Charles Bell

Second Part of the Paper on the Nerves of the Orbit

In these papers I endeavour, to the utmost of my power, to distinguish between the facts which I am able to substantiate, and the hypothesis by which I have been directed in my inquiries. I hope that the importance of the facts may give some bias in favour of that mode of reasoning by which they have been discovered, and an additional interest to anatomical studies. In my endeavour to arrange the nerves of the orbit, I encounter, in the first step, all the difficulties of my subject; for although there be only nine nerves properly enumerated as proceeding from the brain, six of these go to the eye; the second, third, fourth, part of the fifth, sixth, and seventh, go into the orbit, and may be said to be concentrated into a space no larger than a nut-shell.

Of the Nerves Which Associate the Muscles of the Chest, in the Actions of Breathing, Speaking, and Expression. Being a Continuation of the Paper on the Structure and Functions of the Nerves

In a former paper an examination was made of the nerves of the face; that part of the system was taken, as proving in a manner the least liable to exception, that two sets of nerves, hitherto undistinguished, possessed distinct powers; and that very different effects were produced when the muscles and integuments were deprived of the controuling influence of the one or of the other of these nerves. In that paper it was shown, that parts remote in situation, were yet united by the closest sympathy with the lungs. That by a division of one nerve, these organs could be severed from the other parts of the apparatus of respiration; and though rendered dead to the influence of the heart and lungs, were yet possessed of their other properties, such as sensibility and voluntary motion. In the present paper it is proposed to prosecute this subject, by tracing the nerves which influence the motions of the trunk of the body in respiration, and to subject them to a similar enquiry.

XIV. Of the organs of the human voice

The organs of the Human Voice are related to many interesting inquiries in science and philology; and yet it is remarkable that this subject has hitherto occupied no place in the Transactions of the Society. In a matter so open to observation as the anatomy of the throat, there can, indeed, be no new parts discovered; but it will be easy to show that their actions have been very negligently treated. It will not, I hope, lessen the interest of the inquiry, that I acknowledge having an ulterior object in it. The nerves distributed to the neck and throat are the most intricate of all. That they have not been unravelled, and distinct uses assigned to each, is owing to the complexity and the numerous associations of the organs to which they tend. When we shall have seen the necessity of combination among the various parts, for producing the simplest effort of the voice, we shall find a reason for these numerous nerves, and for their seeming irregularities.

On the Nervous System

Twenty years have passed since the Society honoured me by printing my first paper on the functions of the nervous system. It is thirty years since I circulated a short essay, in which the idea of the new principle which has guided me in my inquiries into this subject was pointed out. The Society will acknowledge that since that time, investigations into the nervous system have been prosecuted with a success strongly in contrast with that attending the inquiries during the long period of some hundred years, in which a false hypothesis had satisfied the minds of the medical profession, and chained down physiologists in inactivity. In 1821 I had made so much progress in these investigations, that I was encouraged to present my first paper to the Society, as no longer the expression of mere opinions founded on experiments too delicate to be generally appreciated, but demonstrations of substantial facts, easily proved to be correct, and such as the Society has always sought to encourage. After the principle had been once established by anatomy and experiment, that the nerves possess distinct functions in correspondence with their origins from the brain and spinal marrow, time and opportunity were alone wanting for collecting the pathological facts which were to give importance to the observations in these early papers. Those facts I am now desirous of placing before the Society, to complete the subject as far as regards my own labours.

Continuation of the Paper on the Relations between the Nerves of Motion and of Sensation, and the Brain; More Particularly on the Structure of the Medulla oblongata and the Spinal Marrow

In this paper it will be necessary to enter on minute details of the anatomy; but they regard a subject hitherto untouched, although essential to the comprehension of the nervous system, without which, indeed, it could not be said that we had a know ledge of the nerves as a system. The author has advanced, by slow and laborious researches, from observing the general arrangement of the nerves as they lie in the body, to the investigation of particular nerves and their endowments; and, finally, to the examination of these parts in the centre of the system, the brain and spinal marrow, which enables him to assign the reason of that perfect symmetry which reigns through the whole.

On the Functions of Some Parts of the Brain, and on the Relations between the Brain and Nerves of Motion and Sensation

The difficulties which attend the investigation of the structure and functions of the brain are shown by the ineffective labours of two thousand years; and the first endeavour of the author is to remove the idea of presumption that attaches to the very title of this paper. Perhaps the enumeration of some of the sources of error which have retarded discovery may be the best introduction and apology. The first impediment to success is in the nature of the inquiry, since extraordinary and contradictory results must be expected from experimenting on an organ so fine as that must be which ministers to sensibility and motion, and which is subject to change on every impression conveyed through the senses. This remarkable susceptibility is exemplified in what we often witness; extraordinary results, such as violent convulsions and excruciating pain, from causes which appear quite inadequate. For example, the presence of a minute spicula of bone which has penetrated to the brain, will at one time be attended with no consequence at all; at another it will occasion a deep coma, or loss both of sensibility and motion. Nay, symptoms apparently as formidable will be produced by slight irritation on remote nerves. Seeing these contradictory effects, is it reasonable to expect constant and satisfactory results from experiments in which deep wounds are inflicted on the brain of animals, or portions of it torn away ?