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the occurrence of sensation by its action
upon the connection between the mind and the brain. The pain of a wound received in battle is often unfelt until the excitement of the battle is over, and the aching of a tooth is often stopped by the excitement consequent upon going to the dentist to have it extracted.
3. In these cases the cause of the pain is acting all the time upon the nervous extremity, the trunk of the nerve is capable of transmitting the impression, and the brain is doubtless capable of receiving it, but the mind is so intensely occupied with other things that it takes no notice of the messages sent up from the nerves. Thus the mind may at times rise superior to physical suffering, and withdraw itself, to a certain extent, from bodily influences. We witness this in the exultation with which the savage at the stake sings his deathsongs, and the Christian heroism6 with which martyrs have met death amid the direst tortures of the body. It is on the same principle that the man of stubborn and resolute will is often enabled to resist pain, while the feeble-minded and the irresolute are overcome by it.
II. NERVOUS PARALYSIS. 1. Sometimes the nerves of expression which extend over the face are paralyzed? on one side only. The result is, that while the individual can masticated equally well on both sides, he can laugh, and cry, and frown only on one side, and he can not close the eye on the side affected. Thus, if the nerve of expression covering the left side of the face be paralyzed, the left eye can not be closed by any effort, and the left side of the face will be wholly devoid of expression. This nerve of expression is often paralyzed by itself, the other nerves in the neighborhood, both nerves of sensation and of motion, being entirely unaffected. This nerve has been called the respiratory nerve of the face, because it controls motions which are connected with the movements of respiration.9
2. If we observe how the various passions and emotions are expressed, we shall see that there is a natural association between the muscles of the face and those of the chest in this expression. This is very obvious in laughing and in veeping. But this association can be effected only through nervous connections, and these connections in this case are very extensive and intimate. When the nerve of expression, or the facial respiratory nerve, is paralyzed, all the motions of the face connected with the respiration are absent. Though
the individual may sob in weeping, or send forth the rapid and excessive expirations of laughter, yet the face on the side where the nerve is paralyzed will be perfectly quiescent.10 So, too, those movements of the nostrils which are sometimes used in expression can not be performed. Sneezing can not be done on the affected side, nor can the individual whistle, because a branch of this nerve goes to the muscles at the corner of the mouth, which are therefore disabled. Sir Charles Bell, in cutting a tumor from before the ear of a coachman, divided this branch of the nerve. Shortly after, the man thanked him for curing him of a formidable disease, but complained that he could no longer whistle to his horses.
3. Another singular case of paralysis narrated by Sir Charles Bell is that of a mother who was seized with a paralysis, in which there was a loss of muscular power on one side, and a loss of sensibility on the other. She could hold her child with the arm of the side which retained its power of motion, but had lost its sensibility. But she could do it only when she was looking at it. She could not feel her child on the arm, and therefore, when her attention was drawn to any thing else, and she ceased to have her eyes fixed on the child, the muscles, having no overseer, as we may say, to keep them at work, were relaxed at once, and the child would fall from her
III. NO FEELING IN THE NERVES OF MOTION, IN THE
BRAIN, OR IN THE HEART. 1. It was formerly supposed that a nerve must, of course, have an exquisitell sensibility.12 But there is no sensibility in nerves devoted to motion, as we have already seen. ther is there any in the brain itself, but only in its enveloping membranes. Portions of the brain may be cut off without producing any pain. The heart, too, is insensible to touch. A case proving this fell under the observation of Harvey, the discoverer of the circulation of the blood. A
nobleman, from an injury received in a fall, had a large abscess13 on the chest, which occasioned such a destruction of the parts as to leave the lungs and heart exposed. Charles the First, on hearing of the case, desired Harvey to see it.
2. “When," says Harvey, "I had paid my respects to this young nobleman, and conveyed to him the king's request, he inade no concealment, but exposed the left side of his breast, when I saw a cavity into which I could introduce my fingers and thumb. Astonished with the novelty, again and again
I explored the wound; and first, marveling at the extraordinary nature of the case, I set about the examination of the heart. Taking it in one hand, and placing my finger on the wrist, I satisfied myself that it was indeed the heart which I grasped. I then brought him to the king, that he might behold and touch so extraordinary a thing, and that he might perceive, as I did, that, unless when we touched the outer
' skin, or when he saw our fingers in the cavity, this young gentleman knew not that we touched his heart !”
3. This absence of sensibility in the heart is not because it is not well endowed with nerves. It is well endowed, not with the nerves of ordinary sensation, but with those which are devoted to another purpose. They are nerves of sympathy, which notify the condition of the heart to the seats of involuntary motion in the spinal marrow, and which also establish a connection with every pårt of the body, making the heart to be so easily affected by motion, by disease, and by every passing emotion in the mind. IV. THE REUNION AND HEALING OF SEVERED NERVES.
1. There are some wonderful facts in regard to the reunion and healing of severed nerves. It has been seen that if a nerve trunk be divided, all communication between the part which it supplies with branches and the brain is cut off. But the two cut ends of the trunk can grow together, and the communication can thus be more or less restored. This must appear to us passing wonderful when we consider that each nerve trunk is made up of a great number of separate fibres, each one of which goes from its origin in the nervous centre to its destination by itself. For these nerves to heal without causing confusion, it is essentially necessary that each little fibre should unite, at its cut end, with its corresponding end, and not with the end of some other fibre. For example, if the nerves distributed to the hand were cut, it would not do to have the fibres which go to the thumb unite with those which go to a finger.
2. The difficulty of accurate union would seem to us to be still further increased by the fact that, in the same bundle of nerve fibres, the different kinds, those of motion and those of sensation, are bound up together, and we know that it would not do for a nerve of motion to unite with a nerve of sensation. Yet we learn, by repeated experiments, that the most accurate union of severed nerves is often effected, each minute fibre, in whatever position it may be placed, apparently
seeking out and uniting with its severed part, so that eventually the communication of impressions is as perfect as before.
3. But a still more wonderful fact is exhibited in the union of parts which did not originally belong together, as, for example, when a piece of skin is dissected from the forehead, and is twisted down so as to be made to grow on to the nose, to supply a deficiency there. Here entirely new relations are established between the nerves of the divided parts, and, as we should expect, there is confusion in the sensations. The patient at first, whenever the new part of the nose is touched, refers the sensation to the forehead. But this confusion of the sensations is after a while removed. And it is curious to observe, that while the old nervous connections are breaking up, and the new ones becoming established, there is an interval of partial, sometimes entire insensibility in the part. How these new relations can be established consistently with the known arrangement of the fibres in the nerve bundles is a mystery. Physiologists do not attempt to explain it; they merely attribute all such processes to what they call the “Healing Power of Nature.” 1 TĚXT'-ŪRES, different parts or layers, each ? PĂB'-A-LĪZED, affected with the palsy; be. 2 MŪ'-fous MĚM'-BRĀNE, a thin and slimy 8 MĂs'-TI-CATE, chew; grind with the teeth.
9 RES-PI-RĀ'-TION, the act of breathing. 3 TŪ'-MOR, a swelling.
10 QUI-ES'-CENT, in a state of repose. 4 EF-FŪ'-$10N, a pouring out from the proper 11 Ěx-'QUI-SĪTE, peculiarly delicate; keenly
[feeling 5 RŪPT'-ŪRE, a breaking.
12 SEN-SI-BĚL'-I-TY, acuteness or delicacy of 6 HĚR'-0-1$m, the spirit and conduct of a 13 ĂB'-SCESS, a swelling containing a whitish hero; fortitude.
matter called pus.
likened to a web that is woven.
LES. VII.-INTEMPERANCE, THE PRIME MINISTER OF DEATH.
1. DEATH, the king of terrors, was determined to choose a prime minister ;? and his pale courtiers, the ghastly: train of diseases, were all summoned to attend, when each preferred his claim to the honor of this illustrious office. Fever urged the numbers he destroyed; cold Palsy set forth his pretensions by shaking all his limbs; and Dropsy, by his swelled, unwieldy carcass; Gout hobbled up, and alleged his great power in racking every joint; and Asthma's inability to speak was a strong though silent argument in favor of his claim. Colic and Rheumatism pleaded their violence; Plague his rapid progress in destruction; and Consumption, though slow, insisted that he was sure.
2. In the midst of this contention, the court was disturbed
by the noise of music, dancing, feasting, and revelry, when immediately entered a lady, with a confident air and a flushed countenance, attended by a troop of cooks and bacchanals:6 her name was INTEMPERANCE. She waved her hand, and thus addressed the crowd of diseases: “Give way, ye sickly band of pretenders, nor dare to vie with my superior merits in the service of this great monarch. Am not I your parent? Do ye not derive the power of shortening human life almost wholly from me?_Who, then, so fit as myself for this important office ?”. The grisly monarch grinned a smile of approbation, placed her at his right hand, and she immediately became his principal favorite and prime minister.-ANONY
1 PRIME MĨN'-IS-TER, a chief officer in civil 4 PRE-FER'RED, put forward; urged. affairs.
5 RÆV'-EL-BY, carousing with noisy merri. 2 COURT'-IER, an attendant who flatters to ment. please.
6 BĂ€'-CHA-NALS, those who indulge in 3 Ghåst'-LY, death-like; very pale; hideous. drunken revels.
LESSON VIII.-"LOOK NOT UPON THE WINE.”
Is red within the cup!
Her tempting bēakerl up!
A spell of madness lurks below.
And merry on the brain;
And dulls the tooth of pain.
A stinging serpent, unseen, sleeps.
Its coolness change to thirst;
A sleepless worm is nursed.
That does not carry food for him.
And spill its purple wine;
Let not its curse be thine.
Are in those rosy depths below. WILLIS. 1 BRAK'-ER, a drinking-cup or glass. 13 SLŪG'-GISH, having little motion. 2 SPELL, a charm consisting of words of hid-4 BRŤM'-MING, full to the very brim.