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"organ, that it is the organ of voice and of speech as much "as of taste and exquisite feeling. It would, indeed, be "matter of surprise if the same nerve served for the action "of gnawing and feeding in the lower animals of simple "structure, and also for the governance of those complicated "operations which serve to interpret the wants and senti"ments of men."-403.

This, it will be readily admitted, is the purely phrenological doctrine applied to other parts of the nervous system. All the parts of the brain, from the similarity of appearance, have, like all the nerves, been supposed to have only one function, and as no physiological fact could ever be reconciled to this supposition, all inquiry into the nervous system was deemed idle and unprofitable.

But when we admit that one part of the brain, like one nerve, can only execute one function, and that for every new mental faculty added as we rise in the scale of creation, there must be an addition of another part of the brain, then our inquiry becomes interesting, for we instantly find an explanation of the phenomena. There is a nerve of respiration, a nerve of manducation, of the voice, and of feeling, and of taste in the mouth. In like manner we must admit an organ of benevolence, of veneration, of self-esteem, of amativeness, and of love of offspring, because each of these is distinct from and added to the other. If the whole brain served for all these, then it is impossible that man could have mental faculties different in kind from those of the lower animals, or that one of the latter could possess faculties which another does not, although all have brains, and in all the brain is avowedly the organ of mind.

Mr B., taking comparative anatomy for a guide, divides the nerves, by an easy and natural method, into two parts or systems, the one simple and uniform, the other irregular and complex. Wherever an animal is endowed with mere sensation and locomotion, and has no central organ of circulation, and no organ of respiration but what is generally diffused over the surface, the nerves are extremely simple, and

consist of two cords running, in the length of the body, with branches going laterally. Wherever organs are superadded to these, as the animal advances in the scale of existence, the nerves of the irregular or complex system are superadded to the other in exact proportion to the additional functions performed. Thus, the simple and uniform system is to be observed in the human body as well as in the leech or worm, only it is obscured by the variety of superadded nerves proportioned to the additional functions performed.

The nerves of the spine, the tenth or sub-occipital, and the fifth pair, constitute this original, uniform, and symmetrical system. All these arise in the same way,-all go out laterally, all are exquisitely sensible,-so much so, that nerves of the irregular class are easily distinguished by their greatly less degree of sensibility. Besides, the latter do not arise by double roots, and have no ganglia on their origins,-they come off from the medulla oblongata, and upper part of the spinal marrow, and these are they which give the appearance of confusion to the dissection, because they cross the others.

The respiratory nerves in man are, 1st, the eighth pair, or par vagum, which serves to associate the larynx, heart, lungs, and stomach. That the stomach is so associated is evident from what takes place during vomiting and hiccough. These organs are supplied with other nerves for their other functions.

2d, The portio dura, which connects the motions of the lips, nostrils, and face, with the respiratory motion of the chest. By the division of this nerve this connexion is lost.

3d, Spinal accessory, which associates the muscles of the neck and shoulder in respiration, and which, when cut, leaves these muscles incapable of acting harmoniously with those of the chest, although, from being plentifully supplied with other nerves, they are still capable of voluntary motion. Thus, shewing the plan of nature.

4th, Phrenic, which associates the diaphragm, and which is the only one previously known as a respiratory nerve.

5th, What Mr B. calls the "external respiratory nerve,"

in opposition to the former as the "internal," to which it has a remarkable resemblance, which has been overlooked. It has a similar origin, and is connected with the phrenic, and goes on the outside of the ribs to muscles, which are already plentifully supplied with nerves for their other functions.

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Mr Bell then examines in detail the nerves of the face, and clearly proves, "that the two sets of nerves, hitherto sup"posed to be similar, differ in structure, sensibility, and "function." He begins by those of the face, because, happily for our present object, the nerves which, in other "parts of the frame, are bound together for the convenience of "distribution to remote parts, are here distinct, and run apart "from each other until they meet at their extremities,” and are "exposed in a manner which courts inquiry." So that the organs of the brain are not the only ones in the body which are so much "bound together" as to make it impossible to point out their exact limits. The nerves going to the extremities have now been proved to consist of two sets of fibres, one for sensation, and another for motion, although they are undistinguishably blended and enclosed in a common sheath.

In following the distribution of the two nerves which supply the face, viz., the portio dura and the fifth pair, says Mr B., "unbiassed by theory or opinion, we should be "forced to conclude, that the portio dura alone is not suffi"cient to supply any one part with nervous power, for every "one of its branches is joined by divisions of the fifth. "The questions then naturally arise, Whether these nerves "perform the same functions? Whether they furnish a "double supply of the same property or endowment, or "whether they do not perform different offices ?" To settle these points, he instituted many conclusive experiments upon the lower animals.'

On dividing the portio dura alone on one side, when the animal was panting and forcibly dilating its nostrils, the motion of the nostril of the same side instantly ceased, and the side of the face remained at rest, and perfectly placid, during

the highest excitement of the other parts of the respiratory organs, while the opposite side and nostril still acted in unison with the chest. Cutting the nerve caused no sign of pain, and the animal was able to eat without the slightest impediment, so that voluntary motion was not lost; on dividing the superior maxillary branch of the fifth pair, when the animal was in the same state of hurried respiration, acute pain was occasioned; the nostril continued to expand regularly in time with other respiratory parts, but the side of the lip was observed to hang low, and towards the other side. The same branch of the opposite side was then cut, but the animal had lost the power of elevating and projecting the lip, as in gathering food, and opened his lips only by pressing the mouth against the ground.

When the portio dura of one side was cut, and ammonia presented to the nose, the same side remained quite relaxed, but the other was curled up with the peculiar expression of sneezing. In the same way, smiling, laughing, &c., evidently depend on this nerve. The slightest touch on the portio dura convulsed the muscles of the face, but caused no pain. The reverse was the case with the fifth; touching it gave great pain, but there was more difficulty in exciting the muscles. The former is proved to be the nerve of expression.

It was suggested to Mr Bell, as an objection to his principles, that the trunk of the elephant being hollow, and connected with respiration as well as sensation, it should have two nerves, whereas Cuvier states it to have only one. But having been favoured by Mr H. Mayo with an opportunity of dissecting the trunk of a young elephant, Mr B. had no difficulty in finding two nerves, "both of great size," being continuations from the fifth and seventh pairs.

These experiments of Mr Bell are of great interest to the phrenologist, and to the physician, and their accuracy has been nearly established by those of Majendie in Paris, and Mr Schaw in London. We cannot at present proceed to the examination of Mr B.'s second paper, but we shall take oc

casion to recur to it. He has the merit of having first demonstrated the difference of function performed by different sets of nerves, in opposition to the opinions of some eminent physiologists, who tell us that the different nerves resemble the different parts of a broken magnet, so exactly, that any one could easily supply the place of another. He has also the merit of having applied a principle, which is likely soon to lead to results of the greatest importance, and to place the physiology of the nerves on a level with that of the best known organs of the body. He has the merit, in short, of having done for the physiology of the nerves, what Dr Gall has the merit of having done for the physiology of the brain. Neither was the first to conceive that different nerves or different parts of the brain must have peculiar functions, but both were the first to demonstrate the facts.

To Majendie we are also much indebted for the zeal with which he continues to prosecute his physiological inquiries, and to unfold new views. He, as well as Mr Bell, is entitled to the merit of having discovered the existence of two sets of fibres in the spinal nerves, for he was not aware of Mr Bell's experiments when he published his own.

ARTICLE VI.

DIALOGUE BETWEEN A PHILOSOPHER OF THE OLD SCHOOL AND A PHRENOLOGIST.

Phil. Do you believe in Phrenology?

Phren. Yes, I do! Do you not believe in it?
Phil. No indeed. It is most ridiculous nonsense.

Phren. How do you know? Have you studied it?

Phil. Not I. It is too absurd to merit a moment's attention. Phren. In saying so, do you not resemble a person ignorant of geometry, declaring that he does not believe in Euclid's demonstrations?

E