From Clouds to the Brain. Celine Cherici
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Название: From Clouds to the Brain
Автор: Celine Cherici
Издательство: John Wiley & Sons Limited
Жанр: Физика
isbn: 9781119779506
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I repeated on the corpse of a beheaded criminal the observations I had made on the head and torso of an ox. I established an arc from the spinal cord to the muscles: a prepared frog was part of this arc. I always got strong contractions without the help of the battery, without the slightest influence of metals. I have observed proportionately the same result on naturally dead men. [ALD 04, pp. 9–10, author’s translation]
Then he experimented on:
[…] the head of a dog, passing the current of a strong battery: this single contact excited truly frightening convulsions. The mouth opened, the teeth clattered, the eyes rolled in their sockets; and if reason did not stop the struck imagining, one would almost believe that the animal had returned to suffering and life. [ALD 04, pp. 9–10, author’s translation]
These descriptions, worthy of horror novels, contributed to the imagining of the mad scientist who creates life from a subject presumed dead. In November 1803, in Mainz, the leader of a group of bandits, named Schinderbannes, was beheaded, along with 19 of his accomplices. The town’s doctors hastened to recover the bodies in order to submit them to the galvanic experiment. Nevertheless, the delays in the arrival of the bodies did not allow them to experiment on more than four torture victims [FIG 67, v. 1, p. 650]. They derived the following physiological principles from it:
That the muscular contractions which were obtained by means of the Voltaic pile on recently killed individuals reproduced mechanically, in a most perfect manner, the movements performed during life; That the action of the battery was all the more sensitive, the more precisely the electric current followed the direction of the nerves; That the muscles subjected during life to the influence of the will obeyed, better than those which are independent of it, the electric agent. [MAN 63, p. 192, author’s translation]
At least two remarks can be made: the expression “mechanically reproduced the movements of life” shows the aspect of a medicine marked by the human automaton model. Furthermore, the idea that the muscles subject to consciousness were those that “obeyed” electricity best was not insignificant. This point, in apparent contradiction to the first, underlines the medico-philosophical significance of this research: do feelings and willpower persist for some time after beheading? [TIL 15]
On January 17, 1803, in London, in front of members of the Royal College of Surgery, Aldini experimented on the body of Georges Forster, a criminal hanged for the murders of his wife and children.
Figure 1.2. Aldini tests the muscular reactions of a human head and then of the whole body [ALD 04, slide 4, fig. 1-6]
By using the Voltaic pile, it led to waves of contractions and convulsions, marking in a first series of experiments, the face of the grinning murderer:
The head was first subjected to the action of galvanism, by means of a pile of 100 silver and zinc plates: two metal wires, one from the base and the other from the top of the pile, came to the inside of the two ears, which were moistened with salt water. I first saw strong contractions in all the face muscles, which were contorted so irregularly that they imitated the most awful faces. The action of the eyelids was very marked, although less sensitive in the human head than in the ox’s head. [ALD 04, p. 70, author’s translation]
After animating his face, the scientist plugged a cable into the ear and another directly into the rectum. Forster’s body then began to move frantically, in a disarticulated manner. You can imagine the impression made on the assembly. His experiments were driven by a genuine scientific curiosity on Aldini’s part and could not be reduced to a mere spectacle. The latter, on the other hand, played an important role in the dissemination of knowledge. For example, on the subject of sensitivity or insensitivity of the brain, he carried out animal electrophysiology to show that with: “[…] an iron plate, or by touching them with silver nitrate: then the live animals feel the most pain, as when they are inflamed” [ALD 04, p. 87, author’s translation]. Moreover, these post-mortem experiments on whole corpses enabled a deeper understanding of the respective places of the heart and the brain in the dying process. It was also an opportunity to explore the technical possibilities of restarting the heartbeat beyond the cessation of the pulse. Experiments on the galvanization of the heart provoked exciting debates in electrophysiology in the early 19th Century:
This muscle2 which, according to Haller’s principles, is the first to receive life and the last to lose it, follows a different law when subjected to the action of galvanism. [ALD 04, pp. 99–100, author’s translation]
Aldini explored the influence of galvanism on the heart while experimenting with direct galvanization of the isolated brain. The challenge was to determine which of the two organs could be considered as a physiological center in the dying process and therefore whether galvanization could have the most important action:
Then Dr. Mondini, with all his skill, tried to separate in the brain the medullary substance, the corpus callosum, the striated bodies, the layers of the optic nerves, and the cerebellum. All these parts were successively brought into an arc, and the results of the experiments previously carried out on the bodies of other criminals were confirmed with full success. [ALD 04, p. 82, author’s translation]
Volta considered the heart to be an insensitive organ, whereas Humboldt and Grapengiesser claimed, on the contrary, that it reacted strongly to galvanic stimulus. Thus, within the framework of controversial experiments, a field of medical observations opened up on the action of galvanism on the cardiac organ, the cessation of which was the first symptom, at least until 1940, of the process of dying. The polemics on its status played a dual role: on the one hand, the experiments on its state, after the passage to immobility and unconsciousness, enabling the passage from a resurrection envisaged medically to the techniques of eanimation; on the other hand, they played a fundamental role in the electrical imagining which developed around questions on life, death and the porosity of these two states:
What was my surprise, in carrying out this kind of research, to recognize that the heart, despite all the assertions made to date about its insensitivity to galvanism, is of all the organs, the one that retains its excitability the longest under the influence of this agent, and therefore occupies the first place in relation to the duration of galvanic excitability, […]. [NYS 02, p. 8, author’s translation]
Thus, Nysten (1771–1818)3 conducted galvanic experiments on dogs freshly poisoned with opium. He used a vertical Volta device, consisting of 38 zinc discs, 3 coins and 38 cloths soaked in a solution of ammonia muriate:
As a result, this substance does not annihilate the galvanic excitability; but I did not pay enough attention to this kind of experiment to dare to ensure that it does not diminish the energy of this property […]. [NYS 02, p. 14, author’s translation]
In order to test the excitability of the heart in a post-mortem situation, he tried to recover4 the bodies of convicts just after their execution. Thus he obtained the body of a 27-year-old man, considered to be of a hot-headed temperament due to his having committed a criminal act and having just been beheaded:
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