Lectures on the nervous system and its diseases / by Marshall Hall.

  • Hall, Marshall, 1790-1857.
Date:
1836
Catalogue details

Licence: Public Domain Mark

Credit: Lectures on the nervous system and its diseases / by Marshall Hall. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    cooks, by means of a knife, which divided the second or third vertebra. 52. The head being placed upon the table for observa- tion, it was first remarked that the mouth opened and shut, and that the submaxillary integuments descended and as- cended, alternately, from time to time, replacing the acts of respiration. 1 touched the eye or eye-lid with a probe. It was immediately closed: the other eye closed simulta- neously. I then touched the nostril with a probe. The mouth was immediately opened widely, and the submaxillary membranes descended. This effect was especially induced on touching the nasal fringes situated just within the anterior part of the maxilla. I passed the probe up the trachea and touched the larynx. This was immediately followed by a forcible convulsive contraction of the muscles annexed to it. Having made and repeated these observations, I gently with- drew the medulla and brain. All the phenomena ceased from that moment. The eye, the nostrils, the larynx, were stimulated, but no movement followed. 53. The next observations were made upon the other parts of the animal. The limbs, the tail, were stimulated by a pointed instrument or a lighted taper. They were im- mediately moved with rapidity. The sphincter was perfectly circular and closed; it was contracted still more forcibly on the application of a stimulus. The limbs and the tail pos- sessed a certain degree of firmness or tone, recoiled on being drawn from their position, and moved with energy on the application of the stimulus. On withdrawing the spinal marrow gently out of its canal, all these phenomena ceased. The limbs were no longer obedient to stimuli, and became perfectly flaccid, having lost all their resilience. The sphinc- ter lost its circular form and its contracted state, becoming lax, flaccid, and shapeless. The tail was flaccid, and un- moved on the application of stimuli. 54. This experiment affords evidence of many important facts in physiology. It proves that the presence of the me- c2