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An instance of this kind once happened in England, and after the funeral was over the surgeons obtained the body for dissection; but as soon as the knife penetrated the muscles they resumed their power in obedience to the will, and the individual, to the astonishment of the surgeons, arose again and lived several years afterwards.

The muscles are of different sizes and forms according to their situations and the force which it is necessary for them to exert; but notwithstanding they are absolutely necessary to produce motion, yet they never move themselves; they are excited to action by the agency of some

part of the

NERVOUS SYSTEM.

Under this head is included,

First, The nerves of involuntary molion: these stimulate and excite to action all the muscles that are independent of the will, all that are concerned in digestion, circulation and respiration. These functions proceed incessantly, from the very commencement of our animal existence to the last moment of life-whether we are asleep or awake--without our being conscious of it, and without our being able to prevent it by any act of the mind. These nerves do not originate in the brain.

Second, The nerves of voluntary motion all originate in the brain, and are under the control of the will. They are the messengers which convey to the muscles the decisions of the mind; they cease to act when separated from the brain, and are evidently mere instruments of communication between the brain and the muscles.

Whenever the mind determines to act, the voluntary nerves receive an influence from the brain, and quick as lightning convey it to the appropriate muscles, which instantly contract and produce the action. Thus, if we wish to speak-the brain conveys, through the medium of the voluntary nerves, an influence (probably some kind of electric fluid) to the muscles of the tongue, throat, lips, &c., and instantly they contract, producing the requisite sounds. THIRD, The brain or phrenological nerves.

The consideration of this division of the nervous system, constitutes the science of Phrenology in its most limited sense.

FOURTH, The nerves of the five senses convey impressions to the brain from the external world: the optic nerve conveys impressions of light; the auditory nerve, of sound; the gustatory nerve, of savors; and the olfactory nerve, of odors; while the nerves of touch extend from all parts of the body and head, an infinite number of exceedingly minute. branches, conveying to the brain impressions of cold, heat, pain, and mechanical pressure.

Thus we have seen that the bones cannot move unless acted upon by the power of the muscles ; and that the muscles are incapable of acting until they are excited by the nerves; while the nerves are dependent upon the brain; and the brain is excited by the five senses; which in their turn are stimulated to action by the external world.

These three classes of organs, the bones, the muscles, and the nerves, constitute the most essential part of the human constitution. All the other systems of organs are merely auxiliary to these, and conducive to their nourishment and support. They may be divided into the

DIGESTIVE SYSTEM, that receives the food and manufactures into blood; the

ARTERIAL SYSTEM, that conveys the blood to every part of the constitution; and the

VENOUS SYSTEM, that returns it again to the lungs.

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CHAPTER II.

TEMPERAMENT_OR PROPORTION OF THE SYSTEMS,

When all the systems which compose the constitution are perfect in form, and size, and vigour, the individual may be

said to possess

A BALANCED TEMPERAMENT.

But this perfect proportion of parts is rarely found, except in the imagination of the poetical. The Apollo Belvidere, and the Venus de Medicis, and many other statues, have been executed with the intention of representing the perfection of all the parts of the human constitution combined in one subject. Shakespeare makes Hamlet représent his father as being endowed with such perfection; a constitution “whereon every god* had set his seal, to give the world assurance of a man.”

When one system of organs predominates over the rest,

* The ancients báscued that a particular Deity presided over each part of the body.

its influence may be observed in every part--producing a modification of the form, size, texture, or complexion, and varying the degree of activity and energy with which the organs of the brain perform their functions.

Each temperament is named after the system of organs, the predominance of which produces it; thus the

MUSCULAR TEMPERAMENT

exists when the muscular system is developed in a greater degree than the other systems. This temperament is known by the firmness which it imparts to the flesh, the harshness to the expression of the countenance, and the strength, to the body generally.

The oseous or bony system is frequently large, while the muscular is small, and the contrary; but since they both tend to the same result, and combine to produce strength, I shall associate the two systems under the head of muscuiar temperament.

Hercules, Ajax, Wallace, and Ethan Allen, are fine illustrations of it. We find it in the inhabitants of the rough and mountainous districts oftener than in those of the cultivated valleys and plains. It is also seen in the majority of labourers who exert themselves to operate by arduous muscular strength. Washington Irving remarks: “There seems to be races of men, as there is of animals, destined by nature to bear burdeos”: their large bony frames, and thick firm muscles admirably qualify them for usefulness where personal strength and brute force is necessary.

Women seldom are endowed with the muscular temperament, and when they are it gives them a masculine appear

Catherine, Empress of Russia, is in instance of this. But the majority of the female sex the oseous and

ance.

muscular system small; this is true of animals generally, and cannot therefore be attributed to the delicate habits of women.

NERVOUS TEMPERAMENT.

When that class of organs which constitutes the nervous system predominates, in accordance with the well established principle that size is a measure of power, (all other things being equal,) it will have an influence over the other systems in an exact proportion to its superiority in comparative size.

The Involuntary Nerves, the office of which is to excite certain muscles to action independently of the mind, will certainly have more effect if those muscles are small. The nerves do not however give strength, but only activity. The strength of the muscles depends upon their size, but their activity depends upon the nervous apparatus that excites them. · The same remarks are true of

The Voluntary Nerves; and persons of this temperament speak, walk, and perform all their actions with great rapidity. They are well adapted to situations that require great celerity, but where little muscular strength is necessary. When we consider that the voluntary nerves act upon muscles in obedience to the organs of the brain, it is plain that the smaller the muscles are, compared to the exciting power, the more rapid must be their action. And this is actually the case—when the bones and muscles are small, and the nervous system powerful, the limbs and the features (which are composed principally of muscles) move quickly, and are easily excited to sudden actions.

The Brain or Phrenological Nerves also act more powerfully when the muscular system is comparatively small.

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