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HERE the free spirit of mankind at length
Throws its last fetters off; and who shall place
A limit to the giant's unchained strength,
Or curb his swiftness in the forward race.
For, like the comet's way through infinite space,
Stretches the long untravell'd path of light
Into the depths of ages: we may trace,
Afar, the brightening glory of its flight,
Till the receding rays are lost to human sight.

Europe is given a prey to sterner fates,
And writhes in shackles; strong the arms that chain
To earth her struggling multitude of states;
She too is strong, and might not chafe in vain
Against them, but shake off the vampyre train
That batten on her blood, and break their net.
Yes, she shall look on brighter days, and gain
The meed of worthier deeds; the moment set
To rescue and raise up, draws near-but is not yet.
But thou, my country, thou shalt never fall,
But with thy children-thy maternal care,
Thy lavish love, thy blessings shower'd on all--
These are thy fetters-seas and stormy air
Are the wide barrier of thy borders, where
Among thy gallant sons that guard thee well,
Thou laugh'st at enemies: who shall then declare ⚫
The date of thy deep-founded strength, or tell
How happy, in thy lap, the sons of men shall dwell.

BRYANT

22*

258

STRUCTURE OF THE HUMAN BODY.

LESSON 117.

Structure of the Human Body.

Car'tilage, gristle. Ad'ipose, fatty.

Ten'dons, hard, insensible cords, by means of which muscular fibres are attached to bones.

DR. HUNTER gives the following beautiful representation of the structure of the human body, with reference to all the wants and requisites of such a being as man, in answer to a supposed objector, who asks why a more simple, less delicate, and less expansive frame had not been adopted. First, says he, the mind, the thinking, immaterial agent, must be provided with a place of immediate residence, which shall have all the requisites for the union of spirit and body; accordingly, she is provided with the brain, where she dwells as governor and superintendent of the whole fabric. In the next place, as she is to hold a correspondence with all the material beings around her, she must be supplied with organs fitted to receive the different kinds of impression which they will make. In fact, therefore, we see that she is provided with the organs of sense, as we call them; the eye is adapted to light; the ear to sound; the nose to smell; the mouth to taste; and the skin to touch. Further, she must be furnished with organs of communication between herself in the brain, and those organs of sense; to give her information of all the impressions that are made upon them; and she must have organs between herself in the brain, and every other part of the body fitted to convey her commands and influence over the whole. For these purposes the nerves are actually given. They are soft white chords which rise from the brain, the immediate residence of the mind, and disperse themselves, in branches, through all parts of the body. They convey all the different kinds of sensations to the mind in the brain; and likewise carry out of thence all her commands to the other parts of the body. They are intended to be occasional monitors against all such impressions as might endanger the well-being of the whole, or of any particular part; which vindicates the Creator of all things in having actually subjected us to those many disagreeable and painful sensations which we are exposed to from a thou sand accidents in life.

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The mind, in this corporeal system, must be endued with the power of moving from place to place; that she may have intercourse with a variety of objects; that she may fly from such as are disagreeable, dangerous, or hurtful; and pursue such as are pleasant and useful to her. And accordingly she is furnished with limbs, with muscles and tendons, the instruments of motion, which are found in every part of the fabric where motion is necessary. But to support, to give firmness and shape to the fabric; to keep the softer parts in their proper places; to give fixed points for, and the proper directions to, its motions, as well as to protect some of the more important and tender organs from external injuries, there must be some firm prop-work interwoven through the whole. And, in fact, for such purposes the bones are given. The prop-work is not made with one rigid fabric, for that would prevent motion. Therefore there are a number of bones. These pieces must all be firmly bound together, to prevent their dislocation. And this end is perfectly well answered by the ligaments. The extremities of these bony pieces, where they move and rub one upon another, must have smooth and slippery surfaces for easy motion. This is most happily provided for, by the cartilages and mucus of the joints. The interstices of all these parts must be filled up with some soft and ductile matter, which shall keep them in their places, unite them, and at the same time allow them to move a little upon one another; these purposes are answered by the cellular membrane, or adipose substance. There must be an outward covering over the whole apparatus, both to give it compactness, and to defend it from a thousand injuries; which, in fact, are the very purposes of the skin and other integuments.

QUESTIONS.-1. How does the soul correspond with material beings? 2. What are the nerves, and their use? 3. Of what use are the bones? 4. The ligaments, cartilages, and mucus? 5. Cellular membrane? 6. Skin and other integuments ?

260

STRUCTURE OF THE HUMAN BODY.

LESSON 118.

Structure of the Human Body (continued.)

Secretion, the process by which various fluids are separated from the blood by means of the glands. Vas'cular, full of vessels.

THE mind being formed for society and intercourse with beings of her own kind, she must be endued with powers of expressing and communicating her thoughts by some sensible marks or signs, which shall be both easy to herself, and admit of great variety; and accordingly she is provided with the organs and the faculty of speech, by which she can throw out signs with amazing facility, and vary them without end. Thus we have built up an animal body which would seem to be pretty complete; but as it is the nature of matter to be altered and worked upon by matter, so in a little time such a living creature must be destroyed, if there is no provision for repairing the injuries which she must commit on herself, and those to which she must be exposed from without. Therefore a treasure of blood is actually provided in the heart and vascular system, full of nutritious and healing particles, fluid enough to penetrate into the minutest parts of the animal; impelled by the heart, and conveyed by the arteries, it pervades every part, builds up what was broken down, and sweeps away the old and useless materials. Hence we see the necessity or advantage of the heart and arterial system. The heart consists of four cavities, from one of which, the blood is driven into the arteries through the body, by another, it is received back again by the veins : it then passes into the third, whence it is forced into the lungs. Having there been revivified by coming in contact with the air, it is carried back by a set of veins into the fourth cavity, and thence into that in which it began its course it is then again forced into the arteries, brought back by the veins, and thus circulates till the end of life. Each cavity of the heart is generally called into action four thousand times every hour. The arteries, into which the blood is forced, branch in every direction through the body, like the roots, branches, and leaves of a tree, running through the substance of the bones, and every part of the animal, till they are lost in such fine tubes as to be wholly invisible. In this man

STRUCTURE OF THE HUMAN BODY.

261

ner, they distribute nourishment, supply perspiration, and renew all the waste of the system; and by passing through glands in every part of the body, all the various animal secretions are elaborated. In the parts where the arteries are lost to the sight, the veins take their rise, and in their commencement are also imperceptible. The blood is then of a dark colour. In this discoloured state it has lost some of its vital power; but on being driven through the lungs its colour is restored. All this provision, however, would not be sufficient, for the store of blood would soon be consumed, and the fabric would break down, if there was not a provision for fresh supplies. And we actually find that on its passage from the lungs to the heart the blood receives a supply of a new fluid extracted from the food by myriads of fine tubes which carry it to a larger one, that empties itself into a large vein, and being mixed with the blood is conveyed to the heart. We see, therefore, by the very imperfect survey which we have been able to take of this subject, that the animal man must necessarily be complex in his corporeal system, and in its operations. He must have one great and general system, the vascular, branching through the whole circulation; another, the nervous, with its appendages the organs of sense, for every kind of feeling; and a third for the connexion and union of all these parts. Besides these primary and general systems, he requires others which may be more local or confined. One for strength, support, and protection; another for the requisite motion of the parts among themselves, as well as for moving from place to place, the muscular system; another to prepare nourishment for the daily recruit of the body, the digestive organs; and others for the various purposes of existence.

QUESTIONS.-1. What are the uses of the blood? 2. Describe the circulation of the blood. 3. Describe the arteries. 4. What changes does the blood undergo in the course of its circulation? 5. How is provision made for a fresh supply of blood? [NOTE. That cavity of the heart from which the blood is driven into the arteries is called the left ventricle; the next is called the right auricie; the third the right ventricle; and the fourth the left auricle.]

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