Gentlemen,—The Academy had formed a commission composed of MM. Sanson, Guèneau de Mussy, Breschet, Roux, and Dizè, to make known the results of a process presented by M. Gannal, having for its object the preservation of dead bodies destined for dissection.
Our honourable colleague, M. Breschet, presented, in a provisionary report, the experiments which had been made, and the success obtained by M. Gannal.
But the commission having expressed a desire to give more development to trials which, after the important results already obtained, deserved to fix the attention of the Academy, it proposed to him to multiply, to vary the experiments, to extend them a longer time upon a greater number of subjects.
But trials directed in this spirit, exact expenses; the commission did not think it just to impose them upon the author of the process, who had already multiplied expenses; in consequence it proposed to the Academy to demand an indemnity of government for expenses already made, and for the continuance of experiments, without any prejudice to the recompense that M. Gannal would have a right to claim.
The Academy seconded the wishes of the commission; it obtained from the minister of public instruction the sum necessary for covering all expenses made, and for those to be made in the continuance of the experiments.
M Gannal made a series of preliminary experiments, which served him as so many starting points on the road to the discovery of the means of preserving animal matters; these labours subsequently conducted to the research of an antiseptic sufficiently powerful, which unites to the property of preserving bodies, that of not altering the organic tissues, and not too much weakening their natural colours, so important to anatomical demonstrations.
We shall cite the most important experiments, so that you may be able to appreciate the process which is proposed.
In the first place, acids in general modify the consistence of animal matters; they produce disorganization in proportion to their concentration; some diluted acids, for example, nitric acid at five degrees, may serve when it is necessary to study the nervous system, but then the bones lose their saline particles and are reduced to their organic frame; the muscles are discolored and faded, as well as the viscera; the nerves alone remain of a very remarkable mother-of-pearl whiteness.
Arsenious acid preserves bodies very well, but a single subject would require a killogram! Although the medical journals having spoken of a process discovered by Dr. Tranchini, of Naples, the commission judged it expedient to invite M. Gannal to repeat this experiment; a subject was injected with a killogram of arsenious acid and ten quarts of water; this subject examined by your commission, presented all the characters of a good preservation; but, on one hand, this process has been for a long time known, and on the other hand, the employment of it presents so many dangers, that in case of its success your commission would feel themselves obliged to proscribe it; effectually, when twenty subjects were under dissection, there would be twenty killograms of this poisonous substance at the disposition of the public.
Concentrated acetic acid preserves meats, but dries them. This same acid diluted retards putrefaction, but softens the bones, as well as the muscles, which are discolored by its action.