6 November 1857
(Continuation of the report of Mr. Larue)
8 October 1857.
(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.
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.
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.
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.
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."
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.
Licenciate of Medicine, Professor etc.