.
4) That chemical analysis of the pills demonstrated the presence of iron in fairly large quantities, of
magnesium and traces of lime.
5) That the discovery by chemical analysis of the organic substances contained in the mixtures under
analysis, is impossible in the present circumstances and in the present state of science.
Signed F.A.H.LARUE
Licenciate of Medicine, Professor etc.